Update to MediaWiki 1.24.1

23 files changed, 3849 insertions, 2277 deletions

diff --git a/includes/db/ChronologyProtector.php b/includes/db/ChronologyProtector.php
index de5e72c3..0c7b612e 100644
--- a/includes/db/ChronologyProtector.php
+++ b/includes/db/ChronologyProtector.php
@@ -26,12 +26,14 @@
  * Kind of like Hawking's [[Chronology Protection Agency]].
  */
 class ChronologyProtector {
-	/** @var Array (DB master name => position) */
+	/** @var array (DB master name => position) */
 	protected $startupPositions = array();
-	/** @var Array (DB master name => position) */
+
+	/** @var array (DB master name => position) */
 	protected $shutdownPositions = array();
 
-	protected $initialized = false; // bool; whether the session data was loaded
+	/** @var bool Whether the session data was loaded */
+	protected $initialized = false;
 
 	/**
 	 * Initialise a LoadBalancer to give it appropriate chronology protection.
@@ -41,7 +43,7 @@ class ChronologyProtector {
 	 * to that position by delaying execution. The delay may timeout and allow stale
 	 * data if no non-lagged slaves are available.
 	 *
-	 * @param $lb LoadBalancer
+	 * @param LoadBalancer $lb
 	 * @return void
 	 */
 	public function initLB( LoadBalancer $lb ) {
@@ -67,7 +69,7 @@ class ChronologyProtector {
 	 * Notify the ChronologyProtector that the LoadBalancer is about to shut
 	 * down. Saves replication positions.
 	 *
-	 * @param $lb LoadBalancer
+	 * @param LoadBalancer $lb
 	 * @return void
 	 */
 	public function shutdownLB( LoadBalancer $lb ) {
@@ -83,6 +85,7 @@ class ChronologyProtector {
 		$info = $lb->parentInfo();
 		if ( !$db || !$db->doneWrites() ) {
 			wfDebug( __METHOD__ . ": LB {$info['id']}, no writes done\n" );
+
 			return;
 		}
 		$pos = $db->getMasterPos();
diff --git a/includes/db/CloneDatabase.php b/includes/db/CloneDatabase.php
index 819925cb..9eb3e2fa 100644
--- a/includes/db/CloneDatabase.php
+++ b/includes/db/CloneDatabase.php
@@ -3,7 +3,7 @@
  * Helper class for making a copy of the database, mostly for unit testing.
  *
  * Copyright © 2010 Chad Horohoe <chad@anyonecanedit.org>
- * http://www.mediawiki.org/
+ * https://www.mediawiki.org/
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -25,49 +25,33 @@
  */
 
 class CloneDatabase {
-
-	/**
-	 * Table prefix for cloning
-	 * @var String
-	 */
+	/** @var string Table prefix for cloning */
 	private $newTablePrefix = '';
 
-	/**
-	 * Current table prefix
-	 * @var String
-	 */
+	/** @var string Current table prefix */
 	private $oldTablePrefix = '';
 
-	/**
-	 * List of tables to be cloned
-	 * @var Array
-	 */
+	/** @var array List of tables to be cloned */
 	private $tablesToClone = array();
 
-	/**
-	 * Should we DROP tables containing the new names?
-	 * @var Bool
-	 */
+	/** @var bool Should we DROP tables containing the new names? */
 	private $dropCurrentTables = true;
 
-	/**
-	 * Whether to use temporary tables or not
-	 * @var Bool
-	 */
+	/** @var bool Whether to use temporary tables or not */
 	private $useTemporaryTables = true;
 
 	/**
 	 * Constructor
 	 *
-	 * @param $db DatabaseBase A database subclass
+	 * @param DatabaseBase $db A database subclass
 	 * @param array $tablesToClone An array of tables to clone, unprefixed
 	 * @param string $newTablePrefix Prefix to assign to the tables
 	 * @param string $oldTablePrefix Prefix on current tables, if not $wgDBprefix
-	 * @param $dropCurrentTables bool
+	 * @param bool $dropCurrentTables
 	 */
 	public function __construct( DatabaseBase $db, array $tablesToClone,
-		$newTablePrefix, $oldTablePrefix = '', $dropCurrentTables = true )
-	{
+		$newTablePrefix, $oldTablePrefix = '', $dropCurrentTables = true
+	) {
 		$this->db = $db;
 		$this->tablesToClone = $tablesToClone;
 		$this->newTablePrefix = $newTablePrefix;
@@ -87,7 +71,13 @@ class CloneDatabase {
 	 * Clone the table structure
 	 */
 	public function cloneTableStructure() {
+		global $wgSharedTables, $wgSharedDB;
 		foreach ( $this->tablesToClone as $tbl ) {
+			if ( $wgSharedDB && in_array( $tbl, $wgSharedTables, true ) ) {
+				// Shared tables don't work properly when cloning due to
+				// how prefixes are handled (bug 65654)
+				throw new MWException( "Cannot clone shared table $tbl." );
+			}
 			# Clean up from previous aborted run.  So that table escaping
 			# works correctly across DB engines, we need to change the pre-
 			# fix back and forth so tableName() works right.
@@ -98,14 +88,21 @@ class CloneDatabase {
 			self::changePrefix( $this->newTablePrefix );
 			$newTableName = $this->db->tableName( $tbl, 'raw' );
 
-			if ( $this->dropCurrentTables && !in_array( $this->db->getType(), array( 'postgres', 'oracle' ) ) ) {
+			if ( $this->dropCurrentTables
+				&& !in_array( $this->db->getType(), array( 'postgres', 'oracle' ) )
+			) {
+				if ( $oldTableName === $newTableName ) {
+					// Last ditch check to avoid data loss
+					throw new MWException( "Not dropping new table, as '$newTableName'"
+						. " is name of both the old and the new table." );
+				}
 				$this->db->dropTable( $tbl, __METHOD__ );
-				wfDebug( __METHOD__ . " dropping {$newTableName}\n", true );
+				wfDebug( __METHOD__ . " dropping {$newTableName}\n" );
 				//Dropping the oldTable because the prefix was changed
 			}
 
 			# Create new table
-			wfDebug( __METHOD__ . " duplicating $oldTableName to $newTableName\n", true );
+			wfDebug( __METHOD__ . " duplicating $oldTableName to $newTableName\n" );
 			$this->db->duplicateTableStructure( $oldTableName, $newTableName, $this->useTemporaryTables );
 		}
 	}
@@ -127,7 +124,7 @@ class CloneDatabase {
 	/**
 	 * Change the table prefix on all open DB connections/
 	 *
-	 * @param $prefix
+	 * @param string $prefix
 	 * @return void
 	 */
 	public static function changePrefix( $prefix ) {
@@ -137,8 +134,8 @@ class CloneDatabase {
 	}
 
 	/**
-	 * @param $lb LoadBalancer
-	 * @param $prefix
+	 * @param LoadBalancer $lb
+	 * @param string $prefix
 	 * @return void
 	 */
 	public static function changeLBPrefix( $lb, $prefix ) {
@@ -146,8 +143,8 @@ class CloneDatabase {
 	}
 
 	/**
-	 * @param $db DatabaseBase
-	 * @param $prefix
+	 * @param DatabaseBase $db
+	 * @param string $prefix
 	 * @return void
 	 */
 	public static function changeDBPrefix( $db, $prefix ) {
diff --git a/includes/db/Database.php b/includes/db/Database.php
index 10645608..9b783a99 100644
--- a/includes/db/Database.php
+++ b/includes/db/Database.php
@@ -1,4 +1,5 @@
 <?php
+
 /**
  * @defgroup Database Database
  *
@@ -42,10 +43,10 @@ interface DatabaseType {
 	/**
 	 * Open a connection to the database. Usually aborts on failure
 	 *
-	 * @param string $server database server host
-	 * @param string $user database user name
-	 * @param string $password database user password
-	 * @param string $dbName database name
+	 * @param string $server Database server host
+	 * @param string $user Database user name
+	 * @param string $password Database user password
+	 * @param string $dbName Database name
 	 * @return bool
 	 * @throws DBConnectionError
 	 */
@@ -57,18 +58,18 @@ interface DatabaseType {
 	 * member variables.
 	 * If no more rows are available, false is returned.
 	 *
-	 * @param $res ResultWrapper|object as returned from DatabaseBase::query(), etc.
-	 * @return object|bool
+	 * @param ResultWrapper|stdClass $res Object as returned from DatabaseBase::query(), etc.
+	 * @return stdClass|bool
 	 * @throws DBUnexpectedError Thrown if the database returns an error
 	 */
 	function fetchObject( $res );
 
 	/**
 	 * Fetch the next row from the given result object, in associative array
-	 * form.  Fields are retrieved with $row['fieldname'].
+	 * form. Fields are retrieved with $row['fieldname'].
 	 * If no more rows are available, false is returned.
 	 *
-	 * @param $res ResultWrapper result object as returned from DatabaseBase::query(), etc.
+	 * @param ResultWrapper $res Result object as returned from DatabaseBase::query(), etc.
 	 * @return array|bool
 	 * @throws DBUnexpectedError Thrown if the database returns an error
 	 */
@@ -77,7 +78,7 @@ interface DatabaseType {
 	/**
 	 * Get the number of rows in a result object
 	 *
-	 * @param $res Mixed: A SQL result
+	 * @param mixed $res A SQL result
 	 * @return int
 	 */
 	function numRows( $res );
@@ -86,7 +87,7 @@ interface DatabaseType {
 	 * Get the number of fields in a result object
 	 * @see http://www.php.net/mysql_num_fields
 	 *
-	 * @param $res Mixed: A SQL result
+	 * @param mixed $res A SQL result
 	 * @return int
 	 */
 	function numFields( $res );
@@ -95,8 +96,8 @@ interface DatabaseType {
 	 * Get a field name in a result object
 	 * @see http://www.php.net/mysql_field_name
 	 *
-	 * @param $res Mixed: A SQL result
-	 * @param $n Integer
+	 * @param mixed $res A SQL result
+	 * @param int $n
 	 * @return string
 	 */
 	function fieldName( $res, $n );
@@ -119,8 +120,8 @@ interface DatabaseType {
 	 * Change the position of the cursor in a result object
 	 * @see http://www.php.net/mysql_data_seek
 	 *
-	 * @param $res Mixed: A SQL result
-	 * @param $row Mixed: Either MySQL row or ResultWrapper
+	 * @param mixed $res A SQL result
+	 * @param int $row
 	 */
 	function dataSeek( $res, $row );
 
@@ -144,8 +145,8 @@ interface DatabaseType {
 	 * mysql_fetch_field() wrapper
 	 * Returns false if the field doesn't exist
 	 *
-	 * @param string $table table name
-	 * @param string $field field name
+	 * @param string $table Table name
+	 * @param string $field Field name
 	 *
 	 * @return Field
 	 */
@@ -156,7 +157,7 @@ interface DatabaseType {
 	 * @param string $table Table name
 	 * @param string $index Index name
 	 * @param string $fname Calling function name
-	 * @return Mixed: Database-specific index description class or false if the index does not exist
+	 * @return mixed Database-specific index description class or false if the index does not exist
 	 */
 	function indexInfo( $table, $index, $fname = __METHOD__ );
 
@@ -171,18 +172,18 @@ interface DatabaseType {
 	/**
 	 * Wrapper for addslashes()
 	 *
-	 * @param string $s to be slashed.
-	 * @return string: slashed string.
+	 * @param string $s String to be slashed.
+	 * @return string Slashed string.
 	 */
 	function strencode( $s );
 
 	/**
 	 * Returns a wikitext link to the DB's website, e.g.,
-	 *     return "[http://www.mysql.com/ MySQL]";
+	 *   return "[http://www.mysql.com/ MySQL]";
 	 * Should at least contain plain text, if for some reason
 	 * your database has no website.
 	 *
-	 * @return string: wikitext of a link to the server software's web site
+	 * @return string Wikitext of a link to the server software's web site
 	 */
 	function getSoftwareLink();
 
@@ -190,16 +191,16 @@ interface DatabaseType {
 	 * A string describing the current software version, like from
 	 * mysql_get_server_info().
 	 *
-	 * @return string: Version information from the database server.
+	 * @return string Version information from the database server.
 	 */
 	function getServerVersion();
 
 	/**
 	 * A string describing the current software version, and possibly
-	 * other details in a user-friendly way.  Will be listed on Special:Version, etc.
+	 * other details in a user-friendly way. Will be listed on Special:Version, etc.
 	 * Use getServerVersion() to get machine-friendly information.
 	 *
-	 * @return string: Version information from the database server
+	 * @return string Version information from the database server
 	 */
 	function getServerInfo();
 }
@@ -208,7 +209,8 @@ interface DatabaseType {
  * Interface for classes that implement or wrap DatabaseBase
  * @ingroup Database
  */
-interface IDatabase {}
+interface IDatabase {
+}
 
 /**
  * Database abstraction object
@@ -217,8 +219,10 @@ interface IDatabase {}
 abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/** Number of times to re-try an operation in case of deadlock */
 	const DEADLOCK_TRIES = 4;
+
 	/** Minimum time to wait before retry, in microseconds */
 	const DEADLOCK_DELAY_MIN = 500000;
+
 	/** Maximum time to wait before retry */
 	const DEADLOCK_DELAY_MAX = 1500000;
 
@@ -232,6 +236,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	protected $mServer, $mUser, $mPassword, $mDBname;
 
+	/** @var resource Database connection */
 	protected $mConn = null;
 	protected $mOpened = false;
 
@@ -241,12 +246,11 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	protected $mTrxPreCommitCallbacks = array();
 
 	protected $mTablePrefix;
+	protected $mSchema;
 	protected $mFlags;
 	protected $mForeign;
-	protected $mTrxLevel = 0;
 	protected $mErrorCount = 0;
 	protected $mLBInfo = array();
-	protected $mFakeSlaveLag = null, $mFakeMaster = false;
 	protected $mDefaultBigSelects = null;
 	protected $mSchemaVars = false;
 
@@ -257,10 +261,25 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	protected $delimiter = ';';
 
 	/**
+	 * Either 1 if a transaction is active or 0 otherwise.
+	 * The other Trx fields may not be meaningfull if this is 0.
+	 *
+	 * @var int
+	 */
+	protected $mTrxLevel = 0;
+
+	/**
+	 * Either a short hexidecimal string if a transaction is active or ""
+	 *
+	 * @var string
+	 */
+	protected $mTrxShortId = '';
+
+	/**
 	 * Remembers the function name given for starting the most recent transaction via begin().
 	 * Used to provide additional context for error reporting.
 	 *
-	 * @var String
+	 * @var string
 	 * @see DatabaseBase::mTrxLevel
 	 */
 	private $mTrxFname = null;
@@ -268,7 +287,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Record if possible write queries were done in the last transaction started
 	 *
-	 * @var Bool
+	 * @var bool
 	 * @see DatabaseBase::mTrxLevel
 	 */
 	private $mTrxDoneWrites = false;
@@ -276,20 +295,34 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Record if the current transaction was started implicitly due to DBO_TRX being set.
 	 *
-	 * @var Bool
+	 * @var bool
 	 * @see DatabaseBase::mTrxLevel
 	 */
 	private $mTrxAutomatic = false;
 
 	/**
+	 * Array of levels of atomicity within transactions
+	 *
+	 * @var SplStack
+	 */
+	private $mTrxAtomicLevels;
+
+	/**
+	 * Record if the current transaction was started implicitly by DatabaseBase::startAtomic
+	 *
+	 * @var bool
+	 */
+	private $mTrxAutomaticAtomic = false;
+
+	/**
 	 * @since 1.21
-	 * @var file handle for upgrade
+	 * @var resource File handle for upgrade
 	 */
 	protected $fileHandle = null;
 
 	/**
 	 * @since 1.22
-	 * @var Process cache of VIEWs names in the database
+	 * @var string[] Process cache of VIEWs names in the database
 	 */
 	protected $allViews = null;
 
@@ -300,17 +333,17 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * A string describing the current software version, and possibly
-	 * other details in a user-friendly way.  Will be listed on Special:Version, etc.
+	 * other details in a user-friendly way. Will be listed on Special:Version, etc.
 	 * Use getServerVersion() to get machine-friendly information.
 	 *
-	 * @return string: Version information from the database server
+	 * @return string Version information from the database server
 	 */
 	public function getServerInfo() {
 		return $this->getServerVersion();
 	}
 
 	/**
-	 * @return string: command delimiter used by this database engine
+	 * @return string Command delimiter used by this database engine
 	 */
 	public function getDelimiter() {
 		return $this->delimiter;
@@ -318,12 +351,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Boolean, controls output of large amounts of debug information.
-	 * @param $debug bool|null
+	 * @param bool|null $debug
 	 *   - true to enable debugging
 	 *   - false to disable debugging
 	 *   - omitted or null to do nothing
 	 *
-	 * @return bool|null previous value of the flag
+	 * @return bool|null Previous value of the flag
 	 */
 	public function debug( $debug = null ) {
 		return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
@@ -347,8 +380,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * split up queries into batches using a LIMIT clause than to switch off
 	 * buffering.
 	 *
-	 * @param $buffer null|bool
-	 *
+	 * @param null|bool $buffer
 	 * @return null|bool The previous value of the flag
 	 */
 	public function bufferResults( $buffer = null ) {
@@ -368,8 +400,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * Do not use this function outside of the Database classes.
 	 *
-	 * @param $ignoreErrors bool|null
-	 *
+	 * @param null|bool $ignoreErrors
 	 * @return bool The previous value of the flag.
 	 */
 	public function ignoreErrors( $ignoreErrors = null ) {
@@ -377,16 +408,15 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * Gets or sets the current transaction level.
+	 * Gets the current transaction level.
 	 *
 	 * Historically, transactions were allowed to be "nested". This is no
 	 * longer supported, so this function really only returns a boolean.
 	 *
-	 * @param int $level An integer (0 or 1), or omitted to leave it unchanged.
 	 * @return int The previous value
 	 */
-	public function trxLevel( $level = null ) {
-		return wfSetVar( $this->mTrxLevel, $level );
+	public function trxLevel() {
+		return $this->mTrxLevel;
 	}
 
 	/**
@@ -408,9 +438,18 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
+	 * Get/set the db schema.
+	 * @param string $schema The database schema to set, or omitted to leave it unchanged.
+	 * @return string The previous db schema.
+	 */
+	public function dbSchema( $schema = null ) {
+		return wfSetVar( $this->mSchema, $schema );
+	}
+
+	/**
 	 * Set the filehandle to copy write statements to.
 	 *
-	 * @param $fh filehandle
+	 * @param resource $fh File handle
 	 */
 	public function setFileHandle( $fh ) {
 		$this->fileHandle = $fh;
@@ -423,7 +462,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @param string $name The entry of the info array to get, or null to get the
 	 *   whole array
 	 *
-	 * @return LoadBalancer|null
+	 * @return array|mixed|null
 	 */
 	public function getLBInfo( $name = null ) {
 		if ( is_null( $name ) ) {
@@ -442,8 +481,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * the LB info array is set to that parameter. If it is called with two
 	 * parameters, the member with the given name is set to the given value.
 	 *
-	 * @param $name
-	 * @param $value
+	 * @param string $name
+	 * @param array $value
 	 */
 	public function setLBInfo( $name, $value = null ) {
 		if ( is_null( $value ) ) {
@@ -456,19 +495,19 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Set lag time in seconds for a fake slave
 	 *
-	 * @param $lag int
+	 * @param mixed $lag Valid values for this parameter are determined by the
+	 *   subclass, but should be a PHP scalar or array that would be sensible
+	 *   as part of $wgLBFactoryConf.
 	 */
 	public function setFakeSlaveLag( $lag ) {
-		$this->mFakeSlaveLag = $lag;
 	}
 
 	/**
 	 * Make this connection a fake master
 	 *
-	 * @param $enabled bool
+	 * @param bool $enabled
 	 */
 	public function setFakeMaster( $enabled = true ) {
-		$this->mFakeMaster = $enabled;
 	}
 
 	/**
@@ -548,7 +587,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Return the last query that went through DatabaseBase::query()
-	 * @return String
+	 * @return string
 	 */
 	public function lastQuery() {
 		return $this->mLastQuery;
@@ -561,7 +600,18 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @return bool
 	 */
 	public function doneWrites() {
-		return $this->mDoneWrites;
+		return (bool)$this->mDoneWrites;
+	}
+
+	/**
+	 * Returns the last time the connection may have been used for write queries.
+	 * Should return a timestamp if unsure.
+	 *
+	 * @return int|float UNIX timestamp or false
+	 * @since 1.24
+	 */
+	public function lastDoneWrites() {
+		return $this->mDoneWrites ?: false;
 	}
 
 	/**
@@ -578,7 +628,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Is a connection to the database open?
-	 * @return Boolean
+	 * @return bool
 	 */
 	public function isOpen() {
 		return $this->mOpened;
@@ -587,7 +637,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Set a flag for this connection
 	 *
-	 * @param $flag Integer: DBO_* constants from Defines.php:
+	 * @param int $flag DBO_* constants from Defines.php:
 	 *   - DBO_DEBUG: output some debug info (same as debug())
 	 *   - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
 	 *   - DBO_TRX: automatically start transactions
@@ -598,15 +648,21 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	public function setFlag( $flag ) {
 		global $wgDebugDBTransactions;
 		$this->mFlags |= $flag;
-		if ( ( $flag & DBO_TRX ) & $wgDebugDBTransactions ) {
-			wfDebug( "Implicit transactions are now  disabled.\n" );
+		if ( ( $flag & DBO_TRX ) && $wgDebugDBTransactions ) {
+			wfDebug( "Implicit transactions are now enabled.\n" );
 		}
 	}
 
 	/**
 	 * Clear a flag for this connection
 	 *
-	 * @param $flag: same as setFlag()'s $flag param
+	 * @param int $flag DBO_* constants from Defines.php:
+	 *   - DBO_DEBUG: output some debug info (same as debug())
+	 *   - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
+	 *   - DBO_TRX: automatically start transactions
+	 *   - DBO_DEFAULT: automatically sets DBO_TRX if not in command line mode
+	 *       and removes it in command line mode
+	 *   - DBO_PERSISTENT: use persistant database connection
 	 */
 	public function clearFlag( $flag ) {
 		global $wgDebugDBTransactions;
@@ -619,8 +675,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Returns a boolean whether the flag $flag is set for this connection
 	 *
-	 * @param $flag: same as setFlag()'s $flag param
-	 * @return Boolean
+	 * @param int $flag DBO_* constants from Defines.php:
+	 *   - DBO_DEBUG: output some debug info (same as debug())
+	 *   - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
+	 *   - DBO_TRX: automatically start transactions
+	 *   - DBO_PERSISTENT: use persistant database connection
+	 * @return bool
 	 */
 	public function getFlag( $flag ) {
 		return !!( $this->mFlags & $flag );
@@ -629,8 +689,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * General read-only accessor
 	 *
-	 * @param $name string
-	 *
+	 * @param string $name
 	 * @return string
 	 */
 	public function getProperty( $name ) {
@@ -649,19 +708,42 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * Return a path to the DBMS-specific schema file, otherwise default to tables.sql
+	 * Return a path to the DBMS-specific SQL file if it exists,
+	 * otherwise default SQL file
 	 *
+	 * @param string $filename
 	 * @return string
 	 */
-	public function getSchemaPath() {
+	private function getSqlFilePath( $filename ) {
 		global $IP;
-		if ( file_exists( "$IP/maintenance/" . $this->getType() . "/tables.sql" ) ) {
-			return "$IP/maintenance/" . $this->getType() . "/tables.sql";
+		$dbmsSpecificFilePath = "$IP/maintenance/" . $this->getType() . "/$filename";
+		if ( file_exists( $dbmsSpecificFilePath ) ) {
+			return $dbmsSpecificFilePath;
 		} else {
-			return "$IP/maintenance/tables.sql";
+			return "$IP/maintenance/$filename";
 		}
 	}
 
+	/**
+	 * Return a path to the DBMS-specific schema file,
+	 * otherwise default to tables.sql
+	 *
+	 * @return string
+	 */
+	public function getSchemaPath() {
+		return $this->getSqlFilePath( 'tables.sql' );
+	}
+
+	/**
+	 * Return a path to the DBMS-specific update key file,
+	 * otherwise default to update-keys.sql
+	 *
+	 * @return string
+	 */
+	public function getUpdateKeysPath() {
+		return $this->getSqlFilePath( 'update-keys.sql' );
+	}
+
 # ------------------------------------------------------------------------------
 # Other functions
 # ------------------------------------------------------------------------------
@@ -673,28 +755,39 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * connection object, by specifying no parameters to __construct(). This
 	 * feature is deprecated and should be removed.
 	 *
-	 * FIXME: The long list of formal parameters here is not really appropriate
-	 * for MySQL, and not at all appropriate for any other DBMS. It should be
-	 * replaced by named parameters as in DatabaseBase::factory().
-	 *
 	 * DatabaseBase subclasses should not be constructed directly in external
 	 * code. DatabaseBase::factory() should be used instead.
 	 *
-	 * @param string $server database server host
-	 * @param string $user database user name
-	 * @param string $password database user password
-	 * @param string $dbName database name
-	 * @param $flags
-	 * @param string $tablePrefix database table prefixes. By default use the prefix gave in LocalSettings.php
-	 * @param bool $foreign disable some operations specific to local databases
+	 * @param array $params Parameters passed from DatabaseBase::factory()
 	 */
-	function __construct( $server = false, $user = false, $password = false, $dbName = false,
-		$flags = 0, $tablePrefix = 'get from global', $foreign = false
-	) {
-		global $wgDBprefix, $wgCommandLineMode, $wgDebugDBTransactions;
+	function __construct( $params = null ) {
+		global $wgDBprefix, $wgDBmwschema, $wgCommandLineMode, $wgDebugDBTransactions;
 
-		$this->mFlags = $flags;
+		$this->mTrxAtomicLevels = new SplStack;
+
+		if ( is_array( $params ) ) { // MW 1.22
+			$server = $params['host'];
+			$user = $params['user'];
+			$password = $params['password'];
+			$dbName = $params['dbname'];
+			$flags = $params['flags'];
+			$tablePrefix = $params['tablePrefix'];
+			$schema = $params['schema'];
+			$foreign = $params['foreign'];
+		} else { // legacy calling pattern
+			wfDeprecated( __METHOD__ . " method called without parameter array.", "1.23" );
+			$args = func_get_args();
+			$server = isset( $args[0] ) ? $args[0] : false;
+			$user = isset( $args[1] ) ? $args[1] : false;
+			$password = isset( $args[2] ) ? $args[2] : false;
+			$dbName = isset( $args[3] ) ? $args[3] : false;
+			$flags = isset( $args[4] ) ? $args[4] : 0;
+			$tablePrefix = isset( $args[5] ) ? $args[5] : 'get from global';
+			$schema = 'get from global';
+			$foreign = isset( $args[6] ) ? $args[6] : false;
+		}
 
+		$this->mFlags = $flags;
 		if ( $this->mFlags & DBO_DEFAULT ) {
 			if ( $wgCommandLineMode ) {
 				$this->mFlags &= ~DBO_TRX;
@@ -716,6 +809,13 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			$this->mTablePrefix = $tablePrefix;
 		}
 
+		/** Get the database schema*/
+		if ( $schema == 'get from global' ) {
+			$this->mSchema = $wgDBmwschema;
+		} else {
+			$this->mSchema = $schema;
+		}
+
 		$this->mForeign = $foreign;
 
 		if ( $user ) {
@@ -729,13 +829,14 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * not restored on unserialize.
 	 */
 	public function __sleep() {
-		throw new MWException( 'Database serialization may cause problems, since the connection is not restored on wakeup.' );
+		throw new MWException( 'Database serialization may cause problems, since ' .
+			'the connection is not restored on wakeup.' );
 	}
 
 	/**
 	 * Given a DB type, construct the name of the appropriate child class of
 	 * DatabaseBase. This is designed to replace all of the manual stuff like:
-	 *	$class = 'Database' . ucfirst( strtolower( $dbType ) );
+	 *    $class = 'Database' . ucfirst( strtolower( $dbType ) );
 	 * as well as validate against the canonical list of DB types we have
 	 *
 	 * This factory function is mostly useful for when you need to connect to a
@@ -744,22 +845,23 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * database. Example uses in core:
 	 * @see LoadBalancer::reallyOpenConnection()
 	 * @see ForeignDBRepo::getMasterDB()
-	 * @see WebInstaller_DBConnect::execute()
+	 * @see WebInstallerDBConnect::execute()
 	 *
 	 * @since 1.18
 	 *
 	 * @param string $dbType A possible DB type
 	 * @param array $p An array of options to pass to the constructor.
-	 *    Valid options are: host, user, password, dbname, flags, tablePrefix, driver
-	 * @return DatabaseBase subclass or null
+	 *    Valid options are: host, user, password, dbname, flags, tablePrefix, schema, driver
+	 * @throws MWException If the database driver or extension cannot be found
+	 * @return DatabaseBase|null DatabaseBase subclass or null
 	 */
 	final public static function factory( $dbType, $p = array() ) {
 		$canonicalDBTypes = array(
-			'mysql'    => array( 'mysqli', 'mysql' ),
+			'mysql' => array( 'mysqli', 'mysql' ),
 			'postgres' => array(),
-			'sqlite'   => array(),
-			'oracle'   => array(),
-			'mssql'    => array(),
+			'sqlite' => array(),
+			'oracle' => array(),
+			'mssql' => array(),
 		);
 
 		$driver = false;
@@ -789,17 +891,32 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				" no viable database extension found for type '$dbType'" );
 		}
 
+		// Determine schema defaults. Currently Microsoft SQL Server uses $wgDBmwschema,
+		// and everything else doesn't use a schema (e.g. null)
+		// Although postgres and oracle support schemas, we don't use them (yet)
+		// to maintain backwards compatibility
+		$defaultSchemas = array(
+			'mysql' => null,
+			'postgres' => null,
+			'sqlite' => null,
+			'oracle' => null,
+			'mssql' => 'get from global',
+		);
+
 		$class = 'Database' . ucfirst( $driver );
 		if ( class_exists( $class ) && is_subclass_of( $class, 'DatabaseBase' ) ) {
-			return new $class(
-				isset( $p['host'] ) ? $p['host'] : false,
-				isset( $p['user'] ) ? $p['user'] : false,
-				isset( $p['password'] ) ? $p['password'] : false,
-				isset( $p['dbname'] ) ? $p['dbname'] : false,
-				isset( $p['flags'] ) ? $p['flags'] : 0,
-				isset( $p['tablePrefix'] ) ? $p['tablePrefix'] : 'get from global',
-				isset( $p['foreign'] ) ? $p['foreign'] : false
+			$params = array(
+				'host' => isset( $p['host'] ) ? $p['host'] : false,
+				'user' => isset( $p['user'] ) ? $p['user'] : false,
+				'password' => isset( $p['password'] ) ? $p['password'] : false,
+				'dbname' => isset( $p['dbname'] ) ? $p['dbname'] : false,
+				'flags' => isset( $p['flags'] ) ? $p['flags'] : 0,
+				'tablePrefix' => isset( $p['tablePrefix'] ) ? $p['tablePrefix'] : 'get from global',
+				'schema' => isset( $p['schema'] ) ? $p['schema'] : $defaultSchemas[$dbType],
+				'foreign' => isset( $p['foreign'] ) ? $p['foreign'] : false
 			);
+
+			return new $class( $params );
 		} else {
 			return null;
 		}
@@ -822,6 +939,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		if ( $this->mPHPError ) {
 			$error = preg_replace( '!\[<a.*</a>\]!', '', $this->mPHPError );
 			$error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
+
 			return $error;
 		} else {
 			return false;
@@ -829,9 +947,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * @param $errno
-	 * @param $errstr
-	 * @access private
+	 * @param int $errno
+	 * @param string $errstr
 	 */
 	public function connectionErrorHandler( $errno, $errstr ) {
 		$this->mPHPError = $errstr;
@@ -842,13 +959,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * if it is open : commits any open transactions
 	 *
 	 * @throws MWException
-	 * @return Bool operation success. true if already closed.
+	 * @return bool Operation success. true if already closed.
 	 */
 	public function close() {
 		if ( count( $this->mTrxIdleCallbacks ) ) { // sanity
 			throw new MWException( "Transaction idle callbacks still pending." );
 		}
-		$this->mOpened = false;
 		if ( $this->mConn ) {
 			if ( $this->trxLevel() ) {
 				if ( !$this->mTrxAutomatic ) {
@@ -859,23 +975,25 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				$this->commit( __METHOD__, 'flush' );
 			}
 
-			$ret = $this->closeConnection();
+			$closed = $this->closeConnection();
 			$this->mConn = false;
-			return $ret;
 		} else {
-			return true;
+			$closed = true;
 		}
+		$this->mOpened = false;
+
+		return $closed;
 	}
 
 	/**
 	 * Closes underlying database connection
 	 * @since 1.20
-	 * @return bool: Whether connection was closed successfully
+	 * @return bool Whether connection was closed successfully
 	 */
 	abstract protected function closeConnection();
 
 	/**
-	 * @param string $error fallback error message, used if none is given by DB
+	 * @param string $error Fallback error message, used if none is given by DB
 	 * @throws DBConnectionError
 	 */
 	function reportConnectionError( $error = 'Unknown error' ) {
@@ -891,8 +1009,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * The DBMS-dependent part of query()
 	 *
-	 * @param  $sql String: SQL query.
-	 * @return ResultWrapper Result object to feed to fetchObject, fetchRow, ...; or false on failure
+	 * @param string $sql SQL query.
+	 * @return ResultWrapper|bool Result object to feed to fetchObject,
+	 *   fetchRow, ...; or false on failure
 	 */
 	abstract protected function doQuery( $sql );
 
@@ -900,8 +1019,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Determine whether a query writes to the DB.
 	 * Should return true if unsure.
 	 *
-	 * @param $sql string
-	 *
+	 * @param string $sql
 	 * @return bool
 	 */
 	public function isWriteQuery( $sql ) {
@@ -921,23 +1039,23 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * However, the query wrappers themselves should call this function.
 	 *
-	 * @param  $sql        String: SQL query
-	 * @param  $fname      String: Name of the calling function, for profiling/SHOW PROCESSLIST
+	 * @param string $sql SQL query
+	 * @param string $fname Name of the calling function, for profiling/SHOW PROCESSLIST
 	 *     comment (you can use __METHOD__ or add some extra info)
-	 * @param  $tempIgnore Boolean:   Whether to avoid throwing an exception on errors...
+	 * @param bool $tempIgnore Whether to avoid throwing an exception on errors...
 	 *     maybe best to catch the exception instead?
 	 * @throws MWException
-	 * @return boolean|ResultWrapper. true for a successful write query, ResultWrapper object
+	 * @return bool|ResultWrapper True for a successful write query, ResultWrapper object
 	 *     for a successful read query, or false on failure if $tempIgnore set
 	 */
 	public function query( $sql, $fname = __METHOD__, $tempIgnore = false ) {
-		global $wgUser, $wgDebugDBTransactions;
+		global $wgUser, $wgDebugDBTransactions, $wgDebugDumpSqlLength;
 
 		$this->mLastQuery = $sql;
-		if ( !$this->mDoneWrites && $this->isWriteQuery( $sql ) ) {
+		if ( $this->isWriteQuery( $sql ) ) {
 			# Set a flag indicating that writes have been done
-			wfDebug( __METHOD__ . ": Writes done: $sql\n" );
-			$this->mDoneWrites = true;
+			wfDebug( __METHOD__ . ': Writes done: ' . DatabaseBase::generalizeSQL( $sql ) . "\n" );
+			$this->mDoneWrites = microtime( true );
 		}
 
 		# Add a comment for easy SHOW PROCESSLIST interpretation
@@ -957,8 +1075,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 		# If DBO_TRX is set, start a transaction
 		if ( ( $this->mFlags & DBO_TRX ) && !$this->mTrxLevel &&
-			$sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK' )
-		{
+			$sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK'
+		) {
 			# Avoid establishing transactions for SHOW and SET statements too -
 			# that would delay transaction initializations to once connection
 			# is really used by application
@@ -975,10 +1093,14 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		# Keep track of whether the transaction has write queries pending
 		if ( $this->mTrxLevel && !$this->mTrxDoneWrites && $this->isWriteQuery( $sql ) ) {
 			$this->mTrxDoneWrites = true;
-			Profiler::instance()->transactionWritingIn( $this->mServer, $this->mDBname );
+			Profiler::instance()->transactionWritingIn(
+				$this->mServer, $this->mDBname, $this->mTrxShortId );
 		}
 
+		$queryProf = '';
+		$totalProf = '';
 		$isMaster = !is_null( $this->getLBInfo( 'master' ) );
+
 		if ( !Profiler::instance()->isStub() ) {
 			# generalizeSQL will probably cut down the query to reasonable
 			# logging size most of the time. The substr is really just a sanity check.
@@ -989,6 +1111,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				$queryProf = 'query: ' . substr( DatabaseBase::generalizeSQL( $sql ), 0, 255 );
 				$totalProf = 'DatabaseBase::query';
 			}
+			# Include query transaction state
+			$queryProf .= $this->mTrxShortId ? " [TRX#{$this->mTrxShortId}]" : "";
+
+			$trx = $this->mTrxLevel ? 'TRX=yes' : 'TRX=no';
 			wfProfileIn( $totalProf );
 			wfProfileIn( $queryProf );
 		}
@@ -997,7 +1123,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			static $cnt = 0;
 
 			$cnt++;
-			$sqlx = substr( $commentedSql, 0, 500 );
+			$sqlx = $wgDebugDumpSqlLength ? substr( $commentedSql, 0, $wgDebugDumpSqlLength )
+				: $commentedSql;
 			$sqlx = strtr( $sqlx, "\t\n", '  ' );
 
 			$master = $isMaster ? 'master' : 'slave';
@@ -1006,6 +1133,11 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 		$queryId = MWDebug::query( $sql, $fname, $isMaster );
 
+		# Avoid fatals if close() was called
+		if ( !$this->isOpen() ) {
+			throw new DBUnexpectedError( $this, "DB connection was already closed." );
+		}
+
 		# Do the query and handle errors
 		$ret = $this->doQuery( $commentedSql );
 
@@ -1014,22 +1146,33 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		# Try reconnecting if the connection was lost
 		if ( false === $ret && $this->wasErrorReissuable() ) {
 			# Transaction is gone, like it or not
+			$hadTrx = $this->mTrxLevel; // possible lost transaction
 			$this->mTrxLevel = 0;
-			$this->mTrxIdleCallbacks = array(); // cancel
-			$this->mTrxPreCommitCallbacks = array(); // cancel
+			$this->mTrxIdleCallbacks = array(); // bug 65263
+			$this->mTrxPreCommitCallbacks = array(); // bug 65263
 			wfDebug( "Connection lost, reconnecting...\n" );
-
+			# Stash the last error values since ping() might clear them
+			$lastError = $this->lastError();
+			$lastErrno = $this->lastErrno();
 			if ( $this->ping() ) {
+				global $wgRequestTime;
 				wfDebug( "Reconnected\n" );
-				$sqlx = substr( $commentedSql, 0, 500 );
+				$sqlx = $wgDebugDumpSqlLength ? substr( $commentedSql, 0, $wgDebugDumpSqlLength )
+					: $commentedSql;
 				$sqlx = strtr( $sqlx, "\t\n", '  ' );
-				global $wgRequestTime;
 				$elapsed = round( microtime( true ) - $wgRequestTime, 3 );
 				if ( $elapsed < 300 ) {
 					# Not a database error to lose a transaction after a minute or two
-					wfLogDBError( "Connection lost and reconnected after {$elapsed}s, query: $sqlx\n" );
+					wfLogDBError( "Connection lost and reconnected after {$elapsed}s, query: $sqlx" );
+				}
+				if ( $hadTrx ) {
+					# Leave $ret as false and let an error be reported.
+					# Callers may catch the exception and continue to use the DB.
+					$this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $tempIgnore );
+				} else {
+					# Should be safe to silently retry (no trx and thus no callbacks)
+					$ret = $this->doQuery( $commentedSql );
 				}
-				$ret = $this->doQuery( $commentedSql );
 			} else {
 				wfDebug( "Failed\n" );
 			}
@@ -1051,11 +1194,11 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Report a query error. Log the error, and if neither the object ignore
 	 * flag nor the $tempIgnore flag is set, throw a DBQueryError.
 	 *
-	 * @param $error String
-	 * @param $errno Integer
-	 * @param $sql String
-	 * @param $fname String
-	 * @param $tempIgnore Boolean
+	 * @param string $error
+	 * @param int $errno
+	 * @param string $sql
+	 * @param string $fname
+	 * @param bool $tempIgnore
 	 * @throws DBQueryError
 	 */
 	public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
@@ -1067,8 +1210,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			wfDebug( "SQL ERROR (ignored): $error\n" );
 			$this->ignoreErrors( $ignore );
 		} else {
-			$sql1line = str_replace( "\n", "\\n", $sql );
-			wfLogDBError( "$fname\t{$this->mServer}\t$errno\t$error\t$sql1line\n" );
+			$sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
+			wfLogDBError( "$fname\t{$this->mServer}\t$errno\t$error\t$sql1line" );
 			wfDebug( "SQL ERROR: " . $error . "\n" );
 			throw new DBQueryError( $this, $error, $errno, $sql, $fname );
 		}
@@ -1083,21 +1226,22 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * & = filename; reads the file and inserts as a blob
 	 *     (we don't use this though...)
 	 *
-	 * @param $sql string
-	 * @param $func string
+	 * @param string $sql
+	 * @param string $func
 	 *
 	 * @return array
 	 */
 	protected function prepare( $sql, $func = 'DatabaseBase::prepare' ) {
 		/* MySQL doesn't support prepared statements (yet), so just
-		   pack up the query for reference. We'll manually replace
-		   the bits later. */
+		 * pack up the query for reference. We'll manually replace
+		 * the bits later.
+		 */
 		return array( 'query' => $sql, 'func' => $func );
 	}
 
 	/**
 	 * Free a prepared query, generated by prepare().
-	 * @param $prepared
+	 * @param string $prepared
 	 */
 	protected function freePrepared( $prepared ) {
 		/* No-op by default */
@@ -1105,8 +1249,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Execute a prepared query with the various arguments
-	 * @param string $prepared the prepared sql
-	 * @param $args Mixed: Either an array here, or put scalars as varargs
+	 * @param string $prepared The prepared sql
+	 * @param mixed $args Either an array here, or put scalars as varargs
 	 *
 	 * @return ResultWrapper
 	 */
@@ -1125,9 +1269,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * For faking prepared SQL statements on DBs that don't support it directly.
 	 *
-	 * @param string $preparedQuery a 'preparable' SQL statement
-	 * @param array $args of arguments to fill it with
-	 * @return string executable SQL
+	 * @param string $preparedQuery A 'preparable' SQL statement
+	 * @param array $args Array of Arguments to fill it with
+	 * @return string Executable SQL
 	 */
 	public function fillPrepared( $preparedQuery, $args ) {
 		reset( $args );
@@ -1142,9 +1286,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * The arguments should be in $this->preparedArgs and must not be touched
 	 * while we're doing this.
 	 *
-	 * @param $matches Array
+	 * @param array $matches
 	 * @throws DBUnexpectedError
-	 * @return String
+	 * @return string
 	 */
 	protected function fillPreparedArg( $matches ) {
 		switch ( $matches[1] ) {
@@ -1165,9 +1309,15 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				return $arg;
 			case '&':
 				# return $this->addQuotes( file_get_contents( $arg ) );
-				throw new DBUnexpectedError( $this, '& mode is not implemented. If it\'s really needed, uncomment the line above.' );
+				throw new DBUnexpectedError(
+					$this,
+					'& mode is not implemented. If it\'s really needed, uncomment the line above.'
+				);
 			default:
-				throw new DBUnexpectedError( $this, 'Received invalid match. This should never happen!' );
+				throw new DBUnexpectedError(
+					$this,
+					'Received invalid match. This should never happen!'
+				);
 		}
 	}
 
@@ -1176,7 +1326,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * necessary to call this, just use unset() or let the variable holding
 	 * the result object go out of scope.
 	 *
-	 * @param $res Mixed: A SQL result
+	 * @param mixed $res A SQL result
 	 */
 	public function freeResult( $res ) {
 	}
@@ -1226,9 +1376,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Returns an optional USE INDEX clause to go after the table, and a
 	 * string to go at the end of the query.
 	 *
-	 * @param array $options associative array of options to be turned into
-	 *              an SQL query, valid keys are listed in the function.
-	 * @return Array
+	 * @param array $options Associative array of options to be turned into
+	 *   an SQL query, valid keys are listed in the function.
+	 * @return array
 	 * @see DatabaseBase::select()
 	 */
 	public function makeSelectOptions( $options ) {
@@ -1310,7 +1460,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Returns an optional GROUP BY with an optional HAVING
 	 *
-	 * @param array $options associative array of options
+	 * @param array $options Associative array of options
 	 * @return string
 	 * @see DatabaseBase::select()
 	 * @since 1.21
@@ -1329,13 +1479,14 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				: $options['HAVING'];
 			$sql .= ' HAVING ' . $having;
 		}
+
 		return $sql;
 	}
 
 	/**
 	 * Returns an optional ORDER BY
 	 *
-	 * @param array $options associative array of options
+	 * @param array $options Associative array of options
 	 * @return string
 	 * @see DatabaseBase::select()
 	 * @since 1.21
@@ -1345,8 +1496,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			$ob = is_array( $options['ORDER BY'] )
 				? implode( ',', $options['ORDER BY'] )
 				: $options['ORDER BY'];
+
 			return ' ORDER BY ' . $ob;
 		}
+
 		return '';
 	}
 
@@ -1359,9 +1512,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @param string|array $conds Conditions
 	 * @param string $fname Caller function name
 	 * @param array $options Query options
-	 * @param $join_conds Array Join conditions
+	 * @param array $join_conds Join conditions
 	 *
-	 * @param $table string|array
+	 *
+	 * @param string|array $table
 	 *
 	 * May be either an array of table names, or a single string holding a table
 	 * name. If an array is given, table aliases can be specified, for example:
@@ -1376,7 +1530,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * added, and various other table name mappings to be performed.
 	 *
 	 *
-	 * @param $vars string|array
+	 * @param string|array $vars
 	 *
 	 * May be either a field name or an array of field names. The field names
 	 * can be complete fragments of SQL, for direct inclusion into the SELECT
@@ -1390,7 +1544,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * DBMS-independent.
 	 *
 	 *
-	 * @param $conds string|array
+	 * @param string|array $conds
 	 *
 	 * May be either a string containing a single condition, or an array of
 	 * conditions. If an array is given, the conditions constructed from each
@@ -1415,7 +1569,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *    - DatabaseBase::conditional()
 	 *
 	 *
-	 * @param $options string|array
+	 * @param string|array $options
 	 *
 	 * Optional: Array of query options. Boolean options are specified by
 	 * including them in the array as a string value with a numeric key, for
@@ -1471,7 +1625,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *    - SQL_NO_CACHE
 	 *
 	 *
-	 * @param $join_conds string|array
+	 * @param string|array $join_conds
 	 *
 	 * Optional associative array of table-specific join conditions. In the
 	 * most common case, this is unnecessary, since the join condition can be
@@ -1484,7 +1638,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 *    array( 'page' => array( 'LEFT JOIN', 'page_latest=rev_id' ) )
 	 *
-	 * @return ResultWrapper. If the query returned no rows, a ResultWrapper
+	 * @return ResultWrapper|bool If the query returned no rows, a ResultWrapper
 	 *   with no rows in it will be returned. If there was a query error, a
 	 *   DBQueryError exception will be thrown, except if the "ignore errors"
 	 *   option was set, in which case false will be returned.
@@ -1507,14 +1661,14 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @param string|array $conds Conditions
 	 * @param string $fname Caller function name
 	 * @param string|array $options Query options
-	 * @param $join_conds string|array Join conditions
+	 * @param string|array $join_conds Join conditions
 	 *
 	 * @return string SQL query string.
 	 * @see DatabaseBase::select()
 	 */
 	public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__,
-		$options = array(), $join_conds = array() )
-	{
+		$options = array(), $join_conds = array()
+	) {
 		if ( is_array( $vars ) ) {
 			$vars = implode( ',', $this->fieldNamesWithAlias( $vars ) );
 		}
@@ -1573,13 +1727,13 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @param array $conds Conditions
 	 * @param string $fname Caller function name
 	 * @param string|array $options Query options
-	 * @param $join_conds array|string Join conditions
+	 * @param array|string $join_conds Join conditions
 	 *
-	 * @return object|bool
+	 * @return stdClass|bool
 	 */
 	public function selectRow( $table, $vars, $conds, $fname = __METHOD__,
-		$options = array(), $join_conds = array() )
-	{
+		$options = array(), $join_conds = array()
+	) {
 		$options = (array)$options;
 		$options['LIMIT'] = 1;
 		$res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
@@ -1598,7 +1752,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * Estimate rows in dataset.
+	 * Estimate the number of rows in dataset
 	 *
 	 * MySQL allows you to estimate the number of rows that would be returned
 	 * by a SELECT query, using EXPLAIN SELECT. The estimate is provided using
@@ -1610,16 +1764,16 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * Takes the same arguments as DatabaseBase::select().
 	 *
-	 * @param string $table table name
-	 * @param array|string $vars : unused
-	 * @param array|string $conds : filters on the table
-	 * @param string $fname function name for profiling
-	 * @param array $options options for select
-	 * @return Integer: row count
-	 */
-	public function estimateRowCount( $table, $vars = '*', $conds = '',
-		$fname = __METHOD__, $options = array() )
-	{
+	 * @param string $table Table name
+	 * @param string $vars Unused
+	 * @param array|string $conds Filters on the table
+	 * @param string $fname Function name for profiling
+	 * @param array $options Options for select
+	 * @return int Row count
+	 */
+	public function estimateRowCount(
+		$table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array()
+	) {
 		$rows = 0;
 		$res = $this->select( $table, array( 'rowcount' => 'COUNT(*)' ), $conds, $fname, $options );
 
@@ -1632,6 +1786,36 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
+	 * Get the number of rows in dataset
+	 *
+	 * This is useful when trying to do COUNT(*) but with a LIMIT for performance.
+	 *
+	 * Takes the same arguments as DatabaseBase::select().
+	 *
+	 * @param string $table Table name
+	 * @param string $vars Unused
+	 * @param array|string $conds Filters on the table
+	 * @param string $fname Function name for profiling
+	 * @param array $options Options for select
+	 * @return int Row count
+	 * @since 1.24
+	 */
+	public function selectRowCount(
+		$table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array()
+	) {
+		$rows = 0;
+		$sql = $this->selectSQLText( $table, '1', $conds, $fname, $options );
+		$res = $this->query( "SELECT COUNT(*) AS rowcount FROM ($sql) tmp_count" );
+
+		if ( $res ) {
+			$row = $this->fetchRow( $res );
+			$rows = ( isset( $row['rowcount'] ) ) ? $row['rowcount'] : 0;
+		}
+
+		return $rows;
+	}
+
+	/**
 	 * Removes most variables from an SQL query and replaces them with X or N for numbers.
 	 * It's only slightly flawed. Don't use for anything important.
 	 *
@@ -1653,9 +1837,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		# All newlines, tabs, etc replaced by single space
 		$sql = preg_replace( '/\s+/', ' ', $sql );
 
-		# All numbers => N
+		# All numbers => N,
+		# except the ones surrounded by characters, e.g. l10n
 		$sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
-		$sql = preg_replace( '/-?\d+/s', 'N', $sql );
+		$sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
 
 		return $sql;
 	}
@@ -1663,10 +1848,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Determines whether a field exists in a table
 	 *
-	 * @param string $table table name
-	 * @param string $field filed to check on that table
-	 * @param string $fname calling function name (optional)
-	 * @return Boolean: whether $table has filed $field
+	 * @param string $table Table name
+	 * @param string $field Filed to check on that table
+	 * @param string $fname Calling function name (optional)
+	 * @return bool Whether $table has filed $field
 	 */
 	public function fieldExists( $table, $field, $fname = __METHOD__ ) {
 		$info = $this->fieldInfo( $table, $field );
@@ -1679,10 +1864,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Usually throws a DBQueryError on failure
 	 * If errors are explicitly ignored, returns NULL on failure
 	 *
-	 * @param $table
-	 * @param $index
-	 * @param $fname string
-	 *
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return bool|null
 	 */
 	public function indexExists( $table, $index, $fname = __METHOD__ ) {
@@ -1701,9 +1885,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Query whether a given table exists
 	 *
-	 * @param $table string
-	 * @param $fname string
-	 *
+	 * @param string $table
+	 * @param string $fname
 	 * @return bool
 	 */
 	public function tableExists( $table, $fname = __METHOD__ ) {
@@ -1716,24 +1899,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * mysql_field_type() wrapper
-	 * @param $res
-	 * @param $index
-	 * @return string
-	 */
-	public function fieldType( $res, $index ) {
-		if ( $res instanceof ResultWrapper ) {
-			$res = $res->result;
-		}
-
-		return mysql_field_type( $res, $index );
-	}
-
-	/**
 	 * Determines if a given index is unique
 	 *
-	 * @param $table string
-	 * @param $index string
+	 * @param string $table
+	 * @param string $index
 	 *
 	 * @return bool
 	 */
@@ -1750,7 +1919,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Helper for DatabaseBase::insert().
 	 *
-	 * @param $options array
+	 * @param array $options
 	 * @return string
 	 */
 	protected function makeInsertOptions( $options ) {
@@ -1782,11 +1951,11 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *     possible to determine how many rows were successfully inserted using
 	 *     DatabaseBase::affectedRows().
 	 *
-	 * @param $table   String Table name. This will be passed through
-	 *                 DatabaseBase::tableName().
-	 * @param $a       Array of rows to insert
-	 * @param $fname   String Calling function name (use __METHOD__) for logs/profiling
-	 * @param array $options of options
+	 * @param string $table Table name. This will be passed through
+	 *   DatabaseBase::tableName().
+	 * @param array $a Array of rows to insert
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
+	 * @param array $options Array of options
 	 *
 	 * @return bool
 	 */
@@ -1843,12 +2012,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * Make UPDATE options for the DatabaseBase::update function
+	 * Make UPDATE options array for DatabaseBase::makeUpdateOptions
 	 *
-	 * @param array $options The options passed to DatabaseBase::update
-	 * @return string
+	 * @param array $options
+	 * @return array
 	 */
-	protected function makeUpdateOptions( $options ) {
+	protected function makeUpdateOptionsArray( $options ) {
 		if ( !is_array( $options ) ) {
 			$options = array( $options );
 		}
@@ -1863,31 +2032,38 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			$opts[] = 'IGNORE';
 		}
 
+		return $opts;
+	}
+
+	/**
+	 * Make UPDATE options for the DatabaseBase::update function
+	 *
+	 * @param array $options The options passed to DatabaseBase::update
+	 * @return string
+	 */
+	protected function makeUpdateOptions( $options ) {
+		$opts = $this->makeUpdateOptionsArray( $options );
+
 		return implode( ' ', $opts );
 	}
 
 	/**
 	 * UPDATE wrapper. Takes a condition array and a SET array.
 	 *
-	 * @param $table  String name of the table to UPDATE. This will be passed through
-	 *                DatabaseBase::tableName().
-	 *
-	 * @param array $values  An array of values to SET. For each array element,
-	 *                the key gives the field name, and the value gives the data
-	 *                to set that field to. The data will be quoted by
-	 *                DatabaseBase::addQuotes().
-	 *
-	 * @param $conds  Array:  An array of conditions (WHERE). See
-	 *                DatabaseBase::select() for the details of the format of
-	 *                condition arrays. Use '*' to update all rows.
-	 *
-	 * @param $fname  String: The function name of the caller (from __METHOD__),
-	 *                for logging and profiling.
-	 *
+	 * @param string $table Name of the table to UPDATE. This will be passed through
+	 *   DatabaseBase::tableName().
+	 * @param array $values An array of values to SET. For each array element,
+	 *   the key gives the field name, and the value gives the data to set
+	 *   that field to. The data will be quoted by DatabaseBase::addQuotes().
+	 * @param array $conds An array of conditions (WHERE). See
+	 *   DatabaseBase::select() for the details of the format of condition
+	 *   arrays. Use '*' to update all rows.
+	 * @param string $fname The function name of the caller (from __METHOD__),
+	 *   for logging and profiling.
 	 * @param array $options An array of UPDATE options, can be:
-	 *                   - IGNORE: Ignore unique key conflicts
-	 *                   - LOW_PRIORITY: MySQL-specific, see MySQL manual.
-	 * @return Boolean
+	 *   - IGNORE: Ignore unique key conflicts
+	 *   - LOW_PRIORITY: MySQL-specific, see MySQL manual.
+	 * @return bool
 	 */
 	function update( $table, $values, $conds, $fname = __METHOD__, $options = array() ) {
 		$table = $this->tableName( $table );
@@ -1903,15 +2079,15 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Makes an encoded list of strings from an array
-	 * @param array $a containing the data
-	 * @param int $mode Constant
-	 *      - LIST_COMMA:          comma separated, no field names
-	 *      - LIST_AND:            ANDed WHERE clause (without the WHERE). See
-	 *        the documentation for $conds in DatabaseBase::select().
-	 *      - LIST_OR:             ORed WHERE clause (without the WHERE)
-	 *      - LIST_SET:            comma separated with field names, like a SET clause
-	 *      - LIST_NAMES:          comma separated field names
 	 *
+	 * @param array $a Containing the data
+	 * @param int $mode Constant
+	 *    - LIST_COMMA: Comma separated, no field names
+	 *    - LIST_AND:   ANDed WHERE clause (without the WHERE). See the
+	 *      documentation for $conds in DatabaseBase::select().
+	 *    - LIST_OR:    ORed WHERE clause (without the WHERE)
+	 *    - LIST_SET:   Comma separated with field names, like a SET clause
+	 *    - LIST_NAMES: Comma separated field names
 	 * @throws MWException|DBUnexpectedError
 	 * @return string
 	 */
@@ -1974,11 +2150,11 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Build a partial where clause from a 2-d array such as used for LinkBatch.
 	 * The keys on each level may be either integers or strings.
 	 *
-	 * @param array $data organized as 2-d
-	 *              array(baseKeyVal => array(subKeyVal => [ignored], ...), ...)
-	 * @param string $baseKey field name to match the base-level keys to (eg 'pl_namespace')
-	 * @param string $subKey field name to match the sub-level keys to (eg 'pl_title')
-	 * @return Mixed: string SQL fragment, or false if no items in array.
+	 * @param array $data Organized as 2-d
+	 *    array(baseKeyVal => array(subKeyVal => [ignored], ...), ...)
+	 * @param string $baseKey Field name to match the base-level keys to (eg 'pl_namespace')
+	 * @param string $subKey Field name to match the sub-level keys to (eg 'pl_title')
+	 * @return string|bool SQL fragment, or false if no items in array
 	 */
 	public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
 		$conds = array();
@@ -2002,8 +2178,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Return aggregated value alias
 	 *
-	 * @param $valuedata
-	 * @param $valuename string
+	 * @param array $valuedata
+	 * @param string $valuename
 	 *
 	 * @return string
 	 */
@@ -2012,7 +2188,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * @param $field
+	 * @param string $field
 	 * @return string
 	 */
 	public function bitNot( $field ) {
@@ -2020,8 +2196,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * @param $fieldLeft
-	 * @param $fieldRight
+	 * @param string $fieldLeft
+	 * @param string $fieldRight
 	 * @return string
 	 */
 	public function bitAnd( $fieldLeft, $fieldRight ) {
@@ -2029,8 +2205,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * @param  $fieldLeft
-	 * @param  $fieldRight
+	 * @param string $fieldLeft
+	 * @param string $fieldRight
 	 * @return string
 	 */
 	public function bitOr( $fieldLeft, $fieldRight ) {
@@ -2039,32 +2215,59 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Build a concatenation list to feed into a SQL query
-	 * @param array $stringList list of raw SQL expressions; caller is responsible for any quoting
-	 * @return String
+	 * @param array $stringList List of raw SQL expressions; caller is
+	 *   responsible for any quoting
+	 * @return string
 	 */
 	public function buildConcat( $stringList ) {
 		return 'CONCAT(' . implode( ',', $stringList ) . ')';
 	}
 
 	/**
+	 * Build a GROUP_CONCAT or equivalent statement for a query.
+	 *
+	 * This is useful for combining a field for several rows into a single string.
+	 * NULL values will not appear in the output, duplicated values will appear,
+	 * and the resulting delimiter-separated values have no defined sort order.
+	 * Code using the results may need to use the PHP unique() or sort() methods.
+	 *
+	 * @param string $delim Glue to bind the results together
+	 * @param string|array $table Table name
+	 * @param string $field Field name
+	 * @param string|array $conds Conditions
+	 * @param string|array $join_conds Join conditions
+	 * @return string SQL text
+	 * @since 1.23
+	 */
+	public function buildGroupConcatField(
+		$delim, $table, $field, $conds = '', $join_conds = array()
+	) {
+		$fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
+
+		return '(' . $this->selectSQLText( $table, $fld, $conds, null, array(), $join_conds ) . ')';
+	}
+
+	/**
 	 * Change the current database
 	 *
 	 * @todo Explain what exactly will fail if this is not overridden.
 	 *
-	 * @param $db
+	 * @param string $db
 	 *
 	 * @return bool Success or failure
 	 */
 	public function selectDB( $db ) {
-		# Stub.  Shouldn't cause serious problems if it's not overridden, but
+		# Stub. Shouldn't cause serious problems if it's not overridden, but
 		# if your database engine supports a concept similar to MySQL's
 		# databases you may as well.
 		$this->mDBname = $db;
+
 		return true;
 	}
 
 	/**
 	 * Get the current DB name
+	 * @return string
 	 */
 	public function getDBname() {
 		return $this->mDBname;
@@ -2072,6 +2275,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Get the server hostname or IP address
+	 * @return string
 	 */
 	public function getServer() {
 		return $this->mServer;
@@ -2087,15 +2291,15 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * themselves. Pass the canonical name to such functions. This is only needed
 	 * when calling query() directly.
 	 *
-	 * @param string $name database table name
+	 * @param string $name Database table name
 	 * @param string $format One of:
 	 *   quoted - Automatically pass the table name through addIdentifierQuotes()
 	 *            so that it can be used in a query.
 	 *   raw - Do not add identifier quotes to the table name
-	 * @return String: full database name
+	 * @return string Full database name
 	 */
 	public function tableName( $name, $format = 'quoted' ) {
-		global $wgSharedDB, $wgSharedPrefix, $wgSharedTables;
+		global $wgSharedDB, $wgSharedPrefix, $wgSharedTables, $wgSharedSchema;
 		# Skip the entire process when we have a string quoted on both ends.
 		# Note that we check the end so that we will still quote any use of
 		# use of `database`.table. But won't break things if someone wants
@@ -2119,31 +2323,49 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		# We reverse the explode so that database.table and table both output
 		# the correct table.
 		$dbDetails = explode( '.', $name, 2 );
-		if ( count( $dbDetails ) == 2 ) {
+		if ( count( $dbDetails ) == 3 ) {
+			list( $database, $schema, $table ) = $dbDetails;
+			# We don't want any prefix added in this case
+			$prefix = '';
+		} elseif ( count( $dbDetails ) == 2 ) {
 			list( $database, $table ) = $dbDetails;
 			# We don't want any prefix added in this case
+			# In dbs that support it, $database may actually be the schema
+			# but that doesn't affect any of the functionality here
 			$prefix = '';
+			$schema = null;
 		} else {
 			list( $table ) = $dbDetails;
 			if ( $wgSharedDB !== null # We have a shared database
 				&& $this->mForeign == false # We're not working on a foreign database
-				&& !$this->isQuotedIdentifier( $table ) # Paranoia check to prevent shared tables listing '`table`'
+				&& !$this->isQuotedIdentifier( $table ) # Prevent shared tables listing '`table`'
 				&& in_array( $table, $wgSharedTables ) # A shared table is selected
 			) {
 				$database = $wgSharedDB;
+				$schema = $wgSharedSchema === null ? $this->mSchema : $wgSharedSchema;
 				$prefix = $wgSharedPrefix === null ? $this->mTablePrefix : $wgSharedPrefix;
 			} else {
 				$database = null;
+				$schema = $this->mSchema; # Default schema
 				$prefix = $this->mTablePrefix; # Default prefix
 			}
 		}
 
 		# Quote $table and apply the prefix if not quoted.
+		# $tableName might be empty if this is called from Database::replaceVars()
 		$tableName = "{$prefix}{$table}";
-		if ( $format == 'quoted' && !$this->isQuotedIdentifier( $tableName ) ) {
+		if ( $format == 'quoted' && !$this->isQuotedIdentifier( $tableName ) && $tableName !== '' ) {
 			$tableName = $this->addIdentifierQuotes( $tableName );
 		}
 
+		# Quote $schema and merge it with the table name if needed
+		if ( $schema !== null ) {
+			if ( $format == 'quoted' && !$this->isQuotedIdentifier( $schema ) ) {
+				$schema = $this->addIdentifierQuotes( $schema );
+			}
+			$tableName = $schema . '.' . $tableName;
+		}
+
 		# Quote $database and merge it with the table name if needed
 		if ( $database !== null ) {
 			if ( $format == 'quoted' && !$this->isQuotedIdentifier( $database ) ) {
@@ -2218,8 +2440,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Gets an array of aliased table names
 	 *
-	 * @param $tables array( [alias] => table )
-	 * @return array of strings, see tableNameWithAlias()
+	 * @param array $tables Array( [alias] => table )
+	 * @return string[] See tableNameWithAlias()
 	 */
 	public function tableNamesWithAlias( $tables ) {
 		$retval = array();
@@ -2229,6 +2451,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			}
 			$retval[] = $this->tableNameWithAlias( $table, $alias );
 		}
+
 		return $retval;
 	}
 
@@ -2251,8 +2474,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Gets an array of aliased field names
 	 *
-	 * @param $fields array( [alias] => field )
-	 * @return array of strings, see fieldNameWithAlias()
+	 * @param array $fields Array( [alias] => field )
+	 * @return string[] See fieldNameWithAlias()
 	 */
 	public function fieldNamesWithAlias( $fields ) {
 		$retval = array();
@@ -2262,6 +2485,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			}
 			$retval[] = $this->fieldNameWithAlias( $field, $alias );
 		}
+
 		return $retval;
 	}
 
@@ -2270,8 +2494,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * which might have a JOIN and/or USE INDEX clause
 	 *
 	 * @param array $tables ( [alias] => table )
-	 * @param $use_index array Same as for select()
-	 * @param $join_conds array Same as for select()
+	 * @param array $use_index Same as for select()
+	 * @param array $join_conds Same as for select()
 	 * @return string
 	 */
 	protected function tableNamesWithUseIndexOrJOIN(
@@ -2304,11 +2528,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				}
 
 				$retJOIN[] = $tableClause;
-			// Is there an INDEX clause for this table?
 			} elseif ( isset( $use_index[$alias] ) ) {
+				// Is there an INDEX clause for this table?
 				$tableClause = $this->tableNameWithAlias( $table, $alias );
 				$tableClause .= ' ' . $this->useIndexClause(
-					implode( ',', (array)$use_index[$alias] ) );
+					implode( ',', (array)$use_index[$alias] )
+				);
 
 				$ret[] = $tableClause;
 			} else {
@@ -2329,8 +2554,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Get the name of an index in a given table
 	 *
-	 * @param $index
-	 *
+	 * @param string $index
 	 * @return string
 	 */
 	protected function indexName( $index ) {
@@ -2351,8 +2575,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Adds quotes and backslashes.
 	 *
-	 * @param $s string
-	 *
+	 * @param string $s
 	 * @return string
 	 */
 	public function addQuotes( $s ) {
@@ -2373,8 +2596,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Since MySQL is the odd one out here the double quotes are our generic
 	 * and we implement backticks in DatabaseMysql.
 	 *
-	 * @param $s string
-	 *
+	 * @param string $s
 	 * @return string
 	 */
 	public function addIdentifierQuotes( $s ) {
@@ -2385,37 +2607,36 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Returns if the given identifier looks quoted or not according to
 	 * the database convention for quoting identifiers .
 	 *
-	 * @param $name string
-	 *
-	 * @return boolean
+	 * @param string $name
+	 * @return bool
 	 */
 	public function isQuotedIdentifier( $name ) {
 		return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
 	}
 
 	/**
-	 * @param $s string
+	 * @param string $s
 	 * @return string
 	 */
 	protected function escapeLikeInternal( $s ) {
-		$s = str_replace( '\\', '\\\\', $s );
-		$s = $this->strencode( $s );
-		$s = str_replace( array( '%', '_' ), array( '\%', '\_' ), $s );
-
-		return $s;
+		return addcslashes( $s, '\%_' );
 	}
 
 	/**
-	 * LIKE statement wrapper, receives a variable-length argument list with parts of pattern to match
-	 * containing either string literals that will be escaped or tokens returned by anyChar() or anyString().
-	 * Alternatively, the function could be provided with an array of aforementioned parameters.
+	 * LIKE statement wrapper, receives a variable-length argument list with
+	 * parts of pattern to match containing either string literals that will be
+	 * escaped or tokens returned by anyChar() or anyString(). Alternatively,
+	 * the function could be provided with an array of aforementioned
+	 * parameters.
 	 *
-	 * Example: $dbr->buildLike( 'My_page_title/', $dbr->anyString() ) returns a LIKE clause that searches
-	 * for subpages of 'My page title'.
-	 * Alternatively: $pattern = array( 'My_page_title/', $dbr->anyString() ); $query .= $dbr->buildLike( $pattern );
+	 * Example: $dbr->buildLike( 'My_page_title/', $dbr->anyString() ) returns
+	 * a LIKE clause that searches for subpages of 'My page title'.
+	 * Alternatively:
+	 *   $pattern = array( 'My_page_title/', $dbr->anyString() );
+	 *   $query .= $dbr->buildLike( $pattern );
 	 *
 	 * @since 1.16
-	 * @return String: fully built LIKE statement
+	 * @return string Fully built LIKE statement
 	 */
 	public function buildLike() {
 		$params = func_get_args();
@@ -2434,7 +2655,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			}
 		}
 
-		return " LIKE '" . $s . "' ";
+		return " LIKE {$this->addQuotes( $s )} ";
 	}
 
 	/**
@@ -2463,21 +2684,21 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Any implementation of this function should *not* involve reusing
 	 * sequence numbers created for rolled-back transactions.
 	 * See http://bugs.mysql.com/bug.php?id=30767 for details.
-	 * @param $seqName string
-	 * @return null
+	 * @param string $seqName
+	 * @return null|int
 	 */
 	public function nextSequenceValue( $seqName ) {
 		return null;
 	}
 
 	/**
-	 * USE INDEX clause.  Unlikely to be useful for anything but MySQL.  This
+	 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
 	 * is only needed because a) MySQL must be as efficient as possible due to
 	 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
-	 * which index to pick.  Anyway, other databases might have different
-	 * indexes on a given table.  So don't bother overriding this unless you're
+	 * which index to pick. Anyway, other databases might have different
+	 * indexes on a given table. So don't bother overriding this unless you're
 	 * MySQL.
-	 * @param $index
+	 * @param string $index
 	 * @return string
 	 */
 	public function useIndexClause( $index ) {
@@ -2500,10 +2721,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * errors which wouldn't have occurred in MySQL.
 	 *
 	 * @param string $table The table to replace the row(s) in.
+	 * @param array $uniqueIndexes Is an array of indexes. Each element may be either
+	 *    a field name or an array of field names
 	 * @param array $rows Can be either a single row to insert, or multiple rows,
 	 *    in the same format as for DatabaseBase::insert()
-	 * @param array $uniqueIndexes is an array of indexes. Each element may be either
-	 *    a field name or an array of field names
 	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
 	 */
 	public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
@@ -2558,7 +2779,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * statement.
 	 *
 	 * @param string $table Table name
-	 * @param array $rows Rows to insert
+	 * @param array|string $rows Row(s) to insert
 	 * @param string $fname Caller function name
 	 *
 	 * @return ResultWrapper
@@ -2609,26 +2830,28 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Usually throws a DBQueryError on failure. If errors are explicitly ignored,
 	 * returns success.
 	 *
+	 * @since 1.22
+	 *
 	 * @param string $table Table name. This will be passed through DatabaseBase::tableName().
 	 * @param array $rows A single row or list of rows to insert
 	 * @param array $uniqueIndexes List of single field names or field name tuples
-	 * @param array $set An array of values to SET. For each array element,
-	 *                the key gives the field name, and the value gives the data
-	 *                to set that field to. The data will be quoted by
-	 *                DatabaseBase::addQuotes().
+	 * @param array $set An array of values to SET. For each array element, the
+	 *   key gives the field name, and the value gives the data to set that
+	 *   field to. The data will be quoted by DatabaseBase::addQuotes().
 	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
-	 * @param array $options of options
-	 *
+	 * @throws Exception
 	 * @return bool
-	 * @since 1.22
 	 */
-	public function upsert(
-		$table, array $rows, array $uniqueIndexes, array $set, $fname = __METHOD__
+	public function upsert( $table, array $rows, array $uniqueIndexes, array $set,
+		$fname = __METHOD__
 	) {
 		if ( !count( $rows ) ) {
 			return true; // nothing to do
 		}
-		$rows = is_array( reset( $rows ) ) ? $rows : array( $rows );
+
+		if ( !is_array( reset( $rows ) ) ) {
+			$rows = array( $rows );
+		}
 
 		if ( count( $uniqueIndexes ) ) {
 			$clauses = array(); // list WHERE clauses that each identify a single row
@@ -2684,19 +2907,18 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * DO NOT put the join condition in $conds.
 	 *
-	 * @param $delTable   String: The table to delete from.
-	 * @param $joinTable  String: The other table.
-	 * @param $delVar     String: The variable to join on, in the first table.
-	 * @param $joinVar    String: The variable to join on, in the second table.
-	 * @param $conds      Array: Condition array of field names mapped to variables,
-	 *                    ANDed together in the WHERE clause
-	 * @param $fname      String: Calling function name (use __METHOD__) for
-	 *                    logs/profiling
+	 * @param string $delTable The table to delete from.
+	 * @param string $joinTable The other table.
+	 * @param string $delVar The variable to join on, in the first table.
+	 * @param string $joinVar The variable to join on, in the second table.
+	 * @param array $conds Condition array of field names mapped to variables,
+	 *   ANDed together in the WHERE clause
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
 	 * @throws DBUnexpectedError
 	 */
 	public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
-		$fname = __METHOD__ )
-	{
+		$fname = __METHOD__
+	) {
 		if ( !$conds ) {
 			throw new DBUnexpectedError( $this,
 				'DatabaseBase::deleteJoin() called with empty $conds' );
@@ -2716,9 +2938,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Returns the size of a text field, or -1 for "unlimited"
 	 *
-	 * @param $table string
-	 * @param $field string
-	 *
+	 * @param string $table
+	 * @param string $field
 	 * @return int
 	 */
 	public function textFieldSize( $table, $field ) {
@@ -2740,7 +2961,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * A string to insert into queries to show that they're low-priority, like
-	 * MySQL's LOW_PRIORITY.  If no such feature exists, return an empty
+	 * MySQL's LOW_PRIORITY. If no such feature exists, return an empty
 	 * string and nothing bad should happen.
 	 *
 	 * @return string Returns the text of the low priority option if it is
@@ -2754,10 +2975,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * DELETE query wrapper.
 	 *
 	 * @param array $table Table name
-	 * @param string|array $conds of conditions. See $conds in DatabaseBase::select() for
-	 *               the format. Use $conds == "*" to delete all rows
-	 * @param string $fname name of the calling function
-	 *
+	 * @param string|array $conds Array of conditions. See $conds in DatabaseBase::select()
+	 *   for the format. Use $conds == "*" to delete all rows
+	 * @param string $fname Name of the calling function
 	 * @throws DBUnexpectedError
 	 * @return bool|ResultWrapper
 	 */
@@ -2787,7 +3007,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @param string|array $srcTable May be either a table name, or an array of table names
 	 *    to include in a join.
 	 *
-	 * @param array $varMap must be an associative array of the form
+	 * @param array $varMap Must be an associative array of the form
 	 *    array( 'dest1' => 'source1', ...). Source items may be literals
 	 *    rather than field names, but strings should be quoted with
 	 *    DatabaseBase::addQuotes()
@@ -2807,14 +3027,16 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 */
 	public function insertSelect( $destTable, $srcTable, $varMap, $conds,
 		$fname = __METHOD__,
-		$insertOptions = array(), $selectOptions = array() )
-	{
+		$insertOptions = array(), $selectOptions = array()
+	) {
 		$destTable = $this->tableName( $destTable );
 
-		if ( is_array( $insertOptions ) ) {
-			$insertOptions = implode( ' ', $insertOptions );
+		if ( !is_array( $insertOptions ) ) {
+			$insertOptions = array( $insertOptions );
 		}
 
+		$insertOptions = $this->makeInsertOptions( $insertOptions );
+
 		if ( !is_array( $selectOptions ) ) {
 			$selectOptions = array( $selectOptions );
 		}
@@ -2844,22 +3066,21 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * Construct a LIMIT query with optional offset.  This is used for query
-	 * pages.  The SQL should be adjusted so that only the first $limit rows
-	 * are returned.  If $offset is provided as well, then the first $offset
+	 * Construct a LIMIT query with optional offset. This is used for query
+	 * pages. The SQL should be adjusted so that only the first $limit rows
+	 * are returned. If $offset is provided as well, then the first $offset
 	 * rows should be discarded, and the next $limit rows should be returned.
 	 * If the result of the query is not ordered, then the rows to be returned
 	 * are theoretically arbitrary.
 	 *
 	 * $sql is expected to be a SELECT, if that makes a difference.
 	 *
-	 * The version provided by default works in MySQL and SQLite.  It will very
+	 * The version provided by default works in MySQL and SQLite. It will very
 	 * likely need to be overridden for most other DBMSes.
 	 *
 	 * @param string $sql SQL query we will append the limit too
-	 * @param $limit Integer the SQL limit
-	 * @param $offset Integer|bool the SQL offset (default false)
-	 *
+	 * @param int $limit The SQL limit
+	 * @param int|bool $offset The SQL offset (default false)
 	 * @throws DBUnexpectedError
 	 * @return string
 	 */
@@ -2867,6 +3088,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		if ( !is_numeric( $limit ) ) {
 			throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" );
 		}
+
 		return "$sql LIMIT "
 			. ( ( is_numeric( $offset ) && $offset != 0 ) ? "{$offset}," : "" )
 			. "{$limit} ";
@@ -2875,7 +3097,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Returns true if current database backend supports ORDER BY or LIMIT for separate subqueries
 	 * within the UNION construct.
-	 * @return Boolean
+	 * @return bool
 	 */
 	public function unionSupportsOrderAndLimit() {
 		return true; // True for almost every DB supported
@@ -2886,27 +3108,29 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * This is used for providing overload point for other DB abstractions
 	 * not compatible with the MySQL syntax.
 	 * @param array $sqls SQL statements to combine
-	 * @param $all Boolean: use UNION ALL
-	 * @return String: SQL fragment
+	 * @param bool $all Use UNION ALL
+	 * @return string SQL fragment
 	 */
 	public function unionQueries( $sqls, $all ) {
 		$glue = $all ? ') UNION ALL (' : ') UNION (';
+
 		return '(' . implode( $glue, $sqls ) . ')';
 	}
 
 	/**
-	 * Returns an SQL expression for a simple conditional.  This doesn't need
+	 * Returns an SQL expression for a simple conditional. This doesn't need
 	 * to be overridden unless CASE isn't supported in your DBMS.
 	 *
 	 * @param string|array $cond SQL expression which will result in a boolean value
 	 * @param string $trueVal SQL expression to return if true
 	 * @param string $falseVal SQL expression to return if false
-	 * @return String: SQL fragment
+	 * @return string SQL fragment
 	 */
 	public function conditional( $cond, $trueVal, $falseVal ) {
 		if ( is_array( $cond ) ) {
 			$cond = $this->makeList( $cond, LIST_AND );
 		}
+
 		return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
 	}
 
@@ -2914,9 +3138,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Returns a comand for str_replace function in SQL query.
 	 * Uses REPLACE() in MySQL
 	 *
-	 * @param string $orig column to modify
-	 * @param string $old column to seek
-	 * @param string $new column to replace with
+	 * @param string $orig Column to modify
+	 * @param string $old Column to seek
+	 * @param string $new Column to replace with
 	 *
 	 * @return string
 	 */
@@ -3027,9 +3251,11 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		if ( $tries <= 0 ) {
 			$this->rollback( __METHOD__ );
 			$this->reportQueryError( $error, $errno, $sql, $fname );
+
 			return false;
 		} else {
 			$this->commit( __METHOD__ );
+
 			return $retVal;
 		}
 	}
@@ -3037,38 +3263,14 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Wait for the slave to catch up to a given master position.
 	 *
-	 * @param $pos DBMasterPos object
-	 * @param $timeout Integer: the maximum number of seconds to wait for
+	 * @param DBMasterPos $pos
+	 * @param int $timeout The maximum number of seconds to wait for
 	 *   synchronisation
-	 *
-	 * @return integer: zero if the slave was past that position already,
+	 * @return int Zero if the slave was past that position already,
 	 *   greater than zero if we waited for some period of time, less than
 	 *   zero if we timed out.
 	 */
 	public function masterPosWait( DBMasterPos $pos, $timeout ) {
-		wfProfileIn( __METHOD__ );
-
-		if ( !is_null( $this->mFakeSlaveLag ) ) {
-			$wait = intval( ( $pos->pos - microtime( true ) + $this->mFakeSlaveLag ) * 1e6 );
-
-			if ( $wait > $timeout * 1e6 ) {
-				wfDebug( "Fake slave timed out waiting for $pos ($wait us)\n" );
-				wfProfileOut( __METHOD__ );
-				return -1;
-			} elseif ( $wait > 0 ) {
-				wfDebug( "Fake slave waiting $wait us\n" );
-				usleep( $wait );
-				wfProfileOut( __METHOD__ );
-				return 1;
-			} else {
-				wfDebug( "Fake slave up to date ($wait us)\n" );
-				wfProfileOut( __METHOD__ );
-				return 0;
-			}
-		}
-
-		wfProfileOut( __METHOD__ );
-
 		# Real waits are implemented in the subclass.
 		return 0;
 	}
@@ -3076,30 +3278,21 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Get the replication position of this slave
 	 *
-	 * @return DBMasterPos, or false if this is not a slave.
+	 * @return DBMasterPos|bool False if this is not a slave.
 	 */
 	public function getSlavePos() {
-		if ( !is_null( $this->mFakeSlaveLag ) ) {
-			$pos = new MySQLMasterPos( 'fake', microtime( true ) - $this->mFakeSlaveLag );
-			wfDebug( __METHOD__ . ": fake slave pos = $pos\n" );
-			return $pos;
-		} else {
-			# Stub
-			return false;
-		}
+		# Stub
+		return false;
 	}
 
 	/**
 	 * Get the position of this master
 	 *
-	 * @return DBMasterPos, or false if this is not a master
+	 * @return DBMasterPos|bool False if this is not a master
 	 */
 	public function getMasterPos() {
-		if ( $this->mFakeMaster ) {
-			return new MySQLMasterPos( 'fake', microtime( true ) );
-		} else {
-			return false;
-		}
+		# Stub
+		return false;
 	}
 
 	/**
@@ -3150,7 +3343,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	protected function runOnTransactionIdleCallbacks() {
 		$autoTrx = $this->getFlag( DBO_TRX ); // automatic begin() enabled?
 
-		$e = null; // last exception
+		$e = $ePrior = null; // last exception
 		do { // callbacks may add callbacks :)
 			$callbacks = $this->mTrxIdleCallbacks;
 			$this->mTrxIdleCallbacks = array(); // recursion guard
@@ -3160,7 +3353,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 					$this->clearFlag( DBO_TRX ); // make each query its own transaction
 					call_user_func( $phpCallback );
 					$this->setFlag( $autoTrx ? DBO_TRX : 0 ); // restore automatic begin()
-				} catch ( Exception $e ) {}
+				} catch ( Exception $e ) {
+					if ( $ePrior ) {
+						MWExceptionHandler::logException( $ePrior );
+					}
+					$ePrior = $e;
+				}
 			}
 		} while ( count( $this->mTrxIdleCallbacks ) );
 
@@ -3175,7 +3373,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @since 1.22
 	 */
 	protected function runOnTransactionPreCommitCallbacks() {
-		$e = null; // last exception
+		$e = $ePrior = null; // last exception
 		do { // callbacks may add callbacks :)
 			$callbacks = $this->mTrxPreCommitCallbacks;
 			$this->mTrxPreCommitCallbacks = array(); // recursion guard
@@ -3183,7 +3381,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				try {
 					list( $phpCallback ) = $callback;
 					call_user_func( $phpCallback );
-				} catch ( Exception $e ) {}
+				} catch ( Exception $e ) {
+					if ( $ePrior ) {
+						MWExceptionHandler::logException( $ePrior );
+					}
+					$ePrior = $e;
+				}
 			}
 		} while ( count( $this->mTrxPreCommitCallbacks ) );
 
@@ -3193,22 +3396,91 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	}
 
 	/**
-	 * Begin a transaction. If a transaction is already in progress, that transaction will be committed before the
-	 * new transaction is started.
+	 * Begin an atomic section of statements
+	 *
+	 * If a transaction has been started already, just keep track of the given
+	 * section name to make sure the transaction is not committed pre-maturely.
+	 * This function can be used in layers (with sub-sections), so use a stack
+	 * to keep track of the different atomic sections. If there is no transaction,
+	 * start one implicitly.
+	 *
+	 * The goal of this function is to create an atomic section of SQL queries
+	 * without having to start a new transaction if it already exists.
 	 *
-	 * Note that when the DBO_TRX flag is set (which is usually the case for web requests, but not for maintenance scripts),
-	 * any previous database query will have started a transaction automatically.
+	 * Atomic sections are more strict than transactions. With transactions,
+	 * attempting to begin a new transaction when one is already running results
+	 * in MediaWiki issuing a brief warning and doing an implicit commit. All
+	 * atomic levels *must* be explicitly closed using DatabaseBase::endAtomic(),
+	 * and any database transactions cannot be began or committed until all atomic
+	 * levels are closed. There is no such thing as implicitly opening or closing
+	 * an atomic section.
+	 *
+	 * @since 1.23
+	 * @param string $fname
+	 * @throws DBError
+	 */
+	final public function startAtomic( $fname = __METHOD__ ) {
+		if ( !$this->mTrxLevel ) {
+			$this->begin( $fname );
+			$this->mTrxAutomatic = true;
+			$this->mTrxAutomaticAtomic = true;
+		}
+
+		$this->mTrxAtomicLevels->push( $fname );
+	}
+
+	/**
+	 * Ends an atomic section of SQL statements
 	 *
-	 * Nesting of transactions is not supported. Attempts to nest transactions will cause a warning, unless the current
-	 * transaction was started automatically because of the DBO_TRX flag.
+	 * Ends the next section of atomic SQL statements and commits the transaction
+	 * if necessary.
 	 *
-	 * @param $fname string
+	 * @since 1.23
+	 * @see DatabaseBase::startAtomic
+	 * @param string $fname
+	 * @throws DBError
+	 */
+	final public function endAtomic( $fname = __METHOD__ ) {
+		if ( !$this->mTrxLevel ) {
+			throw new DBUnexpectedError( $this, 'No atomic transaction is open.' );
+		}
+		if ( $this->mTrxAtomicLevels->isEmpty() ||
+			$this->mTrxAtomicLevels->pop() !== $fname
+		) {
+			throw new DBUnexpectedError( $this, 'Invalid atomic section ended.' );
+		}
+
+		if ( $this->mTrxAtomicLevels->isEmpty() && $this->mTrxAutomaticAtomic ) {
+			$this->commit( $fname, 'flush' );
+		}
+	}
+
+	/**
+	 * Begin a transaction. If a transaction is already in progress,
+	 * that transaction will be committed before the new transaction is started.
+	 *
+	 * Note that when the DBO_TRX flag is set (which is usually the case for web
+	 * requests, but not for maintenance scripts), any previous database query
+	 * will have started a transaction automatically.
+	 *
+	 * Nesting of transactions is not supported. Attempts to nest transactions
+	 * will cause a warning, unless the current transaction was started
+	 * automatically because of the DBO_TRX flag.
+	 *
+	 * @param string $fname
+	 * @throws DBError
 	 */
 	final public function begin( $fname = __METHOD__ ) {
 		global $wgDebugDBTransactions;
 
 		if ( $this->mTrxLevel ) { // implicit commit
-			if ( !$this->mTrxAutomatic ) {
+			if ( !$this->mTrxAtomicLevels->isEmpty() ) {
+				// If the current transaction was an automatic atomic one, then we definitely have
+				// a problem. Same if there is any unclosed atomic level.
+				throw new DBUnexpectedError( $this,
+					"Attempted to start explicit transaction when atomic levels are still open."
+				);
+			} elseif ( !$this->mTrxAutomatic ) {
 				// We want to warn about inadvertently nested begin/commit pairs, but not about
 				// auto-committing implicit transactions that were started by query() via DBO_TRX
 				$msg = "$fname: Transaction already in progress (from {$this->mTrxFname}), " .
@@ -3228,22 +3500,33 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			$this->runOnTransactionPreCommitCallbacks();
 			$this->doCommit( $fname );
 			if ( $this->mTrxDoneWrites ) {
-				Profiler::instance()->transactionWritingOut( $this->mServer, $this->mDBname );
+				Profiler::instance()->transactionWritingOut(
+					$this->mServer, $this->mDBname, $this->mTrxShortId );
 			}
 			$this->runOnTransactionIdleCallbacks();
 		}
 
+		# Avoid fatals if close() was called
+		if ( !$this->isOpen() ) {
+			throw new DBUnexpectedError( $this, "DB connection was already closed." );
+		}
+
 		$this->doBegin( $fname );
 		$this->mTrxFname = $fname;
 		$this->mTrxDoneWrites = false;
 		$this->mTrxAutomatic = false;
+		$this->mTrxAutomaticAtomic = false;
+		$this->mTrxAtomicLevels = new SplStack;
+		$this->mTrxIdleCallbacks = array();
+		$this->mTrxPreCommitCallbacks = array();
+		$this->mTrxShortId = wfRandomString( 12 );
 	}
 
 	/**
 	 * Issues the BEGIN command to the database server.
 	 *
 	 * @see DatabaseBase::begin()
-	 * @param type $fname
+	 * @param string $fname
 	 */
 	protected function doBegin( $fname ) {
 		$this->query( 'BEGIN', $fname );
@@ -3256,33 +3539,49 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * Nesting of transactions is not supported.
 	 *
-	 * @param $fname string
-	 * @param string $flush Flush flag, set to 'flush' to disable warnings about explicitly committing implicit
-	 *        transactions, or calling commit when no transaction is in progress.
-	 *        This will silently break any ongoing explicit transaction. Only set the flush flag if you are sure
-	 *        that it is safe to ignore these warnings in your context.
+	 * @param string $fname
+	 * @param string $flush Flush flag, set to 'flush' to disable warnings about
+	 *   explicitly committing implicit transactions, or calling commit when no
+	 *   transaction is in progress. This will silently break any ongoing
+	 *   explicit transaction. Only set the flush flag if you are sure that it
+	 *   is safe to ignore these warnings in your context.
+	 * @throws DBUnexpectedError
 	 */
 	final public function commit( $fname = __METHOD__, $flush = '' ) {
-		if ( $flush != 'flush' ) {
+		if ( !$this->mTrxAtomicLevels->isEmpty() ) {
+			// There are still atomic sections open. This cannot be ignored
+			throw new DBUnexpectedError(
+				$this,
+				"Attempted to commit transaction while atomic sections are still open"
+			);
+		}
+
+		if ( $flush === 'flush' ) {
 			if ( !$this->mTrxLevel ) {
-				wfWarn( "$fname: No transaction to commit, something got out of sync!" );
-			} elseif ( $this->mTrxAutomatic ) {
-				wfWarn( "$fname: Explicit commit of implicit transaction. Something may be out of sync!" );
+				return; // nothing to do
+			} elseif ( !$this->mTrxAutomatic ) {
+				wfWarn( "$fname: Flushing an explicit transaction, getting out of sync!" );
 			}
 		} else {
 			if ( !$this->mTrxLevel ) {
+				wfWarn( "$fname: No transaction to commit, something got out of sync!" );
 				return; // nothing to do
-			} elseif ( !$this->mTrxAutomatic ) {
-				wfWarn( "$fname: Flushing an explicit transaction, getting out of sync!" );
+			} elseif ( $this->mTrxAutomatic ) {
+				wfWarn( "$fname: Explicit commit of implicit transaction. Something may be out of sync!" );
 			}
 		}
 
+		# Avoid fatals if close() was called
+		if ( !$this->isOpen() ) {
+			throw new DBUnexpectedError( $this, "DB connection was already closed." );
+		}
+
 		$this->runOnTransactionPreCommitCallbacks();
 		$this->doCommit( $fname );
 		if ( $this->mTrxDoneWrites ) {
-			Profiler::instance()->transactionWritingOut( $this->mServer, $this->mDBname );
+			Profiler::instance()->transactionWritingOut(
+				$this->mServer, $this->mDBname, $this->mTrxShortId );
 		}
-		$this->mTrxDoneWrites = false;
 		$this->runOnTransactionIdleCallbacks();
 	}
 
@@ -3290,7 +3589,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Issues the COMMIT command to the database server.
 	 *
 	 * @see DatabaseBase::commit()
-	 * @param type $fname
+	 * @param string $fname
 	 */
 	protected function doCommit( $fname ) {
 		if ( $this->mTrxLevel ) {
@@ -3305,26 +3604,49 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * No-op on non-transactional databases.
 	 *
-	 * @param $fname string
+	 * @param string $fname
+	 * @param string $flush Flush flag, set to 'flush' to disable warnings about
+	 *   calling rollback when no transaction is in progress. This will silently
+	 *   break any ongoing explicit transaction. Only set the flush flag if you
+	 *   are sure that it is safe to ignore these warnings in your context.
+	 * @since 1.23 Added $flush parameter
 	 */
-	final public function rollback( $fname = __METHOD__ ) {
-		if ( !$this->mTrxLevel ) {
-			wfWarn( "$fname: No transaction to rollback, something got out of sync!" );
+	final public function rollback( $fname = __METHOD__, $flush = '' ) {
+		if ( $flush !== 'flush' ) {
+			if ( !$this->mTrxLevel ) {
+				wfWarn( "$fname: No transaction to rollback, something got out of sync!" );
+				return; // nothing to do
+			} elseif ( $this->mTrxAutomatic ) {
+				wfWarn( "$fname: Explicit rollback of implicit transaction. Something may be out of sync!" );
+			}
+		} else {
+			if ( !$this->mTrxLevel ) {
+				return; // nothing to do
+			} elseif ( !$this->mTrxAutomatic ) {
+				wfWarn( "$fname: Flushing an explicit transaction, getting out of sync!" );
+			}
 		}
+
+		# Avoid fatals if close() was called
+		if ( !$this->isOpen() ) {
+			throw new DBUnexpectedError( $this, "DB connection was already closed." );
+		}
+
 		$this->doRollback( $fname );
 		$this->mTrxIdleCallbacks = array(); // cancel
 		$this->mTrxPreCommitCallbacks = array(); // cancel
+		$this->mTrxAtomicLevels = new SplStack;
 		if ( $this->mTrxDoneWrites ) {
-			Profiler::instance()->transactionWritingOut( $this->mServer, $this->mDBname );
+			Profiler::instance()->transactionWritingOut(
+				$this->mServer, $this->mDBname, $this->mTrxShortId );
 		}
-		$this->mTrxDoneWrites = false;
 	}
 
 	/**
 	 * Issues the ROLLBACK command to the database server.
 	 *
 	 * @see DatabaseBase::rollback()
-	 * @param type $fname
+	 * @param string $fname
 	 */
 	protected function doRollback( $fname ) {
 		if ( $this->mTrxLevel ) {
@@ -3341,12 +3663,12 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * The table names passed to this function shall not be quoted (this
 	 * function calls addIdentifierQuotes when needed).
 	 *
-	 * @param string $oldName name of table whose structure should be copied
-	 * @param string $newName name of table to be created
-	 * @param $temporary Boolean: whether the new table should be temporary
-	 * @param string $fname calling function name
+	 * @param string $oldName Name of table whose structure should be copied
+	 * @param string $newName Name of table to be created
+	 * @param bool $temporary Whether the new table should be temporary
+	 * @param string $fname Calling function name
 	 * @throws MWException
-	 * @return Boolean: true if operation was successful
+	 * @return bool True if operation was successful
 	 */
 	public function duplicateTableStructure( $oldName, $newName, $temporary = false,
 		$fname = __METHOD__
@@ -3359,7 +3681,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * List all tables on the database
 	 *
 	 * @param string $prefix Only show tables with this prefix, e.g. mw_
-	 * @param string $fname calling function name
+	 * @param string $fname Calling function name
 	 * @throws MWException
 	 */
 	function listTables( $prefix = null, $fname = __METHOD__ ) {
@@ -3380,8 +3702,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * For caching purposes the list of all views should be stored in
 	 * $this->allViews. The process cache can be cleared with clearViewsCache()
 	 *
-	 * @param string $prefix   Only show VIEWs with this prefix, eg. unit_test_
-	 * @param string $fname    Name of calling function
+	 * @param string $prefix Only show VIEWs with this prefix, eg. unit_test_
+	 * @param string $fname Name of calling function
 	 * @throws MWException
 	 * @since 1.22
 	 */
@@ -3392,7 +3714,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Differentiates between a TABLE and a VIEW
 	 *
-	 * @param $name string: Name of the database-structure to test.
+	 * @param string $name Name of the database-structure to test.
 	 * @throws MWException
 	 * @since 1.22
 	 */
@@ -3407,7 +3729,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * The result is unquoted, and needs to be passed through addQuotes()
 	 * before it can be included in raw SQL.
 	 *
-	 * @param $ts string|int
+	 * @param string|int $ts
 	 *
 	 * @return string
 	 */
@@ -3424,7 +3746,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * The result is unquoted, and needs to be passed through addQuotes()
 	 * before it can be included in raw SQL.
 	 *
-	 * @param $ts string|int
+	 * @param string|int $ts
 	 *
 	 * @return string
 	 */
@@ -3447,8 +3769,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * callers, so this is unnecessary in external code. For compatibility with
 	 * old code, ResultWrapper objects are passed through unaltered.
 	 *
-	 * @param $result bool|ResultWrapper
-	 *
+	 * @param bool|ResultWrapper|resource $result
 	 * @return bool|ResultWrapper
 	 */
 	public function resultObject( $result ) {
@@ -3470,7 +3791,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @return bool Success or failure
 	 */
 	public function ping() {
-		# Stub.  Not essential to override.
+		# Stub. Not essential to override.
 		return true;
 	}
 
@@ -3484,7 +3805,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @return int Database replication lag in seconds
 	 */
 	public function getLag() {
-		return intval( $this->mFakeSlaveLag );
+		return 0;
 	}
 
 	/**
@@ -3501,7 +3822,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * don't allow simple quoted strings to be inserted. To insert into such
 	 * a field, pass the data through this function before passing it to
 	 * DatabaseBase::insert().
-	 * @param $b string
+	 *
+	 * @param string $b
 	 * @return string
 	 */
 	public function encodeBlob( $b ) {
@@ -3512,7 +3834,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Some DBMSs return a special placeholder object representing blob fields
 	 * in result objects. Pass the object through this function to return the
 	 * original string.
-	 * @param $b string
+	 *
+	 * @param string $b
 	 * @return string
 	 */
 	public function decodeBlob( $b ) {
@@ -3526,7 +3849,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *                     full-wiki dumps, where a single query reads out over
 	 *                     hours or days.
 	 *
-	 * @param $options Array
+	 * @param array $options
 	 * @return void
 	 */
 	public function setSessionOptions( array $options ) {
@@ -3542,9 +3865,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * @param bool|callable $lineCallback Optional function called before reading each line
 	 * @param bool|callable $resultCallback Optional function called for each MySQL result
 	 * @param bool|string $fname Calling function name or false if name should be
-	 *      generated dynamically using $filename
-	 * @param bool|callable $inputCallback Callback: Optional function called for each complete line sent
-	 * @throws MWException
+	 *   generated dynamically using $filename
+	 * @param bool|callable $inputCallback Optional function called for each
+	 *   complete line sent
 	 * @throws Exception|MWException
 	 * @return bool|string
 	 */
@@ -3565,8 +3888,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 		try {
 			$error = $this->sourceStream( $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
-		}
-		catch ( MWException $e ) {
+		} catch ( MWException $e ) {
 			fclose( $fp );
 			throw $e;
 		}
@@ -3582,7 +3904,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * it fails back to MySQL if no DB-specific patch can be found
 	 *
 	 * @param string $patch The name of the patch, like patch-something.sql
-	 * @return String Full path to patch file
+	 * @return string Full path to patch file
 	 */
 	public function patchPath( $patch ) {
 		global $IP;
@@ -3600,7 +3922,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * ones in $GLOBALS. If an array is set here, $GLOBALS will not be used at
 	 * all. If it's set to false, $GLOBALS will be used.
 	 *
-	 * @param bool|array $vars mapping variable name to value.
+	 * @param bool|array $vars Mapping variable name to value.
 	 */
 	public function setSchemaVars( $vars ) {
 		$this->mSchemaVars = $vars;
@@ -3612,16 +3934,16 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Returns true on success, error string or exception on failure (depending
 	 * on object's error ignore settings).
 	 *
-	 * @param $fp Resource: File handle
-	 * @param $lineCallback Callback: Optional function called before reading each query
-	 * @param $resultCallback Callback: Optional function called for each MySQL result
+	 * @param resource $fp File handle
+	 * @param bool|callable $lineCallback Optional function called before reading each query
+	 * @param bool|callable $resultCallback Optional function called for each MySQL result
 	 * @param string $fname Calling function name
-	 * @param $inputCallback Callback: Optional function called for each complete query sent
+	 * @param bool|callable $inputCallback Optional function called for each complete query sent
 	 * @return bool|string
 	 */
 	public function sourceStream( $fp, $lineCallback = false, $resultCallback = false,
-		$fname = __METHOD__, $inputCallback = false )
-	{
+		$fname = __METHOD__, $inputCallback = false
+	) {
 		$cmd = '';
 
 		while ( !feof( $fp ) ) {
@@ -3659,6 +3981,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 					if ( false === $res ) {
 						$err = $this->lastError();
+
 						return "Query \"{$cmd}\" failed with error code \"$err\".\n";
 					}
 				}
@@ -3674,7 +3997,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * @param string $sql SQL assembled so far
 	 * @param string $newLine New line about to be added to $sql
-	 * @return Bool Whether $newLine contains end of the statement
+	 * @return bool Whether $newLine contains end of the statement
 	 */
 	public function streamStatementEnd( &$sql, &$newLine ) {
 		if ( $this->delimiter ) {
@@ -3684,6 +4007,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 				return true;
 			}
 		}
+
 		return false;
 	}
 
@@ -3702,7 +4026,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *   table options its use should be avoided.
 	 *
 	 * @param string $ins SQL statement to replace variables in
-	 * @return String The new SQL statement with variables replaced
+	 * @return string The new SQL statement with variables replaced
 	 */
 	protected function replaceSchemaVars( $ins ) {
 		$vars = $this->getSchemaVars();
@@ -3714,14 +4038,14 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			// replace /*$var*/
 			$ins = str_replace( '/*$' . $var . '*/', $this->strencode( $value ), $ins );
 		}
+
 		return $ins;
 	}
 
 	/**
 	 * Replace variables in sourced SQL
 	 *
-	 * @param $ins string
-	 *
+	 * @param string $ins
 	 * @return string
 	 */
 	protected function replaceVars( $ins ) {
@@ -3767,8 +4091,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Table name callback
 	 *
-	 * @param $matches array
-	 *
+	 * @param array $matches
 	 * @return string
 	 */
 	protected function tableNameCallback( $matches ) {
@@ -3778,8 +4101,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Index name callback
 	 *
-	 * @param $matches array
-	 *
+	 * @param array $matches
 	 * @return string
 	 */
 	protected function indexNameCallback( $matches ) {
@@ -3789,9 +4111,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Check to see if a named lock is available. This is non-blocking.
 	 *
-	 * @param string $lockName name of lock to poll
-	 * @param string $method name of method calling us
-	 * @return Boolean
+	 * @param string $lockName Name of lock to poll
+	 * @param string $method Name of method calling us
+	 * @return bool
 	 * @since 1.20
 	 */
 	public function lockIsFree( $lockName, $method ) {
@@ -3804,10 +4126,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Abstracted from Filestore::lock() so child classes can implement for
 	 * their own needs.
 	 *
-	 * @param string $lockName name of lock to aquire
-	 * @param string $method name of method calling us
-	 * @param $timeout Integer: timeout
-	 * @return Boolean
+	 * @param string $lockName Name of lock to aquire
+	 * @param string $method Name of method calling us
+	 * @param int $timeout
+	 * @return bool
 	 */
 	public function lock( $lockName, $method, $timeout = 5 ) {
 		return true;
@@ -3830,11 +4152,10 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Lock specific tables
 	 *
-	 * @param array $read of tables to lock for read access
-	 * @param array $write of tables to lock for write access
-	 * @param string $method name of caller
+	 * @param array $read Array of tables to lock for read access
+	 * @param array $write Array of tables to lock for write access
+	 * @param string $method Name of caller
 	 * @param bool $lowPriority Whether to indicate writes to be LOW PRIORITY
-	 *
 	 * @return bool
 	 */
 	public function lockTables( $read, $write, $method, $lowPriority = true ) {
@@ -3844,8 +4165,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Unlock specific tables
 	 *
-	 * @param string $method the caller
-	 *
+	 * @param string $method The caller
 	 * @return bool
 	 */
 	public function unlockTables( $method ) {
@@ -3854,8 +4174,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * Delete a table
-	 * @param $tableName string
-	 * @param $fName string
+	 * @param string $tableName
+	 * @param string $fName
 	 * @return bool|ResultWrapper
 	 * @since 1.18
 	 */
@@ -3867,6 +4187,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 		if ( $this->cascadingDeletes() ) {
 			$sql .= " CASCADE";
 		}
+
 		return $this->query( $sql, $fName );
 	}
 
@@ -3874,7 +4195,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Get search engine class. All subclasses of this need to implement this
 	 * if they wish to use searching.
 	 *
-	 * @return String
+	 * @return string
 	 */
 	public function getSearchEngine() {
 		return 'SearchEngineDummy';
@@ -3885,7 +4206,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * keyword for timestamps in PostgreSQL, and works with CHAR(14) as well
 	 * because "i" sorts after all numbers.
 	 *
-	 * @return String
+	 * @return string
 	 */
 	public function getInfinity() {
 		return 'infinity';
@@ -3894,8 +4215,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	/**
 	 * Encode an expiry time into the DBMS dependent format
 	 *
-	 * @param string $expiry timestamp for expiry, or the 'infinity' string
-	 * @return String
+	 * @param string $expiry Timestamp for expiry, or the 'infinity' string
+	 * @return string
 	 */
 	public function encodeExpiry( $expiry ) {
 		return ( $expiry == '' || $expiry == 'infinity' || $expiry == $this->getInfinity() )
@@ -3907,8 +4228,8 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 * Decode an expiry time into a DBMS independent format
 	 *
 	 * @param string $expiry DB timestamp field value for expiry
-	 * @param $format integer: TS_* constant, defaults to TS_MW
-	 * @return String
+	 * @param int $format TS_* constant, defaults to TS_MW
+	 * @return string
 	 */
 	public function decodeExpiry( $expiry, $format = TS_MW ) {
 		return ( $expiry == '' || $expiry == $this->getInfinity() )
@@ -3922,7 +4243,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 	 *
 	 * This is a MySQL-specific feature.
 	 *
-	 * @param $value Mixed: true for allow, false for deny, or "default" to
+	 * @param bool|string $value True for allow, false for deny, or "default" to
 	 *   restore the initial value
 	 */
 	public function setBigSelects( $value = true ) {
@@ -3931,6 +4252,7 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 
 	/**
 	 * @since 1.19
+	 * @return string
 	 */
 	public function __toString() {
 		return (string)$this->mConn;
@@ -3947,10 +4269,9 @@ abstract class DatabaseBase implements IDatabase, DatabaseType {
 			$callers = array();
 			foreach ( $this->mTrxIdleCallbacks as $callbackInfo ) {
 				$callers[] = $callbackInfo[1];
-
 			}
 			$callers = implode( ', ', $callers );
-			trigger_error( "DB transaction  callbacks still pending (from $callers)." );
+			trigger_error( "DB transaction callbacks still pending (from $callers)." );
 		}
 	}
 }
diff --git a/includes/db/DatabaseError.php b/includes/db/DatabaseError.php
index 0875695f..2dfec41d 100644
--- a/includes/db/DatabaseError.php
+++ b/includes/db/DatabaseError.php
@@ -26,22 +26,28 @@
  * @ingroup Database
  */
 class DBError extends MWException {
-
-	/**
-	 * @var DatabaseBase
-	 */
+	/** @var DatabaseBase */
 	public $db;
 
 	/**
 	 * Construct a database error
-	 * @param $db DatabaseBase object which threw the error
+	 * @param DatabaseBase $db Object which threw the error
 	 * @param string $error A simple error message to be used for debugging
 	 */
 	function __construct( DatabaseBase $db = null, $error ) {
 		$this->db = $db;
 		parent::__construct( $error );
 	}
+}
 
+/**
+ * Base class for the more common types of database errors. These are known to occur
+ * frequently, so we try to give friendly error messages for them.
+ *
+ * @ingroup Database
+ * @since 1.23
+ */
+class DBExpectedError extends DBError {
 	/**
 	 * @return string
 	 */
@@ -66,8 +72,7 @@ class DBError extends MWException {
 		$s = $this->getHTMLContent();
 
 		if ( $wgShowDBErrorBacktrace ) {
-			$s .= '<p>Backtrace:</p><p>' .
-				nl2br( htmlspecialchars( $this->getTraceAsString() ) ) . '</p>';
+			$s .= '<p>Backtrace:</p><pre>' . htmlspecialchars( $this->getTraceAsString() ) . '</pre>';
 		}
 
 		return $s;
@@ -84,16 +89,21 @@ class DBError extends MWException {
 	 * @return string
 	 */
 	protected function getHTMLContent() {
-		return '<p>' . nl2br( htmlspecialchars( $this->getMessage() ) ) . '</p>';
+		return '<p>' . nl2br( htmlspecialchars( $this->getTextContent() ) ) . '</p>';
 	}
 }
 
 /**
  * @ingroup Database
  */
-class DBConnectionError extends DBError {
+class DBConnectionError extends DBExpectedError {
+	/** @var string Error text */
 	public $error;
 
+	/**
+	 * @param DatabaseBase $db Object throwing the error
+	 * @param string $error Error text
+	 */
 	function __construct( DatabaseBase $db = null, $error = 'unknown error' ) {
 		$msg = 'DB connection error';
 
@@ -116,25 +126,24 @@ class DBConnectionError extends DBError {
 	}
 
 	/**
-	 * @param $key
-	 * @param $fallback
-	 * @return string
+	 * @param string $key
+	 * @param string $fallback Unescaped alternative error text in case the
+	 *   message cache cannot be used. Can contain parameters as in regular
+	 *   messages, that should be passed as additional parameters.
+	 * @return string Unprocessed plain error text with parameters replaced
 	 */
 	function msg( $key, $fallback /*[, params...] */ ) {
-		global $wgLang;
-
 		$args = array_slice( func_get_args(), 2 );
 
 		if ( $this->useMessageCache() ) {
-			$message = $wgLang->getMessage( $key );
+			return wfMessage( $key, $args )->useDatabase( false )->text();
 		} else {
-			$message = $fallback;
+			return wfMsgReplaceArgs( $fallback, $args );
 		}
-		return wfMsgReplaceArgs( $message, $args );
 	}
 
 	/**
-	 * @return boolean
+	 * @return bool
 	 */
 	function isLoggable() {
 		// Don't send to the exception log, already in dberror log
@@ -142,20 +151,19 @@ class DBConnectionError extends DBError {
 	}
 
 	/**
-	 * @return string
-	 */
-	function getPageTitle() {
-		return $this->msg( 'dberr-header', 'This wiki has a problem' );
-	}
-
-	/**
-	 * @return string
+	 * @return string Safe HTML
 	 */
 	function getHTML() {
 		global $wgShowDBErrorBacktrace, $wgShowHostnames, $wgShowSQLErrors;
 
-		$sorry = htmlspecialchars( $this->msg( 'dberr-problems', "Sorry!\nThis site is experiencing technical difficulties." ) );
-		$again = htmlspecialchars( $this->msg( 'dberr-again', 'Try waiting a few minutes and reloading.' ) );
+		$sorry = htmlspecialchars( $this->msg(
+			'dberr-problems',
+			'Sorry! This site is experiencing technical difficulties.'
+		) );
+		$again = htmlspecialchars( $this->msg(
+			'dberr-again',
+			'Try waiting a few minutes and reloading.'
+		) );
 
 		if ( $wgShowHostnames || $wgShowSQLErrors ) {
 			$info = str_replace(
@@ -163,23 +171,25 @@ class DBConnectionError extends DBError {
 				htmlspecialchars( $this->msg( 'dberr-info', '(Cannot contact the database server: $1)' ) )
 			);
 		} else {
-			$info = htmlspecialchars( $this->msg( 'dberr-info-hidden', '(Cannot contact the database server)' ) );
+			$info = htmlspecialchars( $this->msg(
+				'dberr-info-hidden',
+				'(Cannot contact the database server)'
+			) );
 		}
 
 		# No database access
 		MessageCache::singleton()->disable();
 
-		$text = "<h1>$sorry</h1><p>$again</p><p><small>$info</small></p>";
+		$html = "<h1>$sorry</h1><p>$again</p><p><small>$info</small></p>";
 
 		if ( $wgShowDBErrorBacktrace ) {
-			$text .= '<p>Backtrace:</p><p>' .
-				nl2br( htmlspecialchars( $this->getTraceAsString() ) ) . '</p>';
+			$html .= '<p>Backtrace:</p><pre>' . htmlspecialchars( $this->getTraceAsString() ) . '</pre>';
 		}
 
-		$text .= '<hr />';
-		$text .= $this->searchForm();
+		$html .= '<hr />';
+		$html .= $this->searchForm();
 
-		return $text;
+		return $html;
 	}
 
 	protected function getTextContent() {
@@ -192,25 +202,31 @@ class DBConnectionError extends DBError {
 		}
 	}
 
+	/**
+	 * Output the exception report using HTML.
+	 *
+	 * @return void
+	 */
 	public function reportHTML() {
 		global $wgUseFileCache;
 
-		# Check whether we can serve a file-cached copy of the page with the error underneath
+		// Check whether we can serve a file-cached copy of the page with the error underneath
 		if ( $wgUseFileCache ) {
 			try {
 				$cache = $this->fileCachedPage();
-				# Cached version on file system?
+				// Cached version on file system?
 				if ( $cache !== null ) {
-					# Hack: extend the body for error messages
+					// Hack: extend the body for error messages
 					$cache = str_replace( array( '</html>', '</body>' ), '', $cache );
-					# Add cache notice...
-					$cache .= '<div style="color:red;font-size:150%;font-weight:bold;">' .
+					// Add cache notice...
+					$cache .= '<div style="border:1px solid #ffd0d0;padding:1em;">' .
 						htmlspecialchars( $this->msg( 'dberr-cachederror',
-							'This is a cached copy of the requested page, and may not be up to date. ' ) ) .
+							'This is a cached copy of the requested page, and may not be up to date.' ) ) .
 						'</div>';
 
-					# Output cached page with notices on bottom and re-close body
+					// Output cached page with notices on bottom and re-close body
 					echo "{$cache}<hr />{$this->getHTML()}</body></html>";
+
 					return;
 				}
 			} catch ( MWException $e ) {
@@ -218,7 +234,7 @@ class DBConnectionError extends DBError {
 			}
 		}
 
-		# We can't, cough and die in the usual fashion
+		// We can't, cough and die in the usual fashion
 		parent::reportHTML();
 	}
 
@@ -228,8 +244,14 @@ class DBConnectionError extends DBError {
 	function searchForm() {
 		global $wgSitename, $wgCanonicalServer, $wgRequest;
 
-		$usegoogle = htmlspecialchars( $this->msg( 'dberr-usegoogle', 'You can try searching via Google in the meantime.' ) );
-		$outofdate = htmlspecialchars( $this->msg( 'dberr-outofdate', 'Note that their indexes of our content may be out of date.' ) );
+		$usegoogle = htmlspecialchars( $this->msg(
+			'dberr-usegoogle',
+			'You can try searching via Google in the meantime.'
+		) );
+		$outofdate = htmlspecialchars( $this->msg(
+			'dberr-outofdate',
+			'Note that their indexes of our content may be out of date.'
+		) );
 		$googlesearch = htmlspecialchars( $this->msg( 'searchbutton', 'Search' ) );
 
 		$search = htmlspecialchars( $wgRequest->getVal( 'search' ) );
@@ -239,8 +261,8 @@ class DBConnectionError extends DBError {
 
 		$trygoogle = <<<EOT
 <div style="margin: 1.5em">$usegoogle<br />
-<small>$outofdate</small></div>
-<!-- SiteSearch Google -->
+<small>$outofdate</small>
+</div>
 <form method="get" action="//www.google.com/search" id="googlesearch">
 	<input type="hidden" name="domains" value="$server" />
 	<input type="hidden" name="num" value="50" />
@@ -249,13 +271,13 @@ class DBConnectionError extends DBError {
 
 	<input type="text" name="q" size="31" maxlength="255" value="$search" />
 	<input type="submit" name="btnG" value="$googlesearch" />
-  <div>
-	<input type="radio" name="sitesearch" id="gwiki" value="$server" checked="checked" /><label for="gwiki">$sitename</label>
-	<input type="radio" name="sitesearch" id="gWWW" value="" /><label for="gWWW">WWW</label>
-  </div>
+	<p>
+		<label><input type="radio" name="sitesearch" value="$server" checked="checked" />$sitename</label>
+		<label><input type="radio" name="sitesearch" value="" />WWW</label>
+	</p>
 </form>
-<!-- SiteSearch Google -->
 EOT;
+
 		return $trygoogle;
 	}
 
@@ -263,26 +285,28 @@ EOT;
 	 * @return string
 	 */
 	private function fileCachedPage() {
-		global $wgTitle, $wgOut, $wgRequest;
+		$context = RequestContext::getMain();
 
-		if ( $wgOut->isDisabled() ) {
-			return ''; // Done already?
+		if ( $context->getOutput()->isDisabled() ) {
+			// Done already?
+			return '';
 		}
 
-		if ( $wgTitle ) { // use $wgTitle if we managed to set it
-			$t = $wgTitle->getPrefixedDBkey();
+		if ( $context->getTitle() ) {
+			// Use the main context's title if we managed to set it
+			$t = $context->getTitle()->getPrefixedDBkey();
 		} else {
-			# Fallback to the raw title URL param. We can't use the Title
-			# class is it may hit the interwiki table and give a DB error.
-			# We may get a cache miss due to not sanitizing the title though.
-			$t = str_replace( ' ', '_', $wgRequest->getVal( 'title' ) );
+			// Fallback to the raw title URL param. We can't use the Title
+			// class is it may hit the interwiki table and give a DB error.
+			// We may get a cache miss due to not sanitizing the title though.
+			$t = str_replace( ' ', '_', $context->getRequest()->getVal( 'title' ) );
 			if ( $t == '' ) { // fallback to main page
 				$t = Title::newFromText(
 					$this->msg( 'mainpage', 'Main Page' ) )->getPrefixedDBkey();
 			}
 		}
 
-		$cache = HTMLFileCache::newFromTitle( $t, 'view' );
+		$cache = new HTMLFileCache( $t, 'view' );
 		if ( $cache->isCached() ) {
 			return $cache->fetchText();
 		} else {
@@ -294,18 +318,20 @@ EOT;
 /**
  * @ingroup Database
  */
-class DBQueryError extends DBError {
+class DBQueryError extends DBExpectedError {
 	public $error, $errno, $sql, $fname;
 
 	/**
-	 * @param $db DatabaseBase
-	 * @param $error string
-	 * @param $errno int|string
-	 * @param $sql string
-	 * @param $fname string
+	 * @param DatabaseBase $db
+	 * @param string $error
+	 * @param int|string $errno
+	 * @param string $sql
+	 * @param string $fname
 	 */
 	function __construct( DatabaseBase $db, $error, $errno, $sql, $fname ) {
-		$message = "A database error has occurred. Did you forget to run maintenance/update.php after upgrading?  See: https://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script\n" .
+		$message = "A database error has occurred. Did you forget to run " .
+			"maintenance/update.php after upgrading?  See: " .
+			"https://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script\n" .
 			"Query: $sql\n" .
 			"Function: $fname\n" .
 			"Error: $errno $error\n";
@@ -318,14 +344,6 @@ class DBQueryError extends DBError {
 	}
 
 	/**
-	 * @return boolean
-	 */
-	function isLoggable() {
-		// Don't send to the exception log, already in dberror log
-		return false;
-	}
-
-	/**
 	 * @return string
 	 */
 	function getPageTitle() {
@@ -380,7 +398,7 @@ class DBQueryError extends DBError {
 	 * sites using this option probably don't care much about "security by obscurity". Of course,
 	 * if $wgShowSQLErrors is true, the SQL query *is* shown.
 	 *
-	 * @return array: Keys are message keys; values are arrays of arguments for Html::element().
+	 * @return array Keys are message keys; values are arrays of arguments for Html::element().
 	 *   Array will be empty if users are not allowed to see any of these details at all.
 	 */
 	protected function getTechnicalDetails() {
@@ -405,7 +423,7 @@ class DBQueryError extends DBError {
 
 	/**
 	 * @param string $key Message key
-	 * @return string: English message text
+	 * @return string English message text
 	 */
 	private function getFallbackMessage( $key ) {
 		$messages = array(
@@ -416,12 +434,13 @@ This may indicate a bug in the software.',
 			'databaseerror-function' => 'Function: $1',
 			'databaseerror-error' => 'Error: $1',
 		);
+
 		return $messages[$key];
 	}
-
 }
 
 /**
  * @ingroup Database
  */
-class DBUnexpectedError extends DBError {}
+class DBUnexpectedError extends DBError {
+}
diff --git a/includes/db/DatabaseMssql.php b/includes/db/DatabaseMssql.php
index 37f5372e..af3cc72d 100644
--- a/includes/db/DatabaseMssql.php
+++ b/includes/db/DatabaseMssql.php
@@ -22,47 +22,54 @@
  * @author Joel Penner <a-joelpe at microsoft dot com>
  * @author Chris Pucci <a-cpucci at microsoft dot com>
  * @author Ryan Biesemeyer <v-ryanbi at microsoft dot com>
+ * @author Ryan Schmidt <skizzerz at gmail dot com>
  */
 
 /**
  * @ingroup Database
  */
 class DatabaseMssql extends DatabaseBase {
-	var $mInsertId = null;
-	var $mLastResult = null;
-	var $mAffectedRows = null;
-
-	var $mPort;
-
-	function cascadingDeletes() {
+	protected $mInsertId = null;
+	protected $mLastResult = null;
+	protected $mAffectedRows = null;
+	protected $mSubqueryId = 0;
+	protected $mScrollableCursor = true;
+	protected $mPrepareStatements = true;
+	protected $mBinaryColumnCache = null;
+	protected $mBitColumnCache = null;
+	protected $mIgnoreDupKeyErrors = false;
+
+	protected $mPort;
+
+	public function cascadingDeletes() {
 		return true;
 	}
 
-	function cleanupTriggers() {
-		return true;
+	public function cleanupTriggers() {
+		return false;
 	}
 
-	function strictIPs() {
-		return true;
+	public function strictIPs() {
+		return false;
 	}
 
-	function realTimestamps() {
-		return true;
+	public function realTimestamps() {
+		return false;
 	}
 
-	function implicitGroupby() {
+	public function implicitGroupby() {
 		return false;
 	}
 
-	function implicitOrderby() {
+	public function implicitOrderby() {
 		return false;
 	}
 
-	function functionalIndexes() {
+	public function functionalIndexes() {
 		return true;
 	}
 
-	function unionSupportsOrderAndLimit() {
+	public function unionSupportsOrderAndLimit() {
 		return false;
 	}
 
@@ -75,16 +82,21 @@ class DatabaseMssql extends DatabaseBase {
 	 * @throws DBConnectionError
 	 * @return bool|DatabaseBase|null
 	 */
-	function open( $server, $user, $password, $dbName ) {
+	public function open( $server, $user, $password, $dbName ) {
 		# Test for driver support, to avoid suppressed fatal error
 		if ( !function_exists( 'sqlsrv_connect' ) ) {
-			throw new DBConnectionError( $this, "MS Sql Server Native (sqlsrv) functions missing. You can download the driver from: http://go.microsoft.com/fwlink/?LinkId=123470\n" );
+			throw new DBConnectionError(
+				$this,
+				"Microsoft SQL Server Native (sqlsrv) functions missing.
+				You can download the driver from: http://go.microsoft.com/fwlink/?LinkId=123470\n"
+			);
 		}
 
-		global $wgDBport;
+		global $wgDBport, $wgDBWindowsAuthentication;
 
-		if ( !strlen( $user ) ) { # e.g. the class is being loaded
-			return;
+		# e.g. the class is being loaded
+		if ( !strlen( $user ) ) {
+			return null;
 		}
 
 		$this->close();
@@ -100,35 +112,23 @@ class DatabaseMssql extends DatabaseBase {
 			$connectionInfo['Database'] = $dbName;
 		}
 
-		// Start NT Auth Hack
-		// Quick and dirty work around to provide NT Auth designation support.
-		// Current solution requires installer to know to input 'ntauth' for both username and password
-		// to trigger connection via NT Auth. - ugly, ugly, ugly
-		// TO-DO: Make this better and add NT Auth choice to MW installer when SQL Server option is chosen.
-		$ntAuthUserTest = strtolower( $user );
-		$ntAuthPassTest = strtolower( $password );
-
 		// Decide which auth scenerio to use
-		if ( $ntAuthPassTest == 'ntauth' && $ntAuthUserTest == 'ntauth' ) {
-			// Don't add credentials to $connectionInfo
-		} else {
+		// if we are using Windows auth, don't add credentials to $connectionInfo
+		if ( !$wgDBWindowsAuthentication ) {
 			$connectionInfo['UID'] = $user;
 			$connectionInfo['PWD'] = $password;
 		}
-		// End NT Auth Hack
 
 		wfSuppressWarnings();
 		$this->mConn = sqlsrv_connect( $server, $connectionInfo );
 		wfRestoreWarnings();
 
 		if ( $this->mConn === false ) {
-			wfDebug( "DB connection error\n" );
-			wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
-			wfDebug( $this->lastError() . "\n" );
-			return false;
+			throw new DBConnectionError( $this, $this->lastError() );
 		}
 
 		$this->mOpened = true;
+
 		return $this->mConn;
 	}
 
@@ -141,14 +141,39 @@ class DatabaseMssql extends DatabaseBase {
 		return sqlsrv_close( $this->mConn );
 	}
 
+	/**
+	 * @param bool|MssqlResultWrapper|resource $result
+	 * @return bool|MssqlResultWrapper
+	 */
+	public function resultObject( $result ) {
+		if ( empty( $result ) ) {
+			return false;
+		} elseif ( $result instanceof MssqlResultWrapper ) {
+			return $result;
+		} elseif ( $result === true ) {
+			// Successful write query
+			return $result;
+		} else {
+			return new MssqlResultWrapper( $this, $result );
+		}
+	}
+
+	/**
+	 * @param string $sql
+	 * @return bool|MssqlResult
+	 * @throws DBUnexpectedError
+	 */
 	protected function doQuery( $sql ) {
-		wfDebug( "SQL: [$sql]\n" );
+		if ( $this->debug() ) {
+			wfDebug( "SQL: [$sql]\n" );
+		}
 		$this->offset = 0;
 
-		// several extensions seem to think that all databases support limits via LIMIT N after the WHERE clause
-		// well, MSSQL uses SELECT TOP N, so to catch any of those extensions we'll do a quick check for a LIMIT
-		// clause and pass $sql through $this->LimitToTopN() which parses the limit clause and passes the result to
-		// $this->limitResult();
+		// several extensions seem to think that all databases support limits
+		// via LIMIT N after the WHERE clause well, MSSQL uses SELECT TOP N,
+		// so to catch any of those extensions we'll do a quick check for a
+		// LIMIT clause and pass $sql through $this->LimitToTopN() which parses
+		// the limit clause and passes the result to $this->limitResult();
 		if ( preg_match( '/\bLIMIT\s*/i', $sql ) ) {
 			// massage LIMIT -> TopN
 			$sql = $this->LimitToTopN( $sql );
@@ -161,149 +186,235 @@ class DatabaseMssql extends DatabaseBase {
 		}
 
 		// perform query
-		$stmt = sqlsrv_query( $this->mConn, $sql );
-		if ( $stmt == false ) {
-			$message = "A database error has occurred. Did you forget to run maintenance/update.php after upgrading?  See: http://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script\n" .
-				"Query: " . htmlentities( $sql ) . "\n" .
-				"Function: " . __METHOD__ . "\n";
-			// process each error (our driver will give us an array of errors unlike other providers)
-			foreach ( sqlsrv_errors() as $error ) {
-				$message .= $message . "ERROR[" . $error['code'] . "] " . $error['message'] . "\n";
-			}
 
-			throw new DBUnexpectedError( $this, $message );
+		// SQLSRV_CURSOR_STATIC is slower than SQLSRV_CURSOR_CLIENT_BUFFERED (one of the two is
+		// needed if we want to be able to seek around the result set), however CLIENT_BUFFERED
+		// has a bug in the sqlsrv driver where wchar_t types (such as nvarchar) that are empty
+		// strings make php throw a fatal error "Severe error translating Unicode"
+		if ( $this->mScrollableCursor ) {
+			$scrollArr = array( 'Scrollable' => SQLSRV_CURSOR_STATIC );
+		} else {
+			$scrollArr = array();
 		}
-		// remember number of rows affected
-		$this->mAffectedRows = sqlsrv_rows_affected( $stmt );
 
-		// if it is a SELECT statement, or an insert with a request to output something we want to return a row.
-		if ( ( preg_match( '#\bSELECT\s#i', $sql ) ) ||
-			( preg_match( '#\bINSERT\s#i', $sql ) && preg_match( '#\bOUTPUT\s+INSERTED\b#i', $sql ) ) ) {
-			// this is essentially a rowset, but Mediawiki calls these 'result'
-			// the rowset owns freeing the statement
-			$res = new MssqlResult( $stmt );
+		if ( $this->mPrepareStatements ) {
+			// we do prepare + execute so we can get its field metadata for later usage if desired
+			$stmt = sqlsrv_prepare( $this->mConn, $sql, array(), $scrollArr );
+			$success = sqlsrv_execute( $stmt );
 		} else {
-			// otherwise we simply return it was successful, failure throws an exception
-			$res = true;
+			$stmt = sqlsrv_query( $this->mConn, $sql, array(), $scrollArr );
+			$success = (bool)$stmt;
 		}
-		return $res;
-	}
 
-	function freeResult( $res ) {
-		if ( $res instanceof ResultWrapper ) {
-			$res = $res->result;
+		if ( $this->mIgnoreDupKeyErrors ) {
+			// ignore duplicate key errors, but nothing else
+			// this emulates INSERT IGNORE in MySQL
+			if ( $success === false ) {
+				$errors = sqlsrv_errors( SQLSRV_ERR_ERRORS );
+				$success = true;
+
+				foreach ( $errors as $err ) {
+					if ( $err['SQLSTATE'] == '23000' && $err['code'] == '2601' ) {
+						continue; // duplicate key error caused by unique index
+					} elseif ( $err['SQLSTATE'] == '23000' && $err['code'] == '2627' ) {
+						continue; // duplicate key error caused by primary key
+					} elseif ( $err['SQLSTATE'] == '01000' && $err['code'] == '3621' ) {
+						continue; // generic "the statement has been terminated" error
+					}
+
+					$success = false; // getting here means we got an error we weren't expecting
+					break;
+				}
+
+				if ( $success ) {
+					$this->mAffectedRows = 0;
+					return $stmt;
+				}
+			}
+		}
+
+		if ( $success === false ) {
+			return false;
 		}
-		$res->free();
+		// remember number of rows affected
+		$this->mAffectedRows = sqlsrv_rows_affected( $stmt );
+
+		return $stmt;
 	}
 
-	function fetchObject( $res ) {
+	public function freeResult( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
-		$row = $res->fetch( 'OBJECT' );
-		return $row;
+
+		sqlsrv_free_stmt( $res );
 	}
 
-	function getErrors() {
-		$strRet = '';
-		$retErrors = sqlsrv_errors( SQLSRV_ERR_ALL );
-		if ( $retErrors != null ) {
-			foreach ( $retErrors as $arrError ) {
-				$strRet .= "SQLState: " . $arrError['SQLSTATE'] . "\n";
-				$strRet .= "Error Code: " . $arrError['code'] . "\n";
-				$strRet .= "Message: " . $arrError['message'] . "\n";
-			}
-		} else {
-			$strRet = "No errors found";
-		}
-		return $strRet;
+	/**
+	 * @param MssqlResultWrapper $res
+	 * @return stdClass
+	 */
+	public function fetchObject( $res ) {
+		// $res is expected to be an instance of MssqlResultWrapper here
+		return $res->fetchObject();
 	}
 
-	function fetchRow( $res ) {
-		if ( $res instanceof ResultWrapper ) {
-			$res = $res->result;
-		}
-		$row = $res->fetch( SQLSRV_FETCH_BOTH );
-		return $row;
+	/**
+	 * @param MssqlResultWrapper $res
+	 * @return array
+	 */
+	public function fetchRow( $res ) {
+		return $res->fetchRow();
 	}
 
-	function numRows( $res ) {
+	/**
+	 * @param mixed $res
+	 * @return int
+	 */
+	public function numRows( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
-		return ( $res ) ? $res->numrows() : 0;
+
+		return sqlsrv_num_rows( $res );
 	}
 
-	function numFields( $res ) {
+	/**
+	 * @param mixed $res
+	 * @return int
+	 */
+	public function numFields( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
-		return ( $res ) ? $res->numfields() : 0;
+
+		return sqlsrv_num_fields( $res );
 	}
 
-	function fieldName( $res, $n ) {
+	/**
+	 * @param mixed $res
+	 * @param int $n
+	 * @return int
+	 */
+	public function fieldName( $res, $n ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
-		return ( $res ) ? $res->fieldname( $n ) : 0;
+
+		$metadata = sqlsrv_field_metadata( $res );
+		return $metadata[$n]['Name'];
 	}
 
 	/**
 	 * This must be called after nextSequenceVal
-	 * @return null
+	 * @return int|null
 	 */
-	function insertId() {
+	public function insertId() {
 		return $this->mInsertId;
 	}
 
-	function dataSeek( $res, $row ) {
-		if ( $res instanceof ResultWrapper ) {
-			$res = $res->result;
-		}
-		return ( $res ) ? $res->seek( $row ) : false;
+	/**
+	 * @param MssqlResultWrapper $res
+	 * @param int $row
+	 * @return bool
+	 */
+	public function dataSeek( $res, $row ) {
+		return $res->seek( $row );
 	}
 
-	function lastError() {
-		if ( $this->mConn ) {
-			return $this->getErrors();
+	/**
+	 * @return string
+	 */
+	public function lastError() {
+		$strRet = '';
+		$retErrors = sqlsrv_errors( SQLSRV_ERR_ALL );
+		if ( $retErrors != null ) {
+			foreach ( $retErrors as $arrError ) {
+				$strRet .= $this->formatError( $arrError ) . "\n";
+			}
 		} else {
-			return "No database connection";
+			$strRet = "No errors found";
 		}
+
+		return $strRet;
+	}
+
+	/**
+	 * @param array $err
+	 * @return string
+	 */
+	private function formatError( $err ) {
+		return '[SQLSTATE ' . $err['SQLSTATE'] . '][Error Code ' . $err['code'] . ']' . $err['message'];
 	}
 
-	function lastErrno() {
+	/**
+	 * @return string
+	 */
+	public function lastErrno() {
 		$err = sqlsrv_errors( SQLSRV_ERR_ALL );
-		if ( $err[0] ) {
+		if ( $err !== null && isset( $err[0] ) ) {
 			return $err[0]['code'];
 		} else {
 			return 0;
 		}
 	}
 
-	function affectedRows() {
+	/**
+	 * @return int
+	 */
+	public function affectedRows() {
 		return $this->mAffectedRows;
 	}
 
 	/**
 	 * SELECT wrapper
 	 *
-	 * @param $table   Mixed: array or string, table name(s) (prefix auto-added)
-	 * @param $vars    Mixed: array or string, field name(s) to be retrieved
-	 * @param $conds   Mixed: array or string, condition(s) for WHERE
-	 * @param $fname   String: calling function name (use __METHOD__) for logs/profiling
-	 * @param array $options associative array of options (e.g. array('GROUP BY' => 'page_title')),
-	 *                 see Database::makeSelectOptions code for list of supported stuff
-	 * @param $join_conds Array: Associative array of table join conditions (optional)
-	 *						   (e.g. array( 'page' => array('LEFT JOIN','page_latest=rev_id') )
-	 * @return Mixed: database result resource (feed to Database::fetchObject or whatever), or false on failure
+	 * @param mixed $table Array or string, table name(s) (prefix auto-added)
+	 * @param mixed $vars Array or string, field name(s) to be retrieved
+	 * @param mixed $conds Array or string, condition(s) for WHERE
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
+	 * @param array $options Associative array of options (e.g.
+	 *   array('GROUP BY' => 'page_title')), see Database::makeSelectOptions
+	 *   code for list of supported stuff
+	 * @param array $join_conds Associative array of table join conditions
+	 *   (optional) (e.g. array( 'page' => array('LEFT JOIN','page_latest=rev_id') )
+	 * @return mixed Database result resource (feed to Database::fetchObject
+	 *   or whatever), or false on failure
 	 */
-	function select( $table, $vars, $conds = '', $fname = __METHOD__, $options = array(), $join_conds = array() )
-	{
+	public function select( $table, $vars, $conds = '', $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	) {
 		$sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
 		if ( isset( $options['EXPLAIN'] ) ) {
-			sqlsrv_query( $this->mConn, "SET SHOWPLAN_ALL ON;" );
-			$ret = $this->query( $sql, $fname );
-			sqlsrv_query( $this->mConn, "SET SHOWPLAN_ALL OFF;" );
+			try {
+				$this->mScrollableCursor = false;
+				$this->mPrepareStatements = false;
+				$this->query( "SET SHOWPLAN_ALL ON" );
+				$ret = $this->query( $sql, $fname );
+				$this->query( "SET SHOWPLAN_ALL OFF" );
+			} catch ( DBQueryError $dqe ) {
+				if ( isset( $options['FOR COUNT'] ) ) {
+					// likely don't have privs for SHOWPLAN, so run a select count instead
+					$this->query( "SET SHOWPLAN_ALL OFF" );
+					unset( $options['EXPLAIN'] );
+					$ret = $this->select(
+						$table,
+						'COUNT(*) AS EstimateRows',
+						$conds,
+						$fname,
+						$options,
+						$join_conds
+					);
+				} else {
+					// someone actually wanted the query plan instead of an est row count
+					// let them know of the error
+					$this->mScrollableCursor = true;
+					$this->mPrepareStatements = true;
+					throw $dqe;
+				}
+			}
+			$this->mScrollableCursor = true;
+			$this->mPrepareStatements = true;
 			return $ret;
 		}
 		return $this->query( $sql, $fname );
@@ -312,21 +423,70 @@ class DatabaseMssql extends DatabaseBase {
 	/**
 	 * SELECT wrapper
 	 *
-	 * @param $table   Mixed:  Array or string, table name(s) (prefix auto-added)
-	 * @param $vars    Mixed:  Array or string, field name(s) to be retrieved
-	 * @param $conds   Mixed:  Array or string, condition(s) for WHERE
-	 * @param $fname   String: Calling function name (use __METHOD__) for logs/profiling
-	 * @param array $options  Associative array of options (e.g. array('GROUP BY' => 'page_title')),
-	 *                 see Database::makeSelectOptions code for list of supported stuff
-	 * @param $join_conds Array: Associative array of table join conditions (optional)
-	 *                    (e.g. array( 'page' => array('LEFT JOIN','page_latest=rev_id') )
-	 * @return string, the SQL text
+	 * @param mixed $table Array or string, table name(s) (prefix auto-added)
+	 * @param mixed $vars Array or string, field name(s) to be retrieved
+	 * @param mixed $conds Array or string, condition(s) for WHERE
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
+	 * @param array $options Associative array of options (e.g. array('GROUP BY' => 'page_title')),
+	 *   see Database::makeSelectOptions code for list of supported stuff
+	 * @param array $join_conds Associative array of table join conditions (optional)
+	 *    (e.g. array( 'page' => array('LEFT JOIN','page_latest=rev_id') )
+	 * @return string The SQL text
 	 */
-	function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__, $options = array(), $join_conds = array() ) {
+	public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	) {
 		if ( isset( $options['EXPLAIN'] ) ) {
 			unset( $options['EXPLAIN'] );
 		}
-		return parent::selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
+
+		$sql = parent::selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
+
+		// try to rewrite aggregations of bit columns (currently MAX and MIN)
+		if ( strpos( $sql, 'MAX(' ) !== false || strpos( $sql, 'MIN(' ) !== false ) {
+			$bitColumns = array();
+			if ( is_array( $table ) ) {
+				foreach ( $table as $t ) {
+					$bitColumns += $this->getBitColumns( $this->tableName( $t ) );
+				}
+			} else {
+				$bitColumns = $this->getBitColumns( $this->tableName( $table ) );
+			}
+
+			foreach ( $bitColumns as $col => $info ) {
+				$replace = array(
+					"MAX({$col})" => "MAX(CAST({$col} AS tinyint))",
+					"MIN({$col})" => "MIN(CAST({$col} AS tinyint))",
+				);
+				$sql = str_replace( array_keys( $replace ), array_values( $replace ), $sql );
+			}
+		}
+
+		return $sql;
+	}
+
+	public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
+		$fname = __METHOD__
+	) {
+		$this->mScrollableCursor = false;
+		try {
+			parent::deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname );
+		} catch ( Exception $e ) {
+			$this->mScrollableCursor = true;
+			throw $e;
+		}
+		$this->mScrollableCursor = true;
+	}
+
+	public function delete( $table, $conds, $fname = __METHOD__ ) {
+		$this->mScrollableCursor = false;
+		try {
+			parent::delete( $table, $conds, $fname );
+		} catch ( Exception $e ) {
+			$this->mScrollableCursor = true;
+			throw $e;
+		}
+		$this->mScrollableCursor = true;
 	}
 
 	/**
@@ -335,30 +495,45 @@ class DatabaseMssql extends DatabaseBase {
 	 * This is not necessarily an accurate estimate, so use sparingly
 	 * Returns -1 if count cannot be found
 	 * Takes same arguments as Database::select()
+	 * @param string $table
+	 * @param string $vars
+	 * @param string $conds
+	 * @param string $fname
+	 * @param array $options
 	 * @return int
 	 */
-	function estimateRowCount( $table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array() ) {
-		$options['EXPLAIN'] = true;// http://msdn2.microsoft.com/en-us/library/aa259203.aspx
+	public function estimateRowCount( $table, $vars = '*', $conds = '',
+		$fname = __METHOD__, $options = array()
+	) {
+		// http://msdn2.microsoft.com/en-us/library/aa259203.aspx
+		$options['EXPLAIN'] = true;
+		$options['FOR COUNT'] = true;
 		$res = $this->select( $table, $vars, $conds, $fname, $options );
 
 		$rows = -1;
 		if ( $res ) {
 			$row = $this->fetchRow( $res );
+
 			if ( isset( $row['EstimateRows'] ) ) {
 				$rows = $row['EstimateRows'];
 			}
 		}
+
 		return $rows;
 	}
 
 	/**
 	 * Returns information about an index
 	 * If errors are explicitly ignored, returns NULL on failure
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return array|bool|null
 	 */
-	function indexInfo( $table, $index, $fname = __METHOD__ ) {
-		# This does not return the same info as MYSQL would, but that's OK because MediaWiki never uses the
-		# returned value except to check for the existance of indexes.
+	public function indexInfo( $table, $index, $fname = __METHOD__ ) {
+		# This does not return the same info as MYSQL would, but that's OK
+		# because MediaWiki never uses the returned value except to check for
+		# the existance of indexes.
 		$sql = "sp_helpindex '" . $table . "'";
 		$res = $this->query( $sql, $fname );
 		if ( !$res ) {
@@ -383,6 +558,7 @@ class DatabaseMssql extends DatabaseBase {
 				}
 			}
 		}
+
 		return empty( $result ) ? false : $result;
 	}
 
@@ -401,7 +577,7 @@ class DatabaseMssql extends DatabaseBase {
 	 * @throws DBQueryError
 	 * @return bool
 	 */
-	function insert( $table, $arrToInsert, $fname = __METHOD__, $options = array() ) {
+	public function insert( $table, $arrToInsert, $fname = __METHOD__, $options = array() ) {
 		# No rows to insert, easy just return now
 		if ( !count( $arrToInsert ) ) {
 			return true;
@@ -413,24 +589,39 @@ class DatabaseMssql extends DatabaseBase {
 
 		$table = $this->tableName( $table );
 
-		if ( !( isset( $arrToInsert[0] ) && is_array( $arrToInsert[0] ) ) ) {// Not multi row
-			$arrToInsert = array( 0 => $arrToInsert );// make everything multi row compatible
+		if ( !( isset( $arrToInsert[0] ) && is_array( $arrToInsert[0] ) ) ) { // Not multi row
+			$arrToInsert = array( 0 => $arrToInsert ); // make everything multi row compatible
 		}
 
-		$allOk = true;
-
 		// We know the table we're inserting into, get its identity column
 		$identity = null;
-		$tableRaw = preg_replace( '#\[([^\]]*)\]#', '$1', $table ); // strip matching square brackets from table name
-		$res = $this->doQuery( "SELECT NAME AS idColumn FROM SYS.IDENTITY_COLUMNS WHERE OBJECT_NAME(OBJECT_ID)='{$tableRaw}'" );
-		if ( $res && $res->numrows() ) {
+		// strip matching square brackets and the db/schema from table name
+		$tableRawArr = explode( '.', preg_replace( '#\[([^\]]*)\]#', '$1', $table ) );
+		$tableRaw = array_pop( $tableRawArr );
+		$res = $this->doQuery(
+			"SELECT NAME AS idColumn FROM SYS.IDENTITY_COLUMNS " .
+				"WHERE OBJECT_NAME(OBJECT_ID)='{$tableRaw}'"
+		);
+		if ( $res && sqlsrv_has_rows( $res ) ) {
 			// There is an identity for this table.
-			$identity = array_pop( $res->fetch( SQLSRV_FETCH_ASSOC ) );
+			$identityArr = sqlsrv_fetch_array( $res, SQLSRV_FETCH_ASSOC );
+			$identity = array_pop( $identityArr );
+		}
+		sqlsrv_free_stmt( $res );
+
+		// Determine binary/varbinary fields so we can encode data as a hex string like 0xABCDEF
+		$binaryColumns = $this->getBinaryColumns( $table );
+
+		// INSERT IGNORE is not supported by SQL Server
+		// remove IGNORE from options list and set ignore flag to true
+		if ( in_array( 'IGNORE', $options ) ) {
+			$options = array_diff( $options, array( 'IGNORE' ) );
+			$this->mIgnoreDupKeyErrors = true;
 		}
-		unset( $res );
 
 		foreach ( $arrToInsert as $a ) {
-			// start out with empty identity column, this is so we can return it as a result of the insert logic
+			// start out with empty identity column, this is so we can return
+			// it as a result of the insert logic
 			$sqlPre = '';
 			$sqlPost = '';
 			$identityClause = '';
@@ -441,152 +632,246 @@ class DatabaseMssql extends DatabaseBase {
 				foreach ( $a as $k => $v ) {
 					if ( $k == $identity ) {
 						if ( !is_null( $v ) ) {
-							// there is a value being passed to us, we need to turn on and off inserted identity
+							// there is a value being passed to us,
+							// we need to turn on and off inserted identity
 							$sqlPre = "SET IDENTITY_INSERT $table ON;";
 							$sqlPost = ";SET IDENTITY_INSERT $table OFF;";
-
 						} else {
-							// we can't insert NULL into an identity column, so remove the column from the insert.
+							// we can't insert NULL into an identity column,
+							// so remove the column from the insert.
 							unset( $a[$k] );
 						}
 					}
 				}
-				$identityClause = "OUTPUT INSERTED.$identity "; // we want to output an identity column as result
-			}
-
-			$keys = array_keys( $a );
 
-			// INSERT IGNORE is not supported by SQL Server
-			// remove IGNORE from options list and set ignore flag to true
-			$ignoreClause = false;
-			foreach ( $options as $k => $v ) {
-				if ( strtoupper( $v ) == "IGNORE" ) {
-					unset( $options[$k] );
-					$ignoreClause = true;
-				}
+				// we want to output an identity column as result
+				$identityClause = "OUTPUT INSERTED.$identity ";
 			}
 
-			// translate MySQL INSERT IGNORE to something SQL Server can use
-			// example:
-			// MySQL: INSERT IGNORE INTO user_groups (ug_user,ug_group) VALUES ('1','sysop')
-			// MSSQL: IF NOT EXISTS (SELECT * FROM user_groups WHERE ug_user = '1') INSERT INTO user_groups (ug_user,ug_group) VALUES ('1','sysop')
-			if ( $ignoreClause ) {
-				$prival = $a[$keys[0]];
-				$sqlPre .= "IF NOT EXISTS (SELECT * FROM $table WHERE $keys[0] = '$prival')";
-			}
+			$keys = array_keys( $a );
 
 			// Build the actual query
 			$sql = $sqlPre . 'INSERT ' . implode( ' ', $options ) .
 				" INTO $table (" . implode( ',', $keys ) . ") $identityClause VALUES (";
 
 			$first = true;
-			foreach ( $a as $value ) {
+			foreach ( $a as $key => $value ) {
+				if ( isset( $binaryColumns[$key] ) ) {
+					$value = new MssqlBlob( $value );
+				}
 				if ( $first ) {
 					$first = false;
 				} else {
 					$sql .= ',';
 				}
-				if ( is_string( $value ) ) {
-					$sql .= $this->addQuotes( $value );
-				} elseif ( is_null( $value ) ) {
+				if ( is_null( $value ) ) {
 					$sql .= 'null';
 				} elseif ( is_array( $value ) || is_object( $value ) ) {
-					if ( is_object( $value ) && strtolower( get_class( $value ) ) == 'blob' ) {
+					if ( is_object( $value ) && $value instanceof Blob ) {
 						$sql .= $this->addQuotes( $value );
 					} else {
 						$sql .= $this->addQuotes( serialize( $value ) );
 					}
 				} else {
-					$sql .= $value;
+					$sql .= $this->addQuotes( $value );
 				}
 			}
 			$sql .= ')' . $sqlPost;
 
 			// Run the query
-			$ret = sqlsrv_query( $this->mConn, $sql );
-
-			if ( $ret === false ) {
-				throw new DBQueryError( $this, $this->getErrors(), $this->lastErrno(), $sql, $fname );
-			} elseif ( $ret != null ) {
-				// remember number of rows affected
-				$this->mAffectedRows = sqlsrv_rows_affected( $ret );
-				if ( !is_null( $identity ) ) {
-					// then we want to get the identity column value we were assigned and save it off
-					$row = sqlsrv_fetch_object( $ret );
+			$this->mScrollableCursor = false;
+			try {
+				$ret = $this->query( $sql );
+			} catch ( Exception $e ) {
+				$this->mScrollableCursor = true;
+				$this->mIgnoreDupKeyErrors = false;
+				throw $e;
+			}
+			$this->mScrollableCursor = true;
+
+			if ( !is_null( $identity ) ) {
+				// then we want to get the identity column value we were assigned and save it off
+				$row = $ret->fetchObject();
+				if( is_object( $row ) ){
 					$this->mInsertId = $row->$identity;
 				}
-				sqlsrv_free_stmt( $ret );
-				continue;
 			}
-			$allOk = false;
 		}
-		return $allOk;
+		$this->mIgnoreDupKeyErrors = false;
+		return $ret;
 	}
 
 	/**
 	 * INSERT SELECT wrapper
 	 * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
-	 * Source items may be literals rather than field names, but strings should be quoted with Database::addQuotes()
-	 * $conds may be "*" to copy the whole table
-	 * srcTable may be an array of tables.
+	 * Source items may be literals rather than field names, but strings should
+	 * be quoted with Database::addQuotes().
 	 * @param string $destTable
-	 * @param array|string $srcTable
+	 * @param array|string $srcTable May be an array of tables.
 	 * @param array $varMap
-	 * @param array $conds
+	 * @param array $conds May be "*" to copy the whole table.
 	 * @param string $fname
 	 * @param array $insertOptions
 	 * @param array $selectOptions
 	 * @throws DBQueryError
 	 * @return null|ResultWrapper
 	 */
-	function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = __METHOD__,
-		$insertOptions = array(), $selectOptions = array() ) {
-		$ret = parent::insertSelect( $destTable, $srcTable, $varMap, $conds, $fname, $insertOptions, $selectOptions );
-
-		if ( $ret === false ) {
-			throw new DBQueryError( $this, $this->getErrors(), $this->lastErrno(), /*$sql*/ '', $fname );
-		} elseif ( $ret != null ) {
-			// remember number of rows affected
-			$this->mAffectedRows = sqlsrv_rows_affected( $ret );
-			return $ret;
+	public function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = __METHOD__,
+		$insertOptions = array(), $selectOptions = array()
+	) {
+		$this->mScrollableCursor = false;
+		try {
+			$ret = parent::insertSelect(
+				$destTable,
+				$srcTable,
+				$varMap,
+				$conds,
+				$fname,
+				$insertOptions,
+				$selectOptions
+			);
+		} catch ( Exception $e ) {
+			$this->mScrollableCursor = true;
+			throw $e;
 		}
-		return null;
+		$this->mScrollableCursor = true;
+
+		return $ret;
 	}
 
 	/**
-	 * Return the next in a sequence, save the value for retrieval via insertId()
-	 * @return
+	 * UPDATE wrapper. Takes a condition array and a SET array.
+	 *
+	 * @param string $table Name of the table to UPDATE. This will be passed through
+	 *                DatabaseBase::tableName().
+	 *
+	 * @param array $values An array of values to SET. For each array element,
+	 *                the key gives the field name, and the value gives the data
+	 *                to set that field to. The data will be quoted by
+	 *                DatabaseBase::addQuotes().
+	 *
+	 * @param array $conds An array of conditions (WHERE). See
+	 *                DatabaseBase::select() for the details of the format of
+	 *                condition arrays. Use '*' to update all rows.
+	 *
+	 * @param string $fname The function name of the caller (from __METHOD__),
+	 *                for logging and profiling.
+	 *
+	 * @param array $options An array of UPDATE options, can be:
+	 *                   - IGNORE: Ignore unique key conflicts
+	 *                   - LOW_PRIORITY: MySQL-specific, see MySQL manual.
+	 * @return bool
 	 */
-	function nextSequenceValue( $seqName ) {
-		if ( !$this->tableExists( 'sequence_' . $seqName ) ) {
-			sqlsrv_query( $this->mConn, "CREATE TABLE [sequence_$seqName] (id INT NOT NULL IDENTITY PRIMARY KEY, junk varchar(10) NULL)" );
+	function update( $table, $values, $conds, $fname = __METHOD__, $options = array() ) {
+		$table = $this->tableName( $table );
+		$binaryColumns = $this->getBinaryColumns( $table );
+
+		$opts = $this->makeUpdateOptions( $options );
+		$sql = "UPDATE $opts $table SET " . $this->makeList( $values, LIST_SET, $binaryColumns );
+
+		if ( $conds !== array() && $conds !== '*' ) {
+			$sql .= " WHERE " . $this->makeList( $conds, LIST_AND, $binaryColumns );
 		}
-		sqlsrv_query( $this->mConn, "INSERT INTO [sequence_$seqName] (junk) VALUES ('')" );
-		$ret = sqlsrv_query( $this->mConn, "SELECT TOP 1 id FROM [sequence_$seqName] ORDER BY id DESC" );
-		$row = sqlsrv_fetch_array( $ret, SQLSRV_FETCH_ASSOC );// KEEP ASSOC THERE, weird weird bug dealing with the return value if you don't
 
-		sqlsrv_free_stmt( $ret );
-		$this->mInsertId = $row['id'];
-		return $row['id'];
+		$this->mScrollableCursor = false;
+		try {
+			$ret = $this->query( $sql );
+		} catch ( Exception $e ) {
+			$this->mScrollableCursor = true;
+			throw $e;
+		}
+		$this->mScrollableCursor = true;
+		return true;
 	}
 
 	/**
-	 * Return the current value of a sequence. Assumes it has ben nextval'ed in this session.
-	 * @return
+	 * Makes an encoded list of strings from an array
+	 * @param array $a Containing the data
+	 * @param int $mode Constant
+	 *      - LIST_COMMA:          comma separated, no field names
+	 *      - LIST_AND:            ANDed WHERE clause (without the WHERE). See
+	 *        the documentation for $conds in DatabaseBase::select().
+	 *      - LIST_OR:             ORed WHERE clause (without the WHERE)
+	 *      - LIST_SET:            comma separated with field names, like a SET clause
+	 *      - LIST_NAMES:          comma separated field names
+	 * @param array $binaryColumns Contains a list of column names that are binary types
+	 *      This is a custom parameter only present for MS SQL.
+	 *
+	 * @throws MWException|DBUnexpectedError
+	 * @return string
 	 */
-	function currentSequenceValue( $seqName ) {
-		$ret = sqlsrv_query( $this->mConn, "SELECT TOP 1 id FROM [sequence_$seqName] ORDER BY id DESC" );
-		if ( $ret !== false ) {
-			$row = sqlsrv_fetch_array( $ret );
-			sqlsrv_free_stmt( $ret );
-			return $row['id'];
-		} else {
-			return $this->nextSequenceValue( $seqName );
+	public function makeList( $a, $mode = LIST_COMMA, $binaryColumns = array() ) {
+		if ( !is_array( $a ) ) {
+			throw new DBUnexpectedError( $this,
+				'DatabaseBase::makeList called with incorrect parameters' );
 		}
+
+		$first = true;
+		$list = '';
+
+		foreach ( $a as $field => $value ) {
+			if ( $mode != LIST_NAMES && isset( $binaryColumns[$field] ) ) {
+				if ( is_array( $value ) ) {
+					foreach ( $value as &$v ) {
+						$v = new MssqlBlob( $v );
+					}
+				} else {
+					$value = new MssqlBlob( $value );
+				}
+			}
+
+			if ( !$first ) {
+				if ( $mode == LIST_AND ) {
+					$list .= ' AND ';
+				} elseif ( $mode == LIST_OR ) {
+					$list .= ' OR ';
+				} else {
+					$list .= ',';
+				}
+			} else {
+				$first = false;
+			}
+
+			if ( ( $mode == LIST_AND || $mode == LIST_OR ) && is_numeric( $field ) ) {
+				$list .= "($value)";
+			} elseif ( ( $mode == LIST_SET ) && is_numeric( $field ) ) {
+				$list .= "$value";
+			} elseif ( ( $mode == LIST_AND || $mode == LIST_OR ) && is_array( $value ) ) {
+				if ( count( $value ) == 0 ) {
+					throw new MWException( __METHOD__ . ": empty input for field $field" );
+				} elseif ( count( $value ) == 1 ) {
+					// Special-case single values, as IN isn't terribly efficient
+					// Don't necessarily assume the single key is 0; we don't
+					// enforce linear numeric ordering on other arrays here.
+					$value = array_values( $value );
+					$list .= $field . " = " . $this->addQuotes( $value[0] );
+				} else {
+					$list .= $field . " IN (" . $this->makeList( $value ) . ") ";
+				}
+			} elseif ( $value === null ) {
+				if ( $mode == LIST_AND || $mode == LIST_OR ) {
+					$list .= "$field IS ";
+				} elseif ( $mode == LIST_SET ) {
+					$list .= "$field = ";
+				}
+				$list .= 'NULL';
+			} else {
+				if ( $mode == LIST_AND || $mode == LIST_OR || $mode == LIST_SET ) {
+					$list .= "$field = ";
+				}
+				$list .= $mode == LIST_NAMES ? $value : $this->addQuotes( $value );
+			}
+		}
+
+		return $list;
 	}
 
-	# Returns the size of a text field, or -1 for "unlimited"
-	function textFieldSize( $table, $field ) {
+	/**
+	 * @param string $table
+	 * @param string $field
+	 * @return int Returns the size of a text field, or -1 for "unlimited"
+	 */
+	public function textFieldSize( $table, $field ) {
 		$table = $this->tableName( $table );
 		$sql = "SELECT CHARACTER_MAXIMUM_LENGTH,DATA_TYPE FROM INFORMATION_SCHEMA.Columns
 			WHERE TABLE_NAME = '$table' AND COLUMN_NAME = '$field'";
@@ -596,40 +881,75 @@ class DatabaseMssql extends DatabaseBase {
 		if ( strtolower( $row['DATA_TYPE'] ) != 'text' ) {
 			$size = $row['CHARACTER_MAXIMUM_LENGTH'];
 		}
+
 		return $size;
 	}
 
 	/**
 	 * Construct a LIMIT query with optional offset
 	 * This is used for query pages
-	 * $sql string SQL query we will append the limit too
-	 * $limit integer the SQL limit
-	 * $offset integer the SQL offset (default false)
-	 * @return mixed|string
+	 *
+	 * @param string $sql SQL query we will append the limit too
+	 * @param int $limit The SQL limit
+	 * @param bool|int $offset The SQL offset (default false)
+	 * @return array|string
 	 */
-	function limitResult( $sql, $limit, $offset = false ) {
+	public function limitResult( $sql, $limit, $offset = false ) {
 		if ( $offset === false || $offset == 0 ) {
 			if ( strpos( $sql, "SELECT" ) === false ) {
 				return "TOP {$limit} " . $sql;
 			} else {
-				return preg_replace( '/\bSELECT(\s*DISTINCT)?\b/Dsi', 'SELECT$1 TOP ' . $limit, $sql, 1 );
+				return preg_replace( '/\bSELECT(\s+DISTINCT)?\b/Dsi',
+					'SELECT$1 TOP ' . $limit, $sql, 1 );
 			}
 		} else {
-			$sql = '
-				SELECT * FROM (
-					SELECT sub2.*, ROW_NUMBER() OVER(ORDER BY sub2.line2) AS line3 FROM (
-						SELECT 1 AS line2, sub1.* FROM (' . $sql . ') AS sub1
-					) as sub2
-				) AS sub3
-				WHERE line3 BETWEEN ' . ( $offset + 1 ) . ' AND ' . ( $offset + $limit );
+			// This one is fun, we need to pull out the select list as well as any ORDER BY clause
+			$select = $orderby = array();
+			$s1 = preg_match( '#SELECT\s+(.+?)\s+FROM#Dis', $sql, $select );
+			$s2 = preg_match( '#(ORDER BY\s+.+?)(\s*FOR XML .*)?$#Dis', $sql, $orderby );
+			$overOrder = $postOrder = '';
+			$first = $offset + 1;
+			$last = $offset + $limit;
+			$sub1 = 'sub_' . $this->mSubqueryId;
+			$sub2 = 'sub_' . ( $this->mSubqueryId + 1 );
+			$this->mSubqueryId += 2;
+			if ( !$s1 ) {
+				// wat
+				throw new DBUnexpectedError( $this, "Attempting to LIMIT a non-SELECT query\n" );
+			}
+			if ( !$s2 ) {
+				// no ORDER BY
+				$overOrder = 'ORDER BY (SELECT 1)';
+			} else {
+				if ( !isset( $orderby[2] ) || !$orderby[2] ) {
+					// don't need to strip it out if we're using a FOR XML clause
+					$sql = str_replace( $orderby[1], '', $sql );
+				}
+				$overOrder = $orderby[1];
+				$postOrder = ' ' . $overOrder;
+			}
+			$sql = "SELECT {$select[1]}
+					FROM (
+						SELECT ROW_NUMBER() OVER({$overOrder}) AS rowNumber, *
+						FROM ({$sql}) {$sub1}
+					) {$sub2}
+					WHERE rowNumber BETWEEN {$first} AND {$last}{$postOrder}";
+
 			return $sql;
 		}
 	}
 
-	// If there is a limit clause, parse it, strip it, and pass the remaining sql through limitResult()
-	// with the appropriate parameters. Not the prettiest solution, but better than building a whole new parser.
-	// This exists becase there are still too many extensions that don't use dynamic sql generation.
-	function LimitToTopN( $sql ) {
+	/**
+	 * If there is a limit clause, parse it, strip it, and pass the remaining
+	 * SQL through limitResult() with the appropriate parameters. Not the
+	 * prettiest solution, but better than building a whole new parser. This
+	 * exists becase there are still too many extensions that don't use dynamic
+	 * sql generation.
+	 *
+	 * @param string $sql
+	 * @return array|mixed|string
+	 */
+	public function LimitToTopN( $sql ) {
 		// Matches: LIMIT {[offset,] row_count | row_count OFFSET offset}
 		$pattern = '/\bLIMIT\s+((([0-9]+)\s*,\s*)?([0-9]+)(\s+OFFSET\s+([0-9]+))?)/i';
 		if ( preg_match( $pattern, $sql, $matches ) ) {
@@ -637,22 +957,20 @@ class DatabaseMssql extends DatabaseBase {
 			$row_count = $matches[4];
 			// offset = $matches[3] OR $matches[6]
 			$offset = $matches[3] or
-				$offset = $matches[6] or
-				$offset = false;
+			$offset = $matches[6] or
+			$offset = false;
 
 			// strip the matching LIMIT clause out
 			$sql = str_replace( $matches[0], '', $sql );
+
 			return $this->limitResult( $sql, $row_count, $offset );
 		}
-		return $sql;
-	}
 
-	function timestamp( $ts = 0 ) {
-		return wfTimestamp( TS_ISO_8601, $ts );
+		return $sql;
 	}
 
 	/**
-	 * @return string wikitext of a link to the server software's web site
+	 * @return string Wikitext of a link to the server software's web site
 	 */
 	public function getSoftwareLink() {
 		return "[{{int:version-db-mssql-url}} MS SQL Server]";
@@ -661,23 +979,40 @@ class DatabaseMssql extends DatabaseBase {
 	/**
 	 * @return string Version information from the database
 	 */
-	function getServerVersion() {
+	public function getServerVersion() {
 		$server_info = sqlsrv_server_info( $this->mConn );
 		$version = 'Error';
 		if ( isset( $server_info['SQLServerVersion'] ) ) {
 			$version = $server_info['SQLServerVersion'];
 		}
+
 		return $version;
 	}
 
-	function tableExists( $table, $fname = __METHOD__, $schema = false ) {
-		$res = sqlsrv_query( $this->mConn, "SELECT * FROM information_schema.tables
-			WHERE table_type='BASE TABLE' AND table_name = '$table'" );
-		if ( $res === false ) {
-			print "Error in tableExists query: " . $this->getErrors();
+	/**
+	 * @param string $table
+	 * @param string $fname
+	 * @return bool
+	 */
+	public function tableExists( $table, $fname = __METHOD__ ) {
+		list( $db, $schema, $table ) = $this->tableName( $table, 'split' );
+
+		if ( $db !== false ) {
+			// remote database
+			wfDebug( "Attempting to call tableExists on a remote table" );
 			return false;
 		}
-		if ( sqlsrv_fetch( $res ) ) {
+
+		if ( $schema === false ) {
+			global $wgDBmwschema;
+			$schema = $wgDBmwschema;
+		}
+
+		$res = $this->query( "SELECT 1 FROM INFORMATION_SCHEMA.TABLES
+			WHERE TABLE_TYPE = 'BASE TABLE'
+			AND TABLE_SCHEMA = '$schema' AND TABLE_NAME = '$table'" );
+
+		if ( $res->numRows() ) {
 			return true;
 		} else {
 			return false;
@@ -686,40 +1021,53 @@ class DatabaseMssql extends DatabaseBase {
 
 	/**
 	 * Query whether a given column exists in the mediawiki schema
+	 * @param string $table
+	 * @param string $field
+	 * @param string $fname
 	 * @return bool
 	 */
-	function fieldExists( $table, $field, $fname = __METHOD__ ) {
-		$table = $this->tableName( $table );
-		$res = sqlsrv_query( $this->mConn, "SELECT DATA_TYPE FROM INFORMATION_SCHEMA.Columns
-			WHERE TABLE_NAME = '$table' AND COLUMN_NAME = '$field'" );
-		if ( $res === false ) {
-			print "Error in fieldExists query: " . $this->getErrors();
+	public function fieldExists( $table, $field, $fname = __METHOD__ ) {
+		list( $db, $schema, $table ) = $this->tableName( $table, 'split' );
+
+		if ( $db !== false ) {
+			// remote database
+			wfDebug( "Attempting to call fieldExists on a remote table" );
 			return false;
 		}
-		if ( sqlsrv_fetch( $res ) ) {
+
+		$res = $this->query( "SELECT 1 FROM INFORMATION_SCHEMA.COLUMNS
+			WHERE TABLE_SCHEMA = '$schema' AND TABLE_NAME = '$table' AND COLUMN_NAME = '$field'" );
+
+		if ( $res->numRows() ) {
 			return true;
 		} else {
 			return false;
 		}
 	}
 
-	function fieldInfo( $table, $field ) {
-		$table = $this->tableName( $table );
-		$res = sqlsrv_query( $this->mConn, "SELECT * FROM INFORMATION_SCHEMA.Columns
-			WHERE TABLE_NAME = '$table' AND COLUMN_NAME = '$field'" );
-		if ( $res === false ) {
-			print "Error in fieldInfo query: " . $this->getErrors();
+	public function fieldInfo( $table, $field ) {
+		list( $db, $schema, $table ) = $this->tableName( $table, 'split' );
+
+		if ( $db !== false ) {
+			// remote database
+			wfDebug( "Attempting to call fieldInfo on a remote table" );
 			return false;
 		}
-		$meta = $this->fetchRow( $res );
+
+		$res = $this->query( "SELECT * FROM INFORMATION_SCHEMA.COLUMNS
+			WHERE TABLE_SCHEMA = '$schema' AND TABLE_NAME = '$table' AND COLUMN_NAME = '$field'" );
+
+		$meta = $res->fetchRow();
 		if ( $meta ) {
 			return new MssqlField( $meta );
 		}
+
 		return false;
 	}
 
 	/**
 	 * Begin a transaction, committing any previously open transaction
+	 * @param string $fname
 	 */
 	protected function doBegin( $fname = __METHOD__ ) {
 		sqlsrv_begin_transaction( $this->mConn );
@@ -728,6 +1076,7 @@ class DatabaseMssql extends DatabaseBase {
 
 	/**
 	 * End a transaction
+	 * @param string $fname
 	 */
 	protected function doCommit( $fname = __METHOD__ ) {
 		sqlsrv_commit( $this->mConn );
@@ -737,6 +1086,7 @@ class DatabaseMssql extends DatabaseBase {
 	/**
 	 * Rollback a transaction.
 	 * No-op on non-transactional databases.
+	 * @param string $fname
 	 */
 	protected function doRollback( $fname = __METHOD__ ) {
 		sqlsrv_rollback( $this->mConn );
@@ -747,7 +1097,7 @@ class DatabaseMssql extends DatabaseBase {
 	 * Escapes a identifier for use inm SQL.
 	 * Throws an exception if it is invalid.
 	 * Reference: http://msdn.microsoft.com/en-us/library/aa224033%28v=SQL.80%29.aspx
-	 * @param $identifier
+	 * @param string $identifier
 	 * @throws MWException
 	 * @return string
 	 */
@@ -758,153 +1108,82 @@ class DatabaseMssql extends DatabaseBase {
 		if ( strlen( $identifier ) > 128 ) {
 			throw new MWException( "The identifier '$identifier' is too long (max. 128)" );
 		}
-		if ( ( strpos( $identifier, '[' ) !== false ) || ( strpos( $identifier, ']' ) !== false ) ) {
-			// It may be allowed if you quoted with double quotation marks, but that would break if QUOTED_IDENTIFIER is OFF
-			throw new MWException( "You can't use square brackers in the identifier '$identifier'" );
+		if ( ( strpos( $identifier, '[' ) !== false )
+			|| ( strpos( $identifier, ']' ) !== false )
+		) {
+			// It may be allowed if you quoted with double quotation marks, but
+			// that would break if QUOTED_IDENTIFIER is OFF
+			throw new MWException( "Square brackets are not allowed in '$identifier'" );
 		}
+
 		return "[$identifier]";
 	}
 
 	/**
-	 * Initial setup.
-	 * Precondition: This object is connected as the superuser.
-	 * Creates the database, schema, user and login.
+	 * @param string $s
+	 * @return string
 	 */
-	function initial_setup( $dbName, $newUser, $loginPassword ) {
-		$dbName = $this->escapeIdentifier( $dbName );
-
-		// It is not clear what can be used as a login,
-		// From http://msdn.microsoft.com/en-us/library/ms173463.aspx
-		// a sysname may be the same as an identifier.
-		$newUser = $this->escapeIdentifier( $newUser );
-		$loginPassword = $this->addQuotes( $loginPassword );
-
-		$this->doQuery( "CREATE DATABASE $dbName;" );
-		$this->doQuery( "USE $dbName;" );
-		$this->doQuery( "CREATE SCHEMA $dbName;" );
-		$this->doQuery( "
-						CREATE
-							LOGIN $newUser
-						WITH
-							PASSWORD=$loginPassword
-						;
-					" );
-		$this->doQuery( "
-						CREATE
-							USER $newUser
-						FOR
-							LOGIN $newUser
-						WITH
-							DEFAULT_SCHEMA=$dbName
-						;
-					" );
-		$this->doQuery( "
-						GRANT
-							BACKUP DATABASE,
-							BACKUP LOG,
-							CREATE DEFAULT,
-							CREATE FUNCTION,
-							CREATE PROCEDURE,
-							CREATE RULE,
-							CREATE TABLE,
-							CREATE VIEW,
-							CREATE FULLTEXT CATALOG
-						ON
-							DATABASE::$dbName
-						TO $newUser
-						;
-					" );
-		$this->doQuery( "
-						GRANT
-							CONTROL
-						ON
-							SCHEMA::$dbName
-						TO $newUser
-						;
-					" );
-	}
-
-	function encodeBlob( $b ) {
-	// we can't have zero's and such, this is a simple encoding to make sure we don't barf
-		return base64_encode( $b );
-	}
-
-	function decodeBlob( $b ) {
-	// we can't have zero's and such, this is a simple encoding to make sure we don't barf
-	return base64_decode( $b );
+	public function strencode( $s ) { # Should not be called by us
+		return str_replace( "'", "''", $s );
 	}
 
 	/**
-	 * @private
+	 * @param string $s
 	 * @return string
 	 */
-	function tableNamesWithUseIndexOrJOIN( $tables, $use_index = array(), $join_conds = array() ) {
-		$ret = array();
-		$retJOIN = array();
-		$use_index_safe = is_array( $use_index ) ? $use_index : array();
-		$join_conds_safe = is_array( $join_conds ) ? $join_conds : array();
-		foreach ( $tables as $table ) {
-			// Is there a JOIN and INDEX clause for this table?
-			if ( isset( $join_conds_safe[$table] ) && isset( $use_index_safe[$table] ) ) {
-				$tableClause = $join_conds_safe[$table][0] . ' ' . $this->tableName( $table );
-				$tableClause .= ' ' . $this->useIndexClause( implode( ',', (array)$use_index_safe[$table] ) );
-				$tableClause .= ' ON (' . $this->makeList( (array)$join_conds_safe[$table][1], LIST_AND ) . ')';
-				$retJOIN[] = $tableClause;
-			// Is there an INDEX clause?
-			} elseif ( isset( $use_index_safe[$table] ) ) {
-				$tableClause = $this->tableName( $table );
-				$tableClause .= ' ' . $this->useIndexClause( implode( ',', (array)$use_index_safe[$table] ) );
-				$ret[] = $tableClause;
-			// Is there a JOIN clause?
-			} elseif ( isset( $join_conds_safe[$table] ) ) {
-				$tableClause = $join_conds_safe[$table][0] . ' ' . $this->tableName( $table );
-				$tableClause .= ' ON (' . $this->makeList( (array)$join_conds_safe[$table][1], LIST_AND ) . ')';
-				$retJOIN[] = $tableClause;
-			} else {
-				$tableClause = $this->tableName( $table );
-				$ret[] = $tableClause;
-			}
-		}
-		// We can't separate explicit JOIN clauses with ',', use ' ' for those
-		$straightJoins = !empty( $ret ) ? implode( ',', $ret ) : "";
-		$otherJoins = !empty( $retJOIN ) ? implode( ' ', $retJOIN ) : "";
-		// Compile our final table clause
-		return implode( ' ', array( $straightJoins, $otherJoins ) );
-	}
-
-	function strencode( $s ) { # Should not be called by us
-		return str_replace( "'", "''", $s );
-	}
-
-	function addQuotes( $s ) {
-		if ( $s instanceof Blob ) {
-			return "'" . $s->fetch( $s ) . "'";
+	public function addQuotes( $s ) {
+		if ( $s instanceof MssqlBlob ) {
+			return $s->fetch();
+		} elseif ( $s instanceof Blob ) {
+			// this shouldn't really ever be called, but it's here if needed
+			// (and will quite possibly make the SQL error out)
+			$blob = new MssqlBlob( $s->fetch() );
+			return $blob->fetch();
 		} else {
+			if ( is_bool( $s ) ) {
+				$s = $s ? 1 : 0;
+			}
 			return parent::addQuotes( $s );
 		}
 	}
 
+	/**
+	 * @param string $s
+	 * @return string
+	 */
 	public function addIdentifierQuotes( $s ) {
 		// http://msdn.microsoft.com/en-us/library/aa223962.aspx
 		return '[' . $s . ']';
 	}
 
+	/**
+	 * @param string $name
+	 * @return bool
+	 */
 	public function isQuotedIdentifier( $name ) {
-		return $name[0] == '[' && substr( $name, -1, 1 ) == ']';
+		return strlen( $name ) && $name[0] == '[' && substr( $name, -1, 1 ) == ']';
 	}
 
-	function selectDB( $db ) {
-		return ( $this->query( "SET DATABASE $db" ) !== false );
+	/**
+	 * @param string $db
+	 * @return bool
+	 */
+	public function selectDB( $db ) {
+		try {
+			$this->mDBname = $db;
+			$this->query( "USE $db" );
+			return true;
+		} catch ( Exception $e ) {
+			return false;
+		}
 	}
 
 	/**
-	 * @private
-	 *
-	 * @param array $options an associative array of options to be turned into
-	 *                 an SQL query, valid keys are listed in the function.
-	 * @return Array
+	 * @param array $options An associative array of options to be turned into
+	 *   an SQL query, valid keys are listed in the function.
+	 * @return array
 	 */
-	function makeSelectOptions( $options ) {
+	public function makeSelectOptions( $options ) {
 		$tailOpts = '';
 		$startOpts = '';
 
@@ -919,10 +1198,15 @@ class DatabaseMssql extends DatabaseBase {
 
 		$tailOpts .= $this->makeOrderBy( $options );
 
-		if ( isset( $noKeyOptions['DISTINCT'] ) && isset( $noKeyOptions['DISTINCTROW'] ) ) {
+		if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
 			$startOpts .= 'DISTINCT';
 		}
 
+		if ( isset( $noKeyOptions['FOR XML'] ) ) {
+			// used in group concat field emulation
+			$tailOpts .= " FOR XML PATH('')";
+		}
+
 		// we want this to be compatible with the output of parent::makeSelectOptions()
 		return array( $startOpts, '', $tailOpts, '' );
 	}
@@ -931,27 +1215,165 @@ class DatabaseMssql extends DatabaseBase {
 	 * Get the type of the DBMS, as it appears in $wgDBtype.
 	 * @return string
 	 */
-	function getType() {
+	public function getType() {
 		return 'mssql';
 	}
 
-	function buildConcat( $stringList ) {
+	/**
+	 * @param array $stringList
+	 * @return string
+	 */
+	public function buildConcat( $stringList ) {
 		return implode( ' + ', $stringList );
 	}
 
+	/**
+	 * Build a GROUP_CONCAT or equivalent statement for a query.
+	 * MS SQL doesn't have GROUP_CONCAT so we emulate it with other stuff (and boy is it nasty)
+	 *
+	 * This is useful for combining a field for several rows into a single string.
+	 * NULL values will not appear in the output, duplicated values will appear,
+	 * and the resulting delimiter-separated values have no defined sort order.
+	 * Code using the results may need to use the PHP unique() or sort() methods.
+	 *
+	 * @param string $delim Glue to bind the results together
+	 * @param string|array $table Table name
+	 * @param string $field Field name
+	 * @param string|array $conds Conditions
+	 * @param string|array $join_conds Join conditions
+	 * @return string SQL text
+	 * @since 1.23
+	 */
+	public function buildGroupConcatField( $delim, $table, $field, $conds = '',
+		$join_conds = array()
+	) {
+		$gcsq = 'gcsq_' . $this->mSubqueryId;
+		$this->mSubqueryId++;
+
+		$delimLen = strlen( $delim );
+		$fld = "{$field} + {$this->addQuotes( $delim )}";
+		$sql = "(SELECT LEFT({$field}, LEN({$field}) - {$delimLen}) FROM ("
+			. $this->selectSQLText( $table, $fld, $conds, null, array( 'FOR XML' ), $join_conds )
+			. ") {$gcsq} ({$field}))";
+
+		return $sql;
+	}
+
+	/**
+	 * @return string
+	 */
 	public function getSearchEngine() {
 		return "SearchMssql";
 	}
 
 	/**
-	 * Since MSSQL doesn't recognize the infinity keyword, set date manually.
-	 * @todo Remove magic date
+	 * Returns an associative array for fields that are of type varbinary, binary, or image
+	 * $table can be either a raw table name or passed through tableName() first
+	 * @param string $table
+	 * @return array
+	 */
+	private function getBinaryColumns( $table ) {
+		$tableRawArr = explode( '.', preg_replace( '#\[([^\]]*)\]#', '$1', $table ) );
+		$tableRaw = array_pop( $tableRawArr );
+
+		if ( $this->mBinaryColumnCache === null ) {
+			$this->populateColumnCaches();
+		}
+
+		return isset( $this->mBinaryColumnCache[$tableRaw] )
+			? $this->mBinaryColumnCache[$tableRaw]
+			: array();
+	}
+
+	/**
+	 * @param string $table
+	 * @return array
+	 */
+	private function getBitColumns( $table ) {
+		$tableRawArr = explode( '.', preg_replace( '#\[([^\]]*)\]#', '$1', $table ) );
+		$tableRaw = array_pop( $tableRawArr );
+
+		if ( $this->mBitColumnCache === null ) {
+			$this->populateColumnCaches();
+		}
+
+		return isset( $this->mBitColumnCache[$tableRaw] )
+			? $this->mBitColumnCache[$tableRaw]
+			: array();
+	}
+
+	private function populateColumnCaches() {
+		$res = $this->select( 'INFORMATION_SCHEMA.COLUMNS', '*',
+			array(
+				'TABLE_CATALOG' => $this->mDBname,
+				'TABLE_SCHEMA' => $this->mSchema,
+				'DATA_TYPE' => array( 'varbinary', 'binary', 'image', 'bit' )
+			) );
+
+		$this->mBinaryColumnCache = array();
+		$this->mBitColumnCache = array();
+		foreach ( $res as $row ) {
+			if ( $row->DATA_TYPE == 'bit' ) {
+				$this->mBitColumnCache[$row->TABLE_NAME][$row->COLUMN_NAME] = $row;
+			} else {
+				$this->mBinaryColumnCache[$row->TABLE_NAME][$row->COLUMN_NAME] = $row;
+			}
+		}
+	}
+
+	/**
+	 * @param string $name
+	 * @param string $format
+	 * @return string
+	 */
+	function tableName( $name, $format = 'quoted' ) {
+		# Replace reserved words with better ones
+		switch ( $name ) {
+			case 'user':
+				return $this->realTableName( 'mwuser', $format );
+			default:
+				return $this->realTableName( $name, $format );
+		}
+	}
+
+	/**
+	 * call this instead of tableName() in the updater when renaming tables
+	 * @param string $name
+	 * @param string $format One of quoted, raw, or split
 	 * @return string
 	 */
-	public function getInfinity() {
-		return '3000-01-31 00:00:00.000';
+	function realTableName( $name, $format = 'quoted' ) {
+		$table = parent::tableName( $name, $format );
+		if ( $format == 'split' ) {
+			// Used internally, we want the schema split off from the table name and returned
+			// as a list with 3 elements (database, schema, table)
+			$table = explode( '.', $table );
+			while ( count( $table ) < 3 ) {
+				array_unshift( $table, false );
+			}
+		}
+		return $table;
 	}
 
+	/**
+	 * Called in the installer and updater.
+	 * Probably doesn't need to be called anywhere else in the codebase.
+	 * @param bool|null $value
+	 * @return bool|null
+	 */
+	public function prepareStatements( $value = null ) {
+		return wfSetVar( $this->mPrepareStatements, $value );
+	}
+
+	/**
+	 * Called in the installer and updater.
+	 * Probably doesn't need to be called anywhere else in the codebase.
+	 * @param bool|null $value
+	 * @return bool|null
+	 */
+	public function scrollableCursor( $value = null ) {
+		return wfSetVar( $this->mScrollableCursor, $value );
+	}
 } // end DatabaseMssql class
 
 /**
@@ -960,10 +1382,11 @@ class DatabaseMssql extends DatabaseBase {
  * @ingroup Database
  */
 class MssqlField implements Field {
-	private $name, $tablename, $default, $max_length, $nullable, $type;
+	private $name, $tableName, $default, $max_length, $nullable, $type;
+
 	function __construct( $info ) {
 		$this->name = $info['COLUMN_NAME'];
-		$this->tablename = $info['TABLE_NAME'];
+		$this->tableName = $info['TABLE_NAME'];
 		$this->default = $info['COLUMN_DEFAULT'];
 		$this->max_length = $info['CHARACTER_MAXIMUM_LENGTH'];
 		$this->nullable = !( strtolower( $info['IS_NULLABLE'] ) == 'no' );
@@ -995,208 +1418,105 @@ class MssqlField implements Field {
 	}
 }
 
-/**
- * The MSSQL PHP driver doesn't support sqlsrv_num_rows, so we recall all rows into an array and maintain our
- * own cursor index into that array...This is similar to the way the Oracle driver handles this same issue
- *
- * @ingroup Database
- */
-class MssqlResult {
-
-	public function __construct( $queryresult = false ) {
-		$this->mCursor = 0;
-		$this->mRows = array();
-		$this->mNumFields = sqlsrv_num_fields( $queryresult );
-		$this->mFieldMeta = sqlsrv_field_metadata( $queryresult );
+class MssqlBlob extends Blob {
+	public function __construct( $data ) {
+		if ( $data instanceof MssqlBlob ) {
+			return $data;
+		} elseif ( $data instanceof Blob ) {
+			$this->mData = $data->fetch();
+		} elseif ( is_array( $data ) && is_object( $data ) ) {
+			$this->mData = serialize( $data );
+		} else {
+			$this->mData = $data;
+		}
+	}
 
-		$rows = sqlsrv_fetch_array( $queryresult, SQLSRV_FETCH_ASSOC );
+	/**
+	 * Returns an unquoted hex representation of a binary string
+	 * for insertion into varbinary-type fields
+	 * @return string
+	 */
+	public function fetch() {
+		if ( $this->mData === null ) {
+			return 'null';
+		}
 
-		foreach ( $rows as $row ) {
-			if ( $row !== null ) {
-				foreach ( $row as $k => $v ) {
-					if ( is_object( $v ) && method_exists( $v, 'format' ) ) {// DateTime Object
-						$row[$k] = $v->format( "Y-m-d\TH:i:s\Z" );
-					}
-				}
-				$this->mRows[] = $row;// read results into memory, cursors are not supported
-			}
+		$ret = '0x';
+		$dataLength = strlen( $this->mData );
+		for ( $i = 0; $i < $dataLength; $i++ ) {
+			$ret .= bin2hex( pack( 'C', ord( $this->mData[$i] ) ) );
 		}
-		$this->mRowCount = count( $this->mRows );
-		sqlsrv_free_stmt( $queryresult );
+
+		return $ret;
 	}
+}
 
-	private function array_to_obj( $array, &$obj ) {
-		foreach ( $array as $key => $value ) {
-			if ( is_array( $value ) ) {
-				$obj->$key = new stdClass();
-				$this->array_to_obj( $value, $obj->$key );
-			} else {
-				if ( !empty( $key ) ) {
-					$obj->$key = $value;
-				}
-			}
+class MssqlResultWrapper extends ResultWrapper {
+	private $mSeekTo = null;
+
+	/**
+	 * @return stdClass|bool
+	 */
+	public function fetchObject() {
+		$res = $this->result;
+
+		if ( $this->mSeekTo !== null ) {
+			$result = sqlsrv_fetch_object( $res, 'stdClass', array(),
+				SQLSRV_SCROLL_ABSOLUTE, $this->mSeekTo );
+			$this->mSeekTo = null;
+		} else {
+			$result = sqlsrv_fetch_object( $res );
 		}
-		return $obj;
-	}
 
-	public function fetch( $mode = SQLSRV_FETCH_BOTH, $object_class = 'stdClass' ) {
-		if ( $this->mCursor >= $this->mRowCount || $this->mRowCount == 0 ) {
+		// MediaWiki expects us to return boolean false when there are no more rows instead of null
+		if ( $result === null ) {
 			return false;
 		}
-		$arrNum = array();
-		if ( $mode == SQLSRV_FETCH_NUMERIC || $mode == SQLSRV_FETCH_BOTH ) {
-			foreach ( $this->mRows[$this->mCursor] as $value ) {
-				$arrNum[] = $value;
-			}
-		}
-		switch ( $mode ) {
-			case SQLSRV_FETCH_ASSOC:
-				$ret = $this->mRows[$this->mCursor];
-				break;
-			case SQLSRV_FETCH_NUMERIC:
-				$ret = $arrNum;
-				break;
-			case 'OBJECT':
-				$o = new $object_class;
-				$ret = $this->array_to_obj( $this->mRows[$this->mCursor], $o );
-				break;
-			case SQLSRV_FETCH_BOTH:
-			default:
-				$ret = $this->mRows[$this->mCursor] + $arrNum;
-				break;
-		}
 
-		$this->mCursor++;
-		return $ret;
+		return $result;
 	}
 
-	public function get( $pos, $fld ) {
-		return $this->mRows[$pos][$fld];
-	}
+	/**
+	 * @return array|bool
+	 */
+	public function fetchRow() {
+		$res = $this->result;
 
-	public function numrows() {
-		return $this->mRowCount;
-	}
+		if ( $this->mSeekTo !== null ) {
+			$result = sqlsrv_fetch_array( $res, SQLSRV_FETCH_BOTH,
+				SQLSRV_SCROLL_ABSOLUTE, $this->mSeekTo );
+			$this->mSeekTo = null;
+		} else {
+			$result = sqlsrv_fetch_array( $res );
+		}
 
-	public function seek( $iRow ) {
-		$this->mCursor = min( $iRow, $this->mRowCount );
-	}
+		// MediaWiki expects us to return boolean false when there are no more rows instead of null
+		if ( $result === null ) {
+			return false;
+		}
 
-	public function numfields() {
-		return $this->mNumFields;
+		return $result;
 	}
 
-	public function fieldname( $nr ) {
-		$arrKeys = array_keys( $this->mRows[0] );
-		return $arrKeys[$nr];
-	}
+	/**
+	 * @param int $row
+	 * @return bool
+	 */
+	public function seek( $row ) {
+		$res = $this->result;
 
-	public function fieldtype( $nr ) {
-		$i = 0;
-		$intType = -1;
-		foreach ( $this->mFieldMeta as $meta ) {
-			if ( $nr == $i ) {
-				$intType = $meta['Type'];
-				break;
-			}
-			$i++;
-		}
-		// http://msdn.microsoft.com/en-us/library/cc296183.aspx contains type table
-		switch ( $intType ) {
-			case SQLSRV_SQLTYPE_BIGINT:
-				$strType = 'bigint';
-				break;
-			case SQLSRV_SQLTYPE_BINARY:
-				$strType = 'binary';
-				break;
-			case SQLSRV_SQLTYPE_BIT:
-				$strType = 'bit';
-				break;
-			case SQLSRV_SQLTYPE_CHAR:
-				$strType = 'char';
-				break;
-			case SQLSRV_SQLTYPE_DATETIME:
-				$strType = 'datetime';
-				break;
-			case SQLSRV_SQLTYPE_DECIMAL: // ($precision, $scale)
-				$strType = 'decimal';
-				break;
-			case SQLSRV_SQLTYPE_FLOAT:
-				$strType = 'float';
-				break;
-			case SQLSRV_SQLTYPE_IMAGE:
-				$strType = 'image';
-				break;
-			case SQLSRV_SQLTYPE_INT:
-				$strType = 'int';
-				break;
-			case SQLSRV_SQLTYPE_MONEY:
-				$strType = 'money';
-				break;
-			case SQLSRV_SQLTYPE_NCHAR: // ($charCount):
-				$strType = 'nchar';
-				break;
-			case SQLSRV_SQLTYPE_NUMERIC: // ($precision, $scale):
-				$strType = 'numeric';
-				break;
-			case SQLSRV_SQLTYPE_NVARCHAR: // ($charCount)
-				$strType = 'nvarchar';
-				break;
-			// case SQLSRV_SQLTYPE_NVARCHAR('max'):
-			//	 $strType = 'nvarchar(MAX)';
-			//	 break;
-			case SQLSRV_SQLTYPE_NTEXT:
-				$strType = 'ntext';
-				break;
-			case SQLSRV_SQLTYPE_REAL:
-				$strType = 'real';
-				break;
-			case SQLSRV_SQLTYPE_SMALLDATETIME:
-				$strType = 'smalldatetime';
-				break;
-			case SQLSRV_SQLTYPE_SMALLINT:
-				$strType = 'smallint';
-				break;
-			case SQLSRV_SQLTYPE_SMALLMONEY:
-				$strType = 'smallmoney';
-				break;
-			case SQLSRV_SQLTYPE_TEXT:
-				$strType = 'text';
-				break;
-			case SQLSRV_SQLTYPE_TIMESTAMP:
-				$strType = 'timestamp';
-				break;
-			case SQLSRV_SQLTYPE_TINYINT:
-				$strType = 'tinyint';
-				break;
-			case SQLSRV_SQLTYPE_UNIQUEIDENTIFIER:
-				$strType = 'uniqueidentifier';
-				break;
-			case SQLSRV_SQLTYPE_UDT:
-				$strType = 'UDT';
-				break;
-			case SQLSRV_SQLTYPE_VARBINARY: // ($byteCount)
-				$strType = 'varbinary';
-				break;
-			// case SQLSRV_SQLTYPE_VARBINARY('max'):
-			//	 $strType = 'varbinary(MAX)';
-			//	 break;
-			case SQLSRV_SQLTYPE_VARCHAR: // ($charCount)
-				$strType = 'varchar';
-				break;
-			// case SQLSRV_SQLTYPE_VARCHAR('max'):
-			//	 $strType = 'varchar(MAX)';
-			//	 break;
-			case SQLSRV_SQLTYPE_XML:
-				$strType = 'xml';
-				break;
-			default:
-				$strType = $intType;
+		// check bounds
+		$numRows = $this->db->numRows( $res );
+		$row = intval( $row );
+
+		if ( $numRows === 0 ) {
+			return false;
+		} elseif ( $row < 0 || $row > $numRows - 1 ) {
+			return false;
 		}
-		return $strType;
-	}
 
-	public function free() {
-		unset( $this->mRows );
+		// Unlike MySQL, the seek actually happens on the next access
+		$this->mSeekTo = $row;
+		return true;
 	}
 }
diff --git a/includes/db/DatabaseMysql.php b/includes/db/DatabaseMysql.php
index 956bb694..dc4a67df 100644
--- a/includes/db/DatabaseMysql.php
+++ b/includes/db/DatabaseMysql.php
@@ -28,10 +28,9 @@
  * @see Database
  */
 class DatabaseMysql extends DatabaseMysqlBase {
-
 	/**
-	 * @param $sql string
-	 * @return resource
+	 * @param string $sql
+	 * @return resource False on error
 	 */
 	protected function doQuery( $sql ) {
 		if ( $this->bufferResults() ) {
@@ -39,14 +38,23 @@ class DatabaseMysql extends DatabaseMysqlBase {
 		} else {
 			$ret = mysql_unbuffered_query( $sql, $this->mConn );
 		}
+
 		return $ret;
 	}
 
+	/**
+	 * @param string $realServer
+	 * @return bool|resource MySQL Database connection or false on failure to connect
+	 * @throws DBConnectionError
+	 */
 	protected function mysqlConnect( $realServer ) {
 		# Fail now
 		# Otherwise we get a suppressed fatal error, which is very hard to track down
 		if ( !extension_loaded( 'mysql' ) ) {
-			throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
+			throw new DBConnectionError(
+				$this,
+				"MySQL functions missing, have you compiled PHP with the --with-mysql option?\n"
+			);
 		}
 
 		$connFlags = 0;
@@ -81,6 +89,18 @@ class DatabaseMysql extends DatabaseMysqlBase {
 	}
 
 	/**
+	 * @param string $charset
+	 * @return bool
+	 */
+	protected function mysqlSetCharset( $charset ) {
+		if ( function_exists( 'mysql_set_charset' ) ) {
+			return mysql_set_charset( $charset, $this->mConn );
+		} else {
+			return $this->query( 'SET NAMES ' . $charset, __METHOD__ );
+		}
+	}
+
+	/**
 	 * @return bool
 	 */
 	protected function closeConnection() {
@@ -113,11 +133,12 @@ class DatabaseMysql extends DatabaseMysqlBase {
 	}
 
 	/**
-	 * @param $db
+	 * @param string $db
 	 * @return bool
 	 */
 	function selectDB( $db ) {
 		$this->mDBname = $db;
+
 		return mysql_select_db( $db, $this->mConn );
 	}
 
@@ -156,6 +177,10 @@ class DatabaseMysql extends DatabaseMysqlBase {
 		return mysql_field_name( $res, $n );
 	}
 
+	protected function mysqlFieldType( $res, $n ) {
+		return mysql_field_type( $res, $n );
+	}
+
 	protected function mysqlDataSeek( $res, $row ) {
 		return mysql_data_seek( $res, $row );
 	}
diff --git a/includes/db/DatabaseMysqlBase.php b/includes/db/DatabaseMysqlBase.php
index 8f12b92d..ba0f39ff 100644
--- a/includes/db/DatabaseMysqlBase.php
+++ b/includes/db/DatabaseMysqlBase.php
@@ -33,6 +33,11 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	/** @var MysqlMasterPos */
 	protected $lastKnownSlavePos;
 
+	/** @var null|int */
+	protected $mFakeSlaveLag = null;
+
+	protected $mFakeMaster = false;
+
 	/**
 	 * @return string
 	 */
@@ -41,15 +46,15 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	}
 
 	/**
-	 * @param $server string
-	 * @param $user string
-	 * @param $password string
-	 * @param $dbName string
+	 * @param string $server
+	 * @param string $user
+	 * @param string $password
+	 * @param string $dbName
+	 * @throws Exception|DBConnectionError
 	 * @return bool
-	 * @throws DBConnectionError
 	 */
 	function open( $server, $user, $password, $dbName ) {
-		global $wgAllDBsAreLocalhost, $wgDBmysql5, $wgSQLMode;
+		global $wgAllDBsAreLocalhost, $wgSQLMode;
 		wfProfileIn( __METHOD__ );
 
 		# Debugging hack -- fake cluster
@@ -76,6 +81,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		} catch ( Exception $ex ) {
 			wfProfileOut( "dbconnect-$server" );
 			wfProfileOut( __METHOD__ );
+			$this->restoreErrorHandler();
 			throw $ex;
 		}
 		$error = $this->restoreErrorHandler();
@@ -87,13 +93,14 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 			if ( !$error ) {
 				$error = $this->lastError();
 			}
-			wfLogDBError( "Error connecting to {$this->mServer}: $error\n" );
+			wfLogDBError( "Error connecting to {$this->mServer}: $error" );
 			wfDebug( "DB connection error\n" .
 				"Server: $server, User: $user, Password: " .
 				substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
 
 			wfProfileOut( __METHOD__ );
-			return $this->reportConnectionError( $error );
+
+			$this->reportConnectionError( $error );
 		}
 
 		if ( $dbName != '' ) {
@@ -101,44 +108,74 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 			$success = $this->selectDB( $dbName );
 			wfRestoreWarnings();
 			if ( !$success ) {
-				wfLogDBError( "Error selecting database $dbName on server {$this->mServer}\n" );
+				wfLogDBError( "Error selecting database $dbName on server {$this->mServer}" );
 				wfDebug( "Error selecting database $dbName on server {$this->mServer} " .
 					"from client host " . wfHostname() . "\n" );
 
 				wfProfileOut( __METHOD__ );
-				return $this->reportConnectionError( "Error selecting database $dbName" );
+
+				$this->reportConnectionError( "Error selecting database $dbName" );
 			}
 		}
 
-		// Tell the server we're communicating with it in UTF-8.
-		// This may engage various charset conversions.
-		if ( $wgDBmysql5 ) {
-			$this->query( 'SET NAMES utf8', __METHOD__ );
-		} else {
-			$this->query( 'SET NAMES binary', __METHOD__ );
+		// Tell the server what we're communicating with
+		if ( !$this->connectInitCharset() ) {
+			$this->reportConnectionError( "Error setting character set" );
 		}
+
 		// Set SQL mode, default is turning them all off, can be overridden or skipped with null
 		if ( is_string( $wgSQLMode ) ) {
 			$mode = $this->addQuotes( $wgSQLMode );
-			$this->query( "SET sql_mode = $mode", __METHOD__ );
+			// Use doQuery() to avoid opening implicit transactions (DBO_TRX)
+			$success = $this->doQuery( "SET sql_mode = $mode", __METHOD__ );
+			if ( !$success ) {
+				wfLogDBError( "Error setting sql_mode to $mode on server {$this->mServer}" );
+				wfProfileOut( __METHOD__ );
+				$this->reportConnectionError( "Error setting sql_mode to $mode" );
+			}
 		}
 
 		$this->mOpened = true;
 		wfProfileOut( __METHOD__ );
+
 		return true;
 	}
 
 	/**
+	 * Set the character set information right after connection
+	 * @return bool
+	 */
+	protected function connectInitCharset() {
+		global $wgDBmysql5;
+
+		if ( $wgDBmysql5 ) {
+			// Tell the server we're communicating with it in UTF-8.
+			// This may engage various charset conversions.
+			return $this->mysqlSetCharset( 'utf8' );
+		} else {
+			return $this->mysqlSetCharset( 'binary' );
+		}
+	}
+
+	/**
 	 * Open a connection to a MySQL server
 	 *
-	 * @param $realServer string
+	 * @param string $realServer
 	 * @return mixed Raw connection
 	 * @throws DBConnectionError
 	 */
 	abstract protected function mysqlConnect( $realServer );
 
 	/**
-	 * @param $res ResultWrapper
+	 * Set the character set of the MySQL link
+	 *
+	 * @param string $charset
+	 * @return bool
+	 */
+	abstract protected function mysqlSetCharset( $charset );
+
+	/**
+	 * @param ResultWrapper|resource $res
 	 * @throws DBUnexpectedError
 	 */
 	function freeResult( $res ) {
@@ -156,14 +193,14 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	/**
 	 * Free result memory
 	 *
-	 * @param $res Raw result
+	 * @param resource $res Raw result
 	 * @return bool
 	 */
 	abstract protected function mysqlFreeResult( $res );
 
 	/**
-	 * @param $res ResultWrapper
-	 * @return object|bool
+	 * @param ResultWrapper|resource $res
+	 * @return stdClass|bool
 	 * @throws DBUnexpectedError
 	 */
 	function fetchObject( $res ) {
@@ -180,21 +217,25 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		// these are the only errors mysql_fetch_object can cause.
 		// See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 		if ( $errno == 2000 || $errno == 2013 ) {
-			throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
+			throw new DBUnexpectedError(
+				$this,
+				'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
+			);
 		}
+
 		return $row;
 	}
 
 	/**
 	 * Fetch a result row as an object
 	 *
-	 * @param $res Raw result
+	 * @param resource $res Raw result
 	 * @return stdClass
 	 */
 	abstract protected function mysqlFetchObject( $res );
 
 	/**
-	 * @param $res ResultWrapper
+	 * @param ResultWrapper|resource $res
 	 * @return array|bool
 	 * @throws DBUnexpectedError
 	 */
@@ -212,22 +253,26 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		// these are the only errors mysql_fetch_array can cause.
 		// See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 		if ( $errno == 2000 || $errno == 2013 ) {
-			throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
+			throw new DBUnexpectedError(
+				$this,
+				'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
+			);
 		}
+
 		return $row;
 	}
 
 	/**
 	 * Fetch a result row as an associative and numeric array
 	 *
-	 * @param $res Raw result
+	 * @param resource $res Raw result
 	 * @return array
 	 */
 	abstract protected function mysqlFetchArray( $res );
 
 	/**
 	 * @throws DBUnexpectedError
-	 * @param $res ResultWrapper
+	 * @param ResultWrapper|resource $res
 	 * @return int
 	 */
 	function numRows( $res ) {
@@ -237,6 +282,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		wfSuppressWarnings();
 		$n = $this->mysqlNumRows( $res );
 		wfRestoreWarnings();
+
 		// Unfortunately, mysql_num_rows does not reset the last errno.
 		// We are not checking for any errors here, since
 		// these are no errors mysql_num_rows can cause.
@@ -248,68 +294,94 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	/**
 	 * Get number of rows in result
 	 *
-	 * @param $res Raw result
+	 * @param resource $res Raw result
 	 * @return int
 	 */
 	abstract protected function mysqlNumRows( $res );
 
 	/**
-	 * @param $res ResultWrapper
+	 * @param ResultWrapper|resource $res
 	 * @return int
 	 */
 	function numFields( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
+
 		return $this->mysqlNumFields( $res );
 	}
 
 	/**
 	 * Get number of fields in result
 	 *
-	 * @param $res Raw result
+	 * @param resource $res Raw result
 	 * @return int
 	 */
 	abstract protected function mysqlNumFields( $res );
 
 	/**
-	 * @param $res ResultWrapper
-	 * @param $n string
+	 * @param ResultWrapper|resource $res
+	 * @param int $n
 	 * @return string
 	 */
 	function fieldName( $res, $n ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
+
 		return $this->mysqlFieldName( $res, $n );
 	}
 
 	/**
 	 * Get the name of the specified field in a result
 	 *
-	 * @param $res Raw result
-	 * @param $n int
+	 * @param ResultWrapper|resource $res
+	 * @param int $n
 	 * @return string
 	 */
 	abstract protected function mysqlFieldName( $res, $n );
 
 	/**
-	 * @param $res ResultWrapper
-	 * @param $row
+	 * mysql_field_type() wrapper
+	 * @param ResultWrapper|resource $res
+	 * @param int $n
+	 * @return string
+	 */
+	public function fieldType( $res, $n ) {
+		if ( $res instanceof ResultWrapper ) {
+			$res = $res->result;
+		}
+
+		return $this->mysqlFieldType( $res, $n );
+	}
+
+	/**
+	 * Get the type of the specified field in a result
+	 *
+	 * @param ResultWrapper|resource $res
+	 * @param int $n
+	 * @return string
+	 */
+	abstract protected function mysqlFieldType( $res, $n );
+
+	/**
+	 * @param ResultWrapper|resource $res
+	 * @param int $row
 	 * @return bool
 	 */
 	function dataSeek( $res, $row ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
+
 		return $this->mysqlDataSeek( $res, $row );
 	}
 
 	/**
 	 * Move internal result pointer
 	 *
-	 * @param $res Raw result
-	 * @param $row int
+	 * @param ResultWrapper|resource $res
+	 * @param int $row
 	 * @return bool
 	 */
 	abstract protected function mysqlDataSeek( $res, $row );
@@ -332,22 +404,23 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		if ( $error ) {
 			$error .= ' (' . $this->mServer . ')';
 		}
+
 		return $error;
 	}
 
 	/**
 	 * Returns the text of the error message from previous MySQL operation
 	 *
-	 * @param $conn Raw connection
+	 * @param resource $conn Raw connection
 	 * @return string
 	 */
 	abstract protected function mysqlError( $conn = null );
 
 	/**
-	 * @param $table string
-	 * @param $uniqueIndexes
-	 * @param $rows array
-	 * @param $fname string
+	 * @param string $table
+	 * @param array $uniqueIndexes
+	 * @param array $rows
+	 * @param string $fname
 	 * @return ResultWrapper
 	 */
 	function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
@@ -359,14 +432,16 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 * Returns estimated count, based on EXPLAIN output
 	 * Takes same arguments as Database::select()
 	 *
-	 * @param $table string|array
-	 * @param $vars string|array
-	 * @param $conds string|array
-	 * @param $fname string
-	 * @param $options string|array
-	 * @return int
+	 * @param string|array $table
+	 * @param string|array $vars
+	 * @param string|array $conds
+	 * @param string $fname
+	 * @param string|array $options
+	 * @return bool|int
 	 */
-	public function estimateRowCount( $table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array() ) {
+	public function estimateRowCount( $table, $vars = '*', $conds = '',
+		$fname = __METHOD__, $options = array()
+	) {
 		$options['EXPLAIN'] = true;
 		$res = $this->select( $table, $vars, $conds, $fname, $options );
 		if ( $res === false ) {
@@ -380,12 +455,13 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		foreach ( $res as $plan ) {
 			$rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 		}
+
 		return $rows;
 	}
 
 	/**
-	 * @param $table string
-	 * @param $field string
+	 * @param string $table
+	 * @param string $field
 	 * @return bool|MySQLField
 	 */
 	function fieldInfo( $table, $field ) {
@@ -401,14 +477,15 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 				return new MySQLField( $meta );
 			}
 		}
+
 		return false;
 	}
 
 	/**
 	 * Get column information from a result
 	 *
-	 * @param $res Raw result
-	 * @param $n int
+	 * @param resource $res Raw result
+	 * @param int $n
 	 * @return stdClass
 	 */
 	abstract protected function mysqlFetchField( $res, $n );
@@ -417,9 +494,9 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 * Get information about an index into an object
 	 * Returns false if the index does not exist
 	 *
-	 * @param $table string
-	 * @param $index string
-	 * @param $fname string
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return bool|array|null False or null on failure
 	 */
 	function indexInfo( $table, $index, $fname = __METHOD__ ) {
@@ -443,12 +520,12 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 				$result[] = $row;
 			}
 		}
+
 		return empty( $result ) ? false : $result;
 	}
 
 	/**
-	 * @param $s string
-	 *
+	 * @param string $s
 	 * @return string
 	 */
 	function strencode( $s ) {
@@ -458,24 +535,24 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 			$this->ping();
 			$sQuoted = $this->mysqlRealEscapeString( $s );
 		}
+
 		return $sQuoted;
 	}
 
 	/**
 	 * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
 	 *
-	 * @param $s string
-	 *
+	 * @param string $s
 	 * @return string
 	 */
 	public function addIdentifierQuotes( $s ) {
 		// Characters in the range \u0001-\uFFFF are valid in a quoted identifier
 		// Remove NUL bytes and escape backticks by doubling
-		return '`' . str_replace( array( "\0", '`' ), array( '', '``' ), $s )  . '`';
+		return '`' . str_replace( array( "\0", '`' ), array( '', '``' ), $s ) . '`';
 	}
 
 	/**
-	 * @param $name string
+	 * @param string $name
 	 * @return bool
 	 */
 	public function isQuotedIdentifier( $name ) {
@@ -495,6 +572,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		$this->mOpened = false;
 		$this->mConn = false;
 		$this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
+
 		return true;
 	}
 
@@ -506,6 +584,24 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	abstract protected function mysqlPing();
 
 	/**
+	 * Set lag time in seconds for a fake slave
+	 *
+	 * @param int $lag
+	 */
+	public function setFakeSlaveLag( $lag ) {
+		$this->mFakeSlaveLag = $lag;
+	}
+
+	/**
+	 * Make this connection a fake master
+	 *
+	 * @param bool $enabled
+	 */
+	public function setFakeMaster( $enabled = true ) {
+		$this->mFakeMaster = $enabled;
+	}
+
+	/**
 	 * Returns slave lag.
 	 *
 	 * This will do a SHOW SLAVE STATUS
@@ -515,6 +611,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	function getLag() {
 		if ( !is_null( $this->mFakeSlaveLag ) ) {
 			wfDebug( "getLag: fake slave lagged {$this->mFakeSlaveLag} seconds\n" );
+
 			return $this->mFakeSlaveLag;
 		}
 
@@ -541,52 +638,14 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	}
 
 	/**
-	 * @deprecated in 1.19, use getLagFromSlaveStatus
-	 *
-	 * @return bool|int
-	 */
-	function getLagFromProcesslist() {
-		wfDeprecated( __METHOD__, '1.19' );
-		$res = $this->query( 'SHOW PROCESSLIST', __METHOD__ );
-		if ( !$res ) {
-			return false;
-		}
-		# Find slave SQL thread
-		foreach ( $res as $row ) {
-			/* This should work for most situations - when default db
-			 * for thread is not specified, it had no events executed,
-			 * and therefore it doesn't know yet how lagged it is.
-			 *
-			 * Relay log I/O thread does not select databases.
-			 */
-			if ( $row->User == 'system user' &&
-				$row->State != 'Waiting for master to send event' &&
-				$row->State != 'Connecting to master' &&
-				$row->State != 'Queueing master event to the relay log' &&
-				$row->State != 'Waiting for master update' &&
-				$row->State != 'Requesting binlog dump' &&
-				$row->State != 'Waiting to reconnect after a failed master event read' &&
-				$row->State != 'Reconnecting after a failed master event read' &&
-				$row->State != 'Registering slave on master'
-				) {
-				# This is it, return the time (except -ve)
-				if ( $row->Time > 0x7fffffff ) {
-					return false;
-				} else {
-					return $row->Time;
-				}
-			}
-		}
-		return false;
-	}
-
-	/**
 	 * Wait for the slave to catch up to a given master position.
-	 * @TODO: return values for this and base class are rubbish
+	 * @todo Return values for this and base class are rubbish
 	 *
-	 * @param $pos DBMasterPos object
-	 * @param $timeout Integer: the maximum number of seconds to wait for synchronisation
-	 * @return bool|string
+	 * @param DBMasterPos|MySQLMasterPos $pos
+	 * @param int $timeout The maximum number of seconds to wait for synchronisation
+	 * @return int Zero if the slave was past that position already,
+	 *   greater than zero if we waited for some period of time, less than
+	 *   zero if we timed out.
 	 */
 	function masterPosWait( DBMasterPos $pos, $timeout ) {
 		if ( $this->lastKnownSlavePos && $this->lastKnownSlavePos->hasReached( $pos ) ) {
@@ -598,9 +657,25 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		$this->commit( __METHOD__, 'flush' );
 
 		if ( !is_null( $this->mFakeSlaveLag ) ) {
-			$status = parent::masterPosWait( $pos, $timeout );
-			wfProfileOut( __METHOD__ );
-			return $status;
+			$wait = intval( ( $pos->pos - microtime( true ) + $this->mFakeSlaveLag ) * 1e6 );
+
+			if ( $wait > $timeout * 1e6 ) {
+				wfDebug( "Fake slave timed out waiting for $pos ($wait us)\n" );
+				wfProfileOut( __METHOD__ );
+
+				return -1;
+			} elseif ( $wait > 0 ) {
+				wfDebug( "Fake slave waiting $wait us\n" );
+				usleep( $wait );
+				wfProfileOut( __METHOD__ );
+
+				return 1;
+			} else {
+				wfDebug( "Fake slave up to date ($wait us)\n" );
+				wfProfileOut( __METHOD__ );
+
+				return 0;
+			}
 		}
 
 		# Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
@@ -618,6 +693,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		}
 
 		wfProfileOut( __METHOD__ );
+
 		return $status;
 	}
 
@@ -628,14 +704,20 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 */
 	function getSlavePos() {
 		if ( !is_null( $this->mFakeSlaveLag ) ) {
-			return parent::getSlavePos();
+			$pos = new MySQLMasterPos( 'fake', microtime( true ) - $this->mFakeSlaveLag );
+			wfDebug( __METHOD__ . ": fake slave pos = $pos\n" );
+
+			return $pos;
 		}
 
 		$res = $this->query( 'SHOW SLAVE STATUS', 'DatabaseBase::getSlavePos' );
 		$row = $this->fetchObject( $res );
 
 		if ( $row ) {
-			$pos = isset( $row->Exec_master_log_pos ) ? $row->Exec_master_log_pos : $row->Exec_Master_Log_Pos;
+			$pos = isset( $row->Exec_master_log_pos )
+				? $row->Exec_master_log_pos
+				: $row->Exec_Master_Log_Pos;
+
 			return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos );
 		} else {
 			return false;
@@ -649,7 +731,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 */
 	function getMasterPos() {
 		if ( $this->mFakeMaster ) {
-			return parent::getMasterPos();
+			return new MySQLMasterPos( 'fake', microtime( true ) );
 		}
 
 		$res = $this->query( 'SHOW MASTER STATUS', 'DatabaseBase::getMasterPos' );
@@ -663,7 +745,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	}
 
 	/**
-	 * @param $index
+	 * @param string $index
 	 * @return string
 	 */
 	function useIndexClause( $index ) {
@@ -681,18 +763,22 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 * @return string
 	 */
 	public function getSoftwareLink() {
+		// MariaDB includes its name in its version string (sent when the connection is opened),
+		// and this is how MariaDB's version of the mysql command-line client identifies MariaDB
+		// servers (see the mariadb_connection() function in libmysql/libmysql.c).
 		$version = $this->getServerVersion();
-		if ( strpos( $version, 'MariaDB' ) !== false ) {
+		if ( strpos( $version, 'MariaDB' ) !== false || strpos( $version, '-maria-' ) !== false ) {
 			return '[{{int:version-db-mariadb-url}} MariaDB]';
-		} elseif ( strpos( $version, 'percona' ) !== false ) {
-			return '[{{int:version-db-percona-url}} Percona Server]';
-		} else {
-			return '[{{int:version-db-mysql-url}} MySQL]';
 		}
+
+		// Percona Server's version suffix is not very distinctive, and @@version_comment
+		// doesn't give the necessary info for source builds, so assume the server is MySQL.
+		// (Even Percona's version of mysql doesn't try to make the distinction.)
+		return '[{{int:version-db-mysql-url}} MySQL]';
 	}
 
 	/**
-	 * @param $options array
+	 * @param array $options
 	 */
 	public function setSessionOptions( array $options ) {
 		if ( isset( $options['connTimeout'] ) ) {
@@ -702,34 +788,41 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		}
 	}
 
+	/**
+	 * @param string $sql
+	 * @param string $newLine
+	 * @return bool
+	 */
 	public function streamStatementEnd( &$sql, &$newLine ) {
 		if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
 			preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
 			$this->delimiter = $m[1];
 			$newLine = '';
 		}
+
 		return parent::streamStatementEnd( $sql, $newLine );
 	}
 
 	/**
 	 * Check to see if a named lock is available. This is non-blocking.
 	 *
-	 * @param string $lockName name of lock to poll
-	 * @param string $method name of method calling us
-	 * @return Boolean
+	 * @param string $lockName Name of lock to poll
+	 * @param string $method Name of method calling us
+	 * @return bool
 	 * @since 1.20
 	 */
 	public function lockIsFree( $lockName, $method ) {
 		$lockName = $this->addQuotes( $lockName );
 		$result = $this->query( "SELECT IS_FREE_LOCK($lockName) AS lockstatus", $method );
 		$row = $this->fetchObject( $result );
+
 		return ( $row->lockstatus == 1 );
 	}
 
 	/**
-	 * @param $lockName string
-	 * @param $method string
-	 * @param $timeout int
+	 * @param string $lockName
+	 * @param string $method
+	 * @param int $timeout
 	 * @return bool
 	 */
 	public function lock( $lockName, $method, $timeout = 5 ) {
@@ -741,28 +834,31 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 			return true;
 		} else {
 			wfDebug( __METHOD__ . " failed to acquire lock\n" );
+
 			return false;
 		}
 	}
 
 	/**
-	 * FROM MYSQL DOCS: http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
-	 * @param $lockName string
-	 * @param $method string
+	 * FROM MYSQL DOCS:
+	 * http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
+	 * @param string $lockName
+	 * @param string $method
 	 * @return bool
 	 */
 	public function unlock( $lockName, $method ) {
 		$lockName = $this->addQuotes( $lockName );
 		$result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 		$row = $this->fetchObject( $result );
+
 		return ( $row->lockstatus == 1 );
 	}
 
 	/**
-	 * @param $read array
-	 * @param $write array
-	 * @param $method string
-	 * @param $lowPriority bool
+	 * @param array $read
+	 * @param array $write
+	 * @param string $method
+	 * @param bool $lowPriority
 	 * @return bool
 	 */
 	public function lockTables( $read, $write, $method, $lowPriority = true ) {
@@ -770,8 +866,8 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 
 		foreach ( $write as $table ) {
 			$tbl = $this->tableName( $table ) .
-					( $lowPriority ? ' LOW_PRIORITY' : '' ) .
-					' WRITE';
+				( $lowPriority ? ' LOW_PRIORITY' : '' ) .
+				' WRITE';
 			$items[] = $tbl;
 		}
 		foreach ( $read as $table ) {
@@ -779,15 +875,17 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 		}
 		$sql = "LOCK TABLES " . implode( ',', $items );
 		$this->query( $sql, $method );
+
 		return true;
 	}
 
 	/**
-	 * @param $method string
+	 * @param string $method
 	 * @return bool
 	 */
 	public function unlockTables( $method ) {
 		$this->query( "UNLOCK TABLES", $method );
+
 		return true;
 	}
 
@@ -795,7 +893,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 * Get search engine class. All subclasses of this
 	 * need to implement this if they wish to use searching.
 	 *
-	 * @return String
+	 * @return string
 	 */
 	public function getSearchEngine() {
 		return 'SearchMySQL';
@@ -803,7 +901,6 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 
 	/**
 	 * @param bool $value
-	 * @return mixed
 	 */
 	public function setBigSelects( $value = true ) {
 		if ( $value === 'default' ) {
@@ -822,12 +919,12 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 
 	/**
 	 * DELETE where the condition is a join. MySql uses multi-table deletes.
-	 * @param $delTable string
-	 * @param $joinTable string
-	 * @param $delVar string
-	 * @param $joinVar string
-	 * @param $conds array|string
-	 * @param bool|string $fname bool
+	 * @param string $delTable
+	 * @param string $joinTable
+	 * @param string $delVar
+	 * @param string $joinVar
+	 * @param array|string $conds
+	 * @param bool|string $fname
 	 * @throws DBUnexpectedError
 	 * @return bool|ResultWrapper
 	 */
@@ -853,16 +950,18 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 * @param array $uniqueIndexes
 	 * @param array $set
 	 * @param string $fname
-	 * @param array $options
 	 * @return bool
 	 */
-	public function upsert(
-		$table, array $rows, array $uniqueIndexes, array $set, $fname = __METHOD__
+	public function upsert( $table, array $rows, array $uniqueIndexes,
+		array $set, $fname = __METHOD__
 	) {
 		if ( !count( $rows ) ) {
 			return true; // nothing to do
 		}
-		$rows = is_array( reset( $rows ) ) ? $rows : array( $rows );
+
+		if ( !is_array( reset( $rows ) ) ) {
+			$rows = array( $rows );
+		}
 
 		$table = $this->tableName( $table );
 		$columns = array_keys( $rows[0] );
@@ -885,6 +984,7 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	 */
 	function getServerUptime() {
 		$vars = $this->getMysqlStatus( 'Uptime' );
+
 		return (int)$vars['Uptime'];
 	}
 
@@ -927,24 +1027,26 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	}
 
 	/**
-	 * @param $oldName
-	 * @param $newName
-	 * @param $temporary bool
-	 * @param $fname string
+	 * @param string $oldName
+	 * @param string $newName
+	 * @param bool $temporary
+	 * @param string $fname
+	 * @return bool
 	 */
 	function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
 		$tmp = $temporary ? 'TEMPORARY ' : '';
 		$newName = $this->addIdentifierQuotes( $newName );
 		$oldName = $this->addIdentifierQuotes( $oldName );
 		$query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
-		$this->query( $query, $fname );
+
+		return $this->query( $query, $fname );
 	}
 
 	/**
 	 * List all tables on the database
 	 *
 	 * @param string $prefix Only show tables with this prefix, e.g. mw_
-	 * @param string $fname calling function name
+	 * @param string $fname Calling function name
 	 * @return array
 	 */
 	function listTables( $prefix = null, $fname = __METHOD__ ) {
@@ -965,14 +1067,15 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	}
 
 	/**
-	 * @param $tableName
-	 * @param $fName string
+	 * @param string $tableName
+	 * @param string $fName
 	 * @return bool|ResultWrapper
 	 */
 	public function dropTable( $tableName, $fName = __METHOD__ ) {
 		if ( !$this->tableExists( $tableName, $fName ) ) {
 			return false;
 		}
+
 		return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
 	}
 
@@ -982,14 +1085,19 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	protected function getDefaultSchemaVars() {
 		$vars = parent::getDefaultSchemaVars();
 		$vars['wgDBTableOptions'] = str_replace( 'TYPE', 'ENGINE', $GLOBALS['wgDBTableOptions'] );
-		$vars['wgDBTableOptions'] = str_replace( 'CHARSET=mysql4', 'CHARSET=binary', $vars['wgDBTableOptions'] );
+		$vars['wgDBTableOptions'] = str_replace(
+			'CHARSET=mysql4',
+			'CHARSET=binary',
+			$vars['wgDBTableOptions']
+		);
+
 		return $vars;
 	}
 
 	/**
 	 * Get status information from SHOW STATUS in an associative array
 	 *
-	 * @param $which string
+	 * @param string $which
 	 * @return array
 	 */
 	function getMysqlStatus( $which = "%" ) {
@@ -1006,9 +1114,9 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 	/**
 	 * Lists VIEWs in the database
 	 *
-	 * @param string $prefix   Only show VIEWs with this prefix, eg.
+	 * @param string $prefix Only show VIEWs with this prefix, eg.
 	 * unit_test_, or $wgDBprefix. Default: null, would return all views.
-	 * @param string $fname    Name of calling function
+	 * @param string $fname Name of calling function
 	 * @return array
 	 * @since 1.22
 	 */
@@ -1022,12 +1130,12 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 			// Query for the VIEWS
 			$result = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
 			$this->allViews = array();
-			while ( ($row = $this->fetchRow($result)) !== false ) {
+			while ( ( $row = $this->fetchRow( $result ) ) !== false ) {
 				array_push( $this->allViews, $row[$propertyName] );
 			}
 		}
 
-		if ( is_null($prefix) || $prefix === '' ) {
+		if ( is_null( $prefix ) || $prefix === '' ) {
 			return $this->allViews;
 		}
 
@@ -1038,24 +1146,23 @@ abstract class DatabaseMysqlBase extends DatabaseBase {
 				array_push( $filteredViews, $viewName );
 			}
 		}
+
 		return $filteredViews;
 	}
 
 	/**
 	 * Differentiates between a TABLE and a VIEW.
 	 *
-	 * @param $name string: Name of the TABLE/VIEW to test
+	 * @param string $name Name of the TABLE/VIEW to test
+	 * @param string $prefix
 	 * @return bool
 	 * @since 1.22
 	 */
 	public function isView( $name, $prefix = null ) {
 		return in_array( $name, $this->listViews( $prefix ) );
 	}
-
 }
 
-
-
 /**
  * Utility class.
  * @ingroup Database
@@ -1130,7 +1237,11 @@ class MySQLField implements Field {
 }
 
 class MySQLMasterPos implements DBMasterPos {
-	var $file, $pos;
+	/** @var string */
+	public $file;
+
+	/** @var int Timestamp */
+	public $pos;
 
 	function __construct( $file, $pos ) {
 		$this->file = $file;
@@ -1143,19 +1254,21 @@ class MySQLMasterPos implements DBMasterPos {
 	}
 
 	/**
-	 * @return array|false (int, int)
+	 * @return array|bool (int, int)
 	 */
 	protected function getCoordinates() {
 		$m = array();
 		if ( preg_match( '!\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
 			return array( (int)$m[1], (int)$m[2] );
 		}
+
 		return false;
 	}
 
 	function hasReached( MySQLMasterPos $pos ) {
 		$thisPos = $this->getCoordinates();
 		$thatPos = $pos->getCoordinates();
+
 		return ( $thisPos && $thatPos && $thisPos >= $thatPos );
 	}
 }
diff --git a/includes/db/DatabaseMysqli.php b/includes/db/DatabaseMysqli.php
index 0ec54314..a03c9aaf 100644
--- a/includes/db/DatabaseMysqli.php
+++ b/includes/db/DatabaseMysqli.php
@@ -29,9 +29,8 @@
  * @see Database
  */
 class DatabaseMysqli extends DatabaseMysqlBase {
-
 	/**
-	 * @param $sql string
+	 * @param string $sql
 	 * @return resource
 	 */
 	protected function doQuery( $sql ) {
@@ -40,10 +39,17 @@ class DatabaseMysqli extends DatabaseMysqlBase {
 		} else {
 			$ret = $this->mConn->query( $sql, MYSQLI_USE_RESULT );
 		}
+
 		return $ret;
 	}
 
+	/**
+	 * @param string $realServer
+	 * @return bool|mysqli
+	 * @throws DBConnectionError
+	 */
 	protected function mysqlConnect( $realServer ) {
+		global $wgDBmysql5;
 		# Fail now
 		# Otherwise we get a suppressed fatal error, which is very hard to track down
 		if ( !function_exists( 'mysqli_init' ) ) {
@@ -52,14 +58,22 @@ class DatabaseMysqli extends DatabaseMysqlBase {
 		}
 
 		// Other than mysql_connect, mysqli_real_connect expects an explicit port
-		// parameter. So we need to parse the port out of $realServer
+		// and socket parameters. So we need to parse the port and socket out of
+		// $realServer
 		$port = null;
+		$socket = null;
 		$hostAndPort = IP::splitHostAndPort( $realServer );
 		if ( $hostAndPort ) {
 			$realServer = $hostAndPort[0];
 			if ( $hostAndPort[1] ) {
 				$port = $hostAndPort[1];
 			}
+		} elseif ( substr_count( $realServer, ':' ) == 1 ) {
+			// If we have a colon and something that's not a port number
+			// inside the hostname, assume it's the socket location
+			$hostAndSocket = explode( ':', $realServer );
+			$realServer = $hostAndSocket[0];
+			$socket = $hostAndSocket[1];
 		}
 
 		$connFlags = 0;
@@ -74,22 +88,41 @@ class DatabaseMysqli extends DatabaseMysqlBase {
 		}
 
 		$mysqli = mysqli_init();
-		$numAttempts = 2;
+		if ( $wgDBmysql5 ) {
+			// Tell the server we're communicating with it in UTF-8.
+			// This may engage various charset conversions.
+			$mysqli->options( MYSQLI_SET_CHARSET_NAME, 'utf8' );
+		} else {
+			$mysqli->options( MYSQLI_SET_CHARSET_NAME, 'binary' );
+		}
+		$mysqli->options( MYSQLI_OPT_CONNECT_TIMEOUT, 3 );
 
-		for ( $i = 0; $i < $numAttempts; $i++ ) {
-			if ( $i > 1 ) {
-				usleep( 1000 );
-			}
-			if ( $mysqli->real_connect( $realServer, $this->mUser,
-				$this->mPassword, $this->mDBname, $port, null, $connFlags ) )
-			{
-				return $mysqli;
-			}
+		if ( $mysqli->real_connect( $realServer, $this->mUser,
+			$this->mPassword, $this->mDBname, $port, $socket, $connFlags )
+		) {
+			return $mysqli;
 		}
 
 		return false;
 	}
 
+	protected function connectInitCharset() {
+		// already done in mysqlConnect()
+		return true;
+	}
+
+	/**
+	 * @param string $charset
+	 * @return bool
+	 */
+	protected function mysqlSetCharset( $charset ) {
+		if ( method_exists( $this->mConn, 'set_charset' ) ) {
+			return $this->mConn->set_charset( $charset );
+		} else {
+			return $this->query( 'SET NAMES ' . $charset, __METHOD__ );
+		}
+	}
+
 	/**
 	 * @return bool
 	 */
@@ -123,11 +156,12 @@ class DatabaseMysqli extends DatabaseMysqlBase {
 	}
 
 	/**
-	 * @param $db
+	 * @param string $db
 	 * @return bool
 	 */
 	function selectDB( $db ) {
 		$this->mDBname = $db;
+
 		return $this->mConn->select_db( $db );
 	}
 
@@ -138,35 +172,63 @@ class DatabaseMysqli extends DatabaseMysqlBase {
 		return $this->mConn->server_info;
 	}
 
+	/**
+	 * @param mysqli $res
+	 * @return bool
+	 */
 	protected function mysqlFreeResult( $res ) {
 		$res->free_result();
+
 		return true;
 	}
 
+	/**
+	 * @param mysqli $res
+	 * @return bool
+	 */
 	protected function mysqlFetchObject( $res ) {
 		$object = $res->fetch_object();
 		if ( $object === null ) {
 			return false;
 		}
+
 		return $object;
 	}
 
+	/**
+	 * @param mysqli $res
+	 * @return bool
+	 */
 	protected function mysqlFetchArray( $res ) {
 		$array = $res->fetch_array();
 		if ( $array === null ) {
 			return false;
 		}
+
 		return $array;
 	}
 
+	/**
+	 * @param mysqli $res
+	 * @return mixed
+	 */
 	protected function mysqlNumRows( $res ) {
 		return $res->num_rows;
 	}
 
+	/**
+	 * @param mysqli $res
+	 * @return mixed
+	 */
 	protected function mysqlNumFields( $res ) {
 		return $res->field_count;
 	}
 
+	/**
+	 * @param mysqli $res
+	 * @param int $n
+	 * @return mixed
+	 */
 	protected function mysqlFetchField( $res, $n ) {
 		$field = $res->fetch_field_direct( $n );
 		$field->not_null = $field->flags & MYSQLI_NOT_NULL_FLAG;
@@ -174,26 +236,58 @@ class DatabaseMysqli extends DatabaseMysqlBase {
 		$field->unique_key = $field->flags & MYSQLI_UNIQUE_KEY_FLAG;
 		$field->multiple_key = $field->flags & MYSQLI_MULTIPLE_KEY_FLAG;
 		$field->binary = $field->flags & MYSQLI_BINARY_FLAG;
+
 		return $field;
 	}
 
+	/**
+	 * @param resource|ResultWrapper $res
+	 * @param int $n
+	 * @return mixed
+	 */
 	protected function mysqlFieldName( $res, $n ) {
 		$field = $res->fetch_field_direct( $n );
+
 		return $field->name;
 	}
 
+	/**
+	 * @param resource|ResultWrapper $res
+	 * @param int $n
+	 * @return mixed
+	 */
+	protected function mysqlFieldType( $res, $n ) {
+		$field = $res->fetch_field_direct( $n );
+
+		return $field->type;
+	}
+
+	/**
+	 * @param resource|ResultWrapper $res
+	 * @param int $row
+	 * @return mixed
+	 */
 	protected function mysqlDataSeek( $res, $row ) {
 		return $res->data_seek( $row );
 	}
 
+	/**
+	 * @param mysqli $conn Optional connection object
+	 * @return string
+	 */
 	protected function mysqlError( $conn = null ) {
-		if ($conn === null) {
+		if ( $conn === null ) {
 			return mysqli_connect_error();
 		} else {
 			return $conn->error;
 		}
 	}
 
+	/**
+	 * Escapes special characters in a string for use in an SQL statement
+	 * @param string $s
+	 * @return string
+	 */
 	protected function mysqlRealEscapeString( $s ) {
 		return $this->mConn->real_escape_string( $s );
 	}
@@ -202,4 +296,18 @@ class DatabaseMysqli extends DatabaseMysqlBase {
 		return $this->mConn->ping();
 	}
 
+	/**
+	 * Give an id for the connection
+	 *
+	 * mysql driver used resource id, but mysqli objects cannot be cast to string.
+	 * @return string
+	 */
+	public function __toString() {
+		if ( $this->mConn instanceof Mysqli ) {
+			return (string)$this->mConn->thread_id;
+		} else {
+			// mConn might be false or something.
+			return (string)$this->mConn;
+		}
+	}
 }
diff --git a/includes/db/DatabaseOracle.php b/includes/db/DatabaseOracle.php
index 9009b328..f031f780 100644
--- a/includes/db/DatabaseOracle.php
+++ b/includes/db/DatabaseOracle.php
@@ -50,17 +50,19 @@ class ORAResult {
 	}
 
 	/**
-	 * @param $db DatabaseBase
-	 * @param $stmt
+	 * @param DatabaseBase $db
+	 * @param resource $stmt A valid OCI statement identifier
 	 * @param bool $unique
 	 */
 	function __construct( &$db, $stmt, $unique = false ) {
 		$this->db =& $db;
 
-		if ( ( $this->nrows = oci_fetch_all( $stmt, $this->rows, 0, - 1, OCI_FETCHSTATEMENT_BY_ROW | OCI_NUM ) ) === false ) {
+		$this->nrows = oci_fetch_all( $stmt, $this->rows, 0, -1, OCI_FETCHSTATEMENT_BY_ROW | OCI_NUM );
+		if ( $this->nrows === false ) {
 			$e = oci_error( $stmt );
 			$db->reportQueryError( $e['message'], $e['code'], '', __METHOD__ );
 			$this->free();
+
 			return;
 		}
 
@@ -121,6 +123,7 @@ class ORAResult {
 			$ret[$lc] = $v;
 			$ret[$k] = $v;
 		}
+
 		return $ret;
 	}
 }
@@ -183,25 +186,49 @@ class ORAField implements Field {
  * @ingroup Database
  */
 class DatabaseOracle extends DatabaseBase {
-	var $mInsertId = null;
-	var $mLastResult = null;
-	var $lastResult = null;
-	var $cursor = 0;
-	var $mAffectedRows;
+	/** @var resource */
+	protected $mLastResult = null;
+
+	/** @var int The number of rows affected as an integer */
+	protected $mAffectedRows;
 
-	var $ignore_DUP_VAL_ON_INDEX = false;
-	var $sequenceData = null;
+	/** @var int */
+	private $mInsertId = null;
 
-	var $defaultCharset = 'AL32UTF8';
+	/** @var bool */
+	private $ignoreDupValOnIndex = false;
 
-	var $mFieldInfoCache = array();
+	/** @var bool|array */
+	private $sequenceData = null;
 
-	function __construct( $server = false, $user = false, $password = false, $dbName = false,
-		$flags = 0, $tablePrefix = 'get from global' )
-	{
+	/** @var string Character set for Oracle database */
+	private $defaultCharset = 'AL32UTF8';
+
+	/** @var array */
+	private $mFieldInfoCache = array();
+
+	function __construct( $p = null ) {
 		global $wgDBprefix;
-		$tablePrefix = $tablePrefix == 'get from global' ? strtoupper( $wgDBprefix ) : strtoupper( $tablePrefix );
-		parent::__construct( $server, $user, $password, $dbName, $flags, $tablePrefix );
+
+		if ( !is_array( $p ) ) { // legacy calling pattern
+			wfDeprecated( __METHOD__ . " method called without parameter array.", "1.22" );
+			$args = func_get_args();
+			$p = array(
+				'host' => isset( $args[0] ) ? $args[0] : false,
+				'user' => isset( $args[1] ) ? $args[1] : false,
+				'password' => isset( $args[2] ) ? $args[2] : false,
+				'dbname' => isset( $args[3] ) ? $args[3] : false,
+				'flags' => isset( $args[4] ) ? $args[4] : 0,
+				'tablePrefix' => isset( $args[5] ) ? $args[5] : 'get from global',
+				'schema' => 'get from global',
+				'foreign' => isset( $args[6] ) ? $args[6] : false
+			);
+		}
+		if ( $p['tablePrefix'] == 'get from global' ) {
+			$p['tablePrefix'] = $wgDBprefix;
+		}
+		$p['tablePrefix'] = strtoupper( $p['tablePrefix'] );
+		parent::__construct( $p );
 		wfRunHooks( 'DatabaseOraclePostInit', array( $this ) );
 	}
 
@@ -220,21 +247,27 @@ class DatabaseOracle extends DatabaseBase {
 	function cascadingDeletes() {
 		return true;
 	}
+
 	function cleanupTriggers() {
 		return true;
 	}
+
 	function strictIPs() {
 		return true;
 	}
+
 	function realTimestamps() {
 		return true;
 	}
+
 	function implicitGroupby() {
 		return false;
 	}
+
 	function implicitOrderby() {
 		return false;
 	}
+
 	function searchableIPs() {
 		return true;
 	}
@@ -251,7 +284,11 @@ class DatabaseOracle extends DatabaseBase {
 	function open( $server, $user, $password, $dbName ) {
 		global $wgDBOracleDRCP;
 		if ( !function_exists( 'oci_connect' ) ) {
-			throw new DBConnectionError( $this, "Oracle functions missing, have you compiled PHP with the --with-oci8 option?\n (Note: if you recently installed PHP, you may need to restart your webserver and database)\n" );
+			throw new DBConnectionError(
+				$this,
+				"Oracle functions missing, have you compiled PHP with the --with-oci8 option?\n " .
+					"(Note: if you recently installed PHP, you may need to restart your webserver\n " .
+					"and database)\n" );
 		}
 
 		$this->close();
@@ -274,7 +311,7 @@ class DatabaseOracle extends DatabaseBase {
 		}
 
 		if ( !strlen( $user ) ) { # e.g. the class is being loaded
-			return;
+			return null;
 		}
 
 		if ( $wgDBOracleDRCP ) {
@@ -285,11 +322,29 @@ class DatabaseOracle extends DatabaseBase {
 
 		wfSuppressWarnings();
 		if ( $this->mFlags & DBO_PERSISTENT ) {
-			$this->mConn = oci_pconnect( $this->mUser, $this->mPassword, $this->mServer, $this->defaultCharset, $session_mode );
+			$this->mConn = oci_pconnect(
+				$this->mUser,
+				$this->mPassword,
+				$this->mServer,
+				$this->defaultCharset,
+				$session_mode
+			);
 		} elseif ( $this->mFlags & DBO_DEFAULT ) {
-			$this->mConn = oci_new_connect( $this->mUser, $this->mPassword, $this->mServer, $this->defaultCharset, $session_mode );
+			$this->mConn = oci_new_connect(
+				$this->mUser,
+				$this->mPassword,
+				$this->mServer,
+				$this->defaultCharset,
+				$session_mode
+			);
 		} else {
-			$this->mConn = oci_connect( $this->mUser, $this->mPassword, $this->mServer, $this->defaultCharset, $session_mode );
+			$this->mConn = oci_connect(
+				$this->mUser,
+				$this->mPassword,
+				$this->mServer,
+				$this->defaultCharset,
+				$session_mode
+			);
 		}
 		wfRestoreWarnings();
 
@@ -308,6 +363,7 @@ class DatabaseOracle extends DatabaseBase {
 		$this->doQuery( 'ALTER SESSION SET NLS_TIMESTAMP_FORMAT=\'DD-MM-YYYY HH24:MI:SS.FF6\'' );
 		$this->doQuery( 'ALTER SESSION SET NLS_TIMESTAMP_TZ_FORMAT=\'DD-MM-YYYY HH24:MI:SS.FF6\'' );
 		$this->doQuery( 'ALTER SESSION SET NLS_NUMERIC_CHARACTERS=\'.,\'' );
+
 		return $this->mConn;
 	}
 
@@ -343,20 +399,28 @@ class DatabaseOracle extends DatabaseBase {
 		// you have to select data from plan table after explain
 		$explain_id = MWTimestamp::getLocalInstance()->format( 'dmYHis' );
 
-		$sql = preg_replace( '/^EXPLAIN /', 'EXPLAIN PLAN SET STATEMENT_ID = \'' . $explain_id . '\' FOR', $sql, 1, $explain_count );
+		$sql = preg_replace(
+			'/^EXPLAIN /',
+			'EXPLAIN PLAN SET STATEMENT_ID = \'' . $explain_id . '\' FOR',
+			$sql,
+			1,
+			$explain_count
+		);
 
 		wfSuppressWarnings();
 
 		if ( ( $this->mLastResult = $stmt = oci_parse( $this->mConn, $sql ) ) === false ) {
 			$e = oci_error( $this->mConn );
 			$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 			return false;
 		}
 
 		if ( !oci_execute( $stmt, $this->execFlags() ) ) {
 			$e = oci_error( $stmt );
-			if ( !$this->ignore_DUP_VAL_ON_INDEX || $e['code'] != '1' ) {
+			if ( !$this->ignoreDupValOnIndex || $e['code'] != '1' ) {
 				$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 				return false;
 			}
 		}
@@ -364,11 +428,13 @@ class DatabaseOracle extends DatabaseBase {
 		wfRestoreWarnings();
 
 		if ( $explain_count > 0 ) {
-			return $this->doQuery( 'SELECT id, cardinality "ROWS" FROM plan_table WHERE statement_id = \'' . $explain_id . '\'' );
+			return $this->doQuery( 'SELECT id, cardinality "ROWS" FROM plan_table ' .
+				'WHERE statement_id = \'' . $explain_id . '\'' );
 		} elseif ( oci_statement_type( $stmt ) == 'SELECT' ) {
 			return new ORAResult( $this, $stmt, $union_unique );
 		} else {
 			$this->mAffectedRows = oci_num_rows( $stmt );
+
 			return true;
 		}
 	}
@@ -377,6 +443,10 @@ class DatabaseOracle extends DatabaseBase {
 		return $this->query( $sql, $fname, true );
 	}
 
+	/**
+	 * Frees resources associated with the LOB descriptor
+	 * @param ResultWrapper|resource $res
+	 */
 	function freeResult( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
@@ -385,6 +455,10 @@ class DatabaseOracle extends DatabaseBase {
 		$res->free();
 	}
 
+	/**
+	 * @param ResultWrapper|stdClass $res
+	 * @return mixed
+	 */
 	function fetchObject( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
@@ -423,12 +497,16 @@ class DatabaseOracle extends DatabaseBase {
 
 	/**
 	 * This must be called after nextSequenceVal
-	 * @return null
+	 * @return null|int
 	 */
 	function insertId() {
 		return $this->mInsertId;
 	}
 
+	/**
+	 * @param mixed $res
+	 * @param int $row
+	 */
 	function dataSeek( $res, $row ) {
 		if ( $res instanceof ORAResult ) {
 			$res->seek( $row );
@@ -443,6 +521,7 @@ class DatabaseOracle extends DatabaseBase {
 		} else {
 			$e = oci_error( $this->mConn );
 		}
+
 		return $e['message'];
 	}
 
@@ -452,6 +531,7 @@ class DatabaseOracle extends DatabaseBase {
 		} else {
 			$e = oci_error( $this->mConn );
 		}
+
 		return $e['code'];
 	}
 
@@ -462,6 +542,9 @@ class DatabaseOracle extends DatabaseBase {
 	/**
 	 * Returns information about an index
 	 * If errors are explicitly ignored, returns NULL on failure
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return bool
 	 */
 	function indexInfo( $table, $index, $fname = __METHOD__ ) {
@@ -482,7 +565,7 @@ class DatabaseOracle extends DatabaseBase {
 		}
 
 		if ( in_array( 'IGNORE', $options ) ) {
-			$this->ignore_DUP_VAL_ON_INDEX = true;
+			$this->ignoreDupValOnIndex = true;
 		}
 
 		if ( !is_array( reset( $a ) ) ) {
@@ -495,7 +578,7 @@ class DatabaseOracle extends DatabaseBase {
 		$retVal = true;
 
 		if ( in_array( 'IGNORE', $options ) ) {
-			$this->ignore_DUP_VAL_ON_INDEX = false;
+			$this->ignoreDupValOnIndex = false;
 		}
 
 		return $retVal;
@@ -509,6 +592,7 @@ class DatabaseOracle extends DatabaseBase {
 		if ( is_numeric( $col ) ) {
 			$bind = $val;
 			$val = null;
+
 			return $bind;
 		} elseif ( $includeCol ) {
 			$bind = "$col = ";
@@ -535,6 +619,13 @@ class DatabaseOracle extends DatabaseBase {
 		return $bind;
 	}
 
+	/**
+	 * @param string $table
+	 * @param array $row
+	 * @param string $fname
+	 * @return bool
+	 * @throws DBUnexpectedError
+	 */
 	private function insertOneRow( $table, $row, $fname ) {
 		global $wgContLang;
 
@@ -563,6 +654,7 @@ class DatabaseOracle extends DatabaseBase {
 		if ( ( $this->mLastResult = $stmt = oci_parse( $this->mConn, $sql ) ) === false ) {
 			$e = oci_error( $this->mConn );
 			$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 			return false;
 		}
 		foreach ( $row as $col => &$val ) {
@@ -585,9 +677,11 @@ class DatabaseOracle extends DatabaseBase {
 				if ( oci_bind_by_name( $stmt, ":$col", $val, -1, SQLT_CHR ) === false ) {
 					$e = oci_error( $stmt );
 					$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 					return false;
 				}
 			} else {
+				/** @var OCI_Lob[] $lob */
 				if ( ( $lob[$col] = oci_new_descriptor( $this->mConn, OCI_D_LOB ) ) === false ) {
 					$e = oci_error( $stmt );
 					throw new DBUnexpectedError( $this, "Cannot create LOB descriptor: " . $e['message'] );
@@ -599,10 +693,10 @@ class DatabaseOracle extends DatabaseBase {
 
 				if ( $col_type == 'BLOB' ) {
 					$lob[$col]->writeTemporary( $val, OCI_TEMP_BLOB );
-					oci_bind_by_name( $stmt, ":$col", $lob[$col], - 1, OCI_B_BLOB );
+					oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, OCI_B_BLOB );
 				} else {
 					$lob[$col]->writeTemporary( $val, OCI_TEMP_CLOB );
-					oci_bind_by_name( $stmt, ":$col", $lob[$col], - 1, OCI_B_CLOB );
+					oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, OCI_B_CLOB );
 				}
 			}
 		}
@@ -611,8 +705,9 @@ class DatabaseOracle extends DatabaseBase {
 
 		if ( oci_execute( $stmt, $this->execFlags() ) === false ) {
 			$e = oci_error( $stmt );
-			if ( !$this->ignore_DUP_VAL_ON_INDEX || $e['code'] != '1' ) {
+			if ( !$this->ignoreDupValOnIndex || $e['code'] != '1' ) {
 				$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 				return false;
 			} else {
 				$this->mAffectedRows = oci_num_rows( $stmt );
@@ -633,12 +728,12 @@ class DatabaseOracle extends DatabaseBase {
 			oci_commit( $this->mConn );
 		}
 
-		oci_free_statement( $stmt );
+		return oci_free_statement( $stmt );
 	}
 
 	function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = __METHOD__,
-		$insertOptions = array(), $selectOptions = array() )
-	{
+		$insertOptions = array(), $selectOptions = array()
+	) {
 		$destTable = $this->tableName( $destTable );
 		if ( !is_array( $selectOptions ) ) {
 			$selectOptions = array( $selectOptions );
@@ -651,8 +746,8 @@ class DatabaseOracle extends DatabaseBase {
 		}
 
 		if ( ( $sequenceData = $this->getSequenceData( $destTable ) ) !== false &&
-				!isset( $varMap[$sequenceData['column']] ) )
-		{
+			!isset( $varMap[$sequenceData['column']] )
+		) {
 			$varMap[$sequenceData['column']] = 'GET_SEQUENCE_VALUE(\'' . $sequenceData['sequence'] . '\')';
 		}
 
@@ -671,13 +766,13 @@ class DatabaseOracle extends DatabaseBase {
 		$sql .= " $tailOpts";
 
 		if ( in_array( 'IGNORE', $insertOptions ) ) {
-			$this->ignore_DUP_VAL_ON_INDEX = true;
+			$this->ignoreDupValOnIndex = true;
 		}
 
 		$retval = $this->query( $sql, $fname );
 
 		if ( in_array( 'IGNORE', $insertOptions ) ) {
-			$this->ignore_DUP_VAL_ON_INDEX = false;
+			$this->ignoreDupValOnIndex = false;
 		}
 
 		return $retval;
@@ -699,7 +794,9 @@ class DatabaseOracle extends DatabaseBase {
 			// add sequence column to each list of columns, when not set
 			foreach ( $rows as &$row ) {
 				if ( !isset( $row[$sequenceData['column']] ) ) {
-					$row[$sequenceData['column']] = $this->addIdentifierQuotes('GET_SEQUENCE_VALUE(\'' . $sequenceData['sequence'] . '\')');
+					$row[$sequenceData['column']] =
+						$this->addIdentifierQuotes( 'GET_SEQUENCE_VALUE(\'' .
+							$sequenceData['sequence'] . '\')' );
 				}
 			}
 		}
@@ -727,33 +824,45 @@ class DatabaseOracle extends DatabaseBase {
 
 	function tableNameInternal( $name ) {
 		$name = $this->tableName( $name );
+
 		return preg_replace( '/.*\.(.*)/', '$1', $name );
 	}
+
 	/**
 	 * Return the next in a sequence, save the value for retrieval via insertId()
-	 * @return null
+	 *
+	 * @param string $seqName
+	 * @return null|int
 	 */
 	function nextSequenceValue( $seqName ) {
 		$res = $this->query( "SELECT $seqName.nextval FROM dual" );
 		$row = $this->fetchRow( $res );
 		$this->mInsertId = $row[0];
+
 		return $this->mInsertId;
 	}
 
 	/**
 	 * Return sequence_name if table has a sequence
+	 *
+	 * @param string $table
 	 * @return bool
 	 */
 	private function getSequenceData( $table ) {
 		if ( $this->sequenceData == null ) {
 			$result = $this->doQuery( "SELECT lower(asq.sequence_name),
-				   lower(atc.table_name),
-				   lower(atc.column_name)
-			  FROM all_sequences asq, all_tab_columns atc
-			 WHERE decode(atc.table_name, '{$this->mTablePrefix}MWUSER', '{$this->mTablePrefix}USER', atc.table_name) || '_' ||
-				   atc.column_name || '_SEQ' = '{$this->mTablePrefix}' || asq.sequence_name
-			   AND asq.sequence_owner = upper('{$this->mDBname}')
-			   AND atc.owner = upper('{$this->mDBname}')" );
+				lower(atc.table_name),
+				lower(atc.column_name)
+			FROM all_sequences asq, all_tab_columns atc
+			WHERE decode(
+					atc.table_name,
+					'{$this->mTablePrefix}MWUSER',
+					'{$this->mTablePrefix}USER',
+					atc.table_name
+				) || '_' ||
+				atc.column_name || '_SEQ' = '{$this->mTablePrefix}' || asq.sequence_name
+				AND asq.sequence_owner = upper('{$this->mDBname}')
+				AND atc.owner = upper('{$this->mDBname}')" );
 
 			while ( ( $row = $result->fetchRow() ) !== false ) {
 				$this->sequenceData[$row[1]] = array(
@@ -763,12 +872,20 @@ class DatabaseOracle extends DatabaseBase {
 			}
 		}
 		$table = strtolower( $this->removeIdentifierQuotes( $this->tableName( $table ) ) );
+
 		return ( isset( $this->sequenceData[$table] ) ) ? $this->sequenceData[$table] : false;
 	}
 
-	# Returns the size of a text field, or -1 for "unlimited"
+	/**
+	 * Returns the size of a text field, or -1 for "unlimited"
+	 *
+	 * @param string $table
+	 * @param string $field
+	 * @return mixed
+	 */
 	function textFieldSize( $table, $field ) {
 		$fieldInfoData = $this->fieldInfo( $table, $field );
+
 		return $fieldInfoData->maxLength();
 	}
 
@@ -776,6 +893,7 @@ class DatabaseOracle extends DatabaseBase {
 		if ( $offset === false ) {
 			$offset = 0;
 		}
+
 		return "SELECT * FROM ($sql) WHERE rownum >= (1 + $offset) AND rownum < (1 + $limit + $offset)";
 	}
 
@@ -787,19 +905,24 @@ class DatabaseOracle extends DatabaseBase {
 		if ( $b instanceof Blob ) {
 			$b = $b->fetch();
 		}
+
 		return $b;
 	}
 
 	function unionQueries( $sqls, $all ) {
 		$glue = ' UNION ALL ';
-		return 'SELECT * ' . ( $all ? '' : '/* UNION_UNIQUE */ ' ) . 'FROM (' . implode( $glue, $sqls ) . ')';
+
+		return 'SELECT * ' . ( $all ? '' : '/* UNION_UNIQUE */ ' ) .
+			'FROM (' . implode( $glue, $sqls ) . ')';
 	}
 
 	function wasDeadlock() {
 		return $this->lastErrno() == 'OCI-00060';
 	}
 
-	function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
+	function duplicateTableStructure( $oldName, $newName, $temporary = false,
+		$fname = __METHOD__
+	) {
 		$temporary = $temporary ? 'TRUE' : 'FALSE';
 
 		$newName = strtoupper( $newName );
@@ -809,7 +932,8 @@ class DatabaseOracle extends DatabaseBase {
 		$oldPrefix = substr( $oldName, 0, strlen( $oldName ) - strlen( $tabName ) );
 		$newPrefix = strtoupper( $this->mTablePrefix );
 
-		return $this->doQuery( "BEGIN DUPLICATE_TABLE( '$tabName', '$oldPrefix', '$newPrefix', $temporary ); END;" );
+		return $this->doQuery( "BEGIN DUPLICATE_TABLE( '$tabName', " .
+			"'$oldPrefix', '$newPrefix', $temporary ); END;" );
 	}
 
 	function listTables( $prefix = null, $fname = __METHOD__ ) {
@@ -819,7 +943,8 @@ class DatabaseOracle extends DatabaseBase {
 		}
 
 		$owner = strtoupper( $this->mDBname );
-		$result = $this->doQuery( "SELECT table_name FROM all_tables WHERE owner='$owner' AND table_name NOT LIKE '%!_IDX\$_' ESCAPE '!' $listWhere" );
+		$result = $this->doQuery( "SELECT table_name FROM all_tables " .
+			"WHERE owner='$owner' AND table_name NOT LIKE '%!_IDX\$_' ESCAPE '!' $listWhere" );
 
 		// dirty code ... i know
 		$endArray = array();
@@ -851,6 +976,10 @@ class DatabaseOracle extends DatabaseBase {
 
 	/**
 	 * Return aggregated value function call
+	 *
+	 * @param array $valuedata
+	 * @param string $valuename
+	 * @return mixed
 	 */
 	public function aggregateValue( $valuedata, $valuename = 'value' ) {
 		return $valuedata;
@@ -871,7 +1000,7 @@ class DatabaseOracle extends DatabaseBase {
 	}
 
 	/**
-	 * @return string wikitext of a link to the server software's web site
+	 * @return string Wikitext of a link to the server software's web site
 	 */
 	public function getSoftwareLink() {
 		return '[{{int:version-db-oracle-url}} Oracle]';
@@ -882,15 +1011,22 @@ class DatabaseOracle extends DatabaseBase {
 	 */
 	function getServerVersion() {
 		//better version number, fallback on driver
-		$rset = $this->doQuery( 'SELECT version FROM product_component_version WHERE UPPER(product) LIKE \'ORACLE DATABASE%\'' );
+		$rset = $this->doQuery(
+			'SELECT version FROM product_component_version ' .
+				'WHERE UPPER(product) LIKE \'ORACLE DATABASE%\''
+		);
 		if ( !( $row = $rset->fetchRow() ) ) {
 			return oci_server_version( $this->mConn );
 		}
+
 		return $row['version'];
 	}
 
 	/**
 	 * Query whether a given index exists
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return bool
 	 */
 	function indexExists( $table, $index, $fname = __METHOD__ ) {
@@ -898,27 +1034,30 @@ class DatabaseOracle extends DatabaseBase {
 		$table = strtoupper( $this->removeIdentifierQuotes( $table ) );
 		$index = strtoupper( $index );
 		$owner = strtoupper( $this->mDBname );
-		$SQL = "SELECT 1 FROM all_indexes WHERE owner='$owner' AND index_name='{$table}_{$index}'";
-		$res = $this->doQuery( $SQL );
+		$sql = "SELECT 1 FROM all_indexes WHERE owner='$owner' AND index_name='{$table}_{$index}'";
+		$res = $this->doQuery( $sql );
 		if ( $res ) {
 			$count = $res->numRows();
 			$res->free();
 		} else {
 			$count = 0;
 		}
+
 		return $count != 0;
 	}
 
 	/**
 	 * Query whether a given table exists (in the given schema, or the default mw one if not given)
+	 * @param string $table
+	 * @param string $fname
 	 * @return bool
 	 */
 	function tableExists( $table, $fname = __METHOD__ ) {
 		$table = $this->tableName( $table );
 		$table = $this->addQuotes( strtoupper( $this->removeIdentifierQuotes( $table ) ) );
 		$owner = $this->addQuotes( strtoupper( $this->mDBname ) );
-		$SQL = "SELECT 1 FROM all_tables WHERE owner=$owner AND table_name=$table";
-		$res = $this->doQuery( $SQL );
+		$sql = "SELECT 1 FROM all_tables WHERE owner=$owner AND table_name=$table";
+		$res = $this->doQuery( $sql );
 		if ( $res && $res->numRows() > 0 ) {
 			$exists = true;
 		} else {
@@ -926,6 +1065,7 @@ class DatabaseOracle extends DatabaseBase {
 		}
 
 		$res->free();
+
 		return $exists;
 	}
 
@@ -935,8 +1075,8 @@ class DatabaseOracle extends DatabaseBase {
 	 * For internal calls. Use fieldInfo for normal usage.
 	 * Returns false if the field doesn't exist
 	 *
-	 * @param $table Array
-	 * @param $field String
+	 * @param array|string $table
+	 * @param string $field
 	 * @return ORAField|ORAResult
 	 */
 	private function fieldInfoMulti( $table, $field ) {
@@ -960,10 +1100,15 @@ class DatabaseOracle extends DatabaseBase {
 			$tableWhere = '= \'' . $table . '\'';
 		}
 
-		$fieldInfoStmt = oci_parse( $this->mConn, 'SELECT * FROM wiki_field_info_full WHERE table_name ' . $tableWhere . ' and column_name = \'' . $field . '\'' );
+		$fieldInfoStmt = oci_parse(
+			$this->mConn,
+			'SELECT * FROM wiki_field_info_full WHERE table_name ' .
+				$tableWhere . ' and column_name = \'' . $field . '\''
+		);
 		if ( oci_execute( $fieldInfoStmt, $this->execFlags() ) === false ) {
 			$e = oci_error( $fieldInfoStmt );
 			$this->reportQueryError( $e['message'], $e['code'], 'fieldInfo QUERY', __METHOD__ );
+
 			return false;
 		}
 		$res = new ORAResult( $this, $fieldInfoStmt );
@@ -982,19 +1127,21 @@ class DatabaseOracle extends DatabaseBase {
 			$this->mFieldInfoCache["$table.$field"] = $fieldInfoTemp;
 		}
 		$res->free();
+
 		return $fieldInfoTemp;
 	}
 
 	/**
 	 * @throws DBUnexpectedError
-	 * @param  $table
-	 * @param  $field
+	 * @param string $table
+	 * @param string $field
 	 * @return ORAField
 	 */
 	function fieldInfo( $table, $field ) {
 		if ( is_array( $table ) ) {
 			throw new DBUnexpectedError( $this, 'DatabaseOracle::fieldInfo called with table array!' );
 		}
+
 		return $this->fieldInfoMulti( $table, $field );
 	}
 
@@ -1022,7 +1169,16 @@ class DatabaseOracle extends DatabaseBase {
 		}
 	}
 
-	/* defines must comply with ^define\s*([^\s=]*)\s*=\s?'\{\$([^\}]*)\}'; */
+	/**
+	 * defines must comply with ^define\s*([^\s=]*)\s*=\s?'\{\$([^\}]*)\}';
+	 *
+	 * @param resource $fp
+	 * @param bool|string $lineCallback
+	 * @param bool|callable $resultCallback
+	 * @param string $fname
+	 * @param bool|callable $inputCallback
+	 * @return bool|string
+	 */
 	function sourceStream( $fp, $lineCallback = false, $resultCallback = false,
 		$fname = __METHOD__, $inputCallback = false ) {
 		$cmd = '';
@@ -1031,7 +1187,7 @@ class DatabaseOracle extends DatabaseBase {
 
 		$replacements = array();
 
-		while ( ! feof( $fp ) ) {
+		while ( !feof( $fp ) ) {
 			if ( $lineCallback ) {
 				call_user_func( $lineCallback );
 			}
@@ -1041,7 +1197,7 @@ class DatabaseOracle extends DatabaseBase {
 			if ( $sl < 0 ) {
 				continue;
 			}
-			if ( '-' == $line { 0 } && '-' == $line { 1 } ) {
+			if ( '-' == $line[0] && '-' == $line[1] ) {
 				continue;
 			}
 
@@ -1055,7 +1211,7 @@ class DatabaseOracle extends DatabaseBase {
 					$dollarquote = true;
 				}
 			} elseif ( !$dollarquote ) {
-				if ( ';' == $line { $sl } && ( $sl < 2 || ';' != $line { $sl - 1 } ) ) {
+				if ( ';' == $line[$sl] && ( $sl < 2 || ';' != $line[$sl - 1] ) ) {
 					$done = true;
 					$line = substr( $line, 0, $sl );
 				}
@@ -1088,6 +1244,7 @@ class DatabaseOracle extends DatabaseBase {
 
 					if ( false === $res ) {
 						$err = $this->lastError();
+
 						return "Query \"{$cmd}\" failed with error code \"$err\".\n";
 					}
 				}
@@ -1096,6 +1253,7 @@ class DatabaseOracle extends DatabaseBase {
 				$done = false;
 			}
 		}
+
 		return true;
 	}
 
@@ -1114,8 +1272,10 @@ class DatabaseOracle extends DatabaseBase {
 			if ( $e['code'] != '1435' ) {
 				$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
 			}
+
 			return false;
 		}
+
 		return true;
 	}
 
@@ -1128,6 +1288,7 @@ class DatabaseOracle extends DatabaseBase {
 		if ( isset( $wgContLang->mLoaded ) && $wgContLang->mLoaded ) {
 			$s = $wgContLang->checkTitleEncoding( $s );
 		}
+
 		return "'" . $this->strencode( $s ) . "'";
 	}
 
@@ -1135,6 +1296,7 @@ class DatabaseOracle extends DatabaseBase {
 		if ( !$this->getFlag( DBO_DDLMODE ) ) {
 			$s = '/*Q*/' . $s;
 		}
+
 		return $s;
 	}
 
@@ -1173,13 +1335,17 @@ class DatabaseOracle extends DatabaseBase {
 				$conds2[$col] = $val;
 			}
 		}
+
 		return $conds2;
 	}
 
-	function selectRow( $table, $vars, $conds, $fname = __METHOD__, $options = array(), $join_conds = array() ) {
+	function selectRow( $table, $vars, $conds, $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	) {
 		if ( is_array( $conds ) ) {
 			$conds = $this->wrapConditionsForWhere( $table, $conds );
 		}
+
 		return parent::selectRow( $table, $vars, $conds, $fname, $options, $join_conds );
 	}
 
@@ -1187,10 +1353,8 @@ class DatabaseOracle extends DatabaseBase {
 	 * Returns an optional USE INDEX clause to go after the table, and a
 	 * string to go at the end of the query
 	 *
-	 * @private
-	 *
-	 * @param array $options an associative array of options to be turned into
-	 *              an SQL query, valid keys are listed in the function.
+	 * @param array $options An associative array of options to be turned into
+	 *   an SQL query, valid keys are listed in the function.
 	 * @return array
 	 */
 	function makeSelectOptions( $options ) {
@@ -1216,7 +1380,7 @@ class DatabaseOracle extends DatabaseBase {
 			$startOpts .= 'DISTINCT';
 		}
 
-		if ( isset( $options['USE INDEX'] ) && ! is_array( $options['USE INDEX'] ) ) {
+		if ( isset( $options['USE INDEX'] ) && !is_array( $options['USE INDEX'] ) ) {
 			$useIndex = $this->useIndexClause( $options['USE INDEX'] );
 		} else {
 			$useIndex = '';
@@ -1233,21 +1397,41 @@ class DatabaseOracle extends DatabaseBase {
 		// all deletions on these tables have transactions so final failure rollbacks these updates
 		$table = $this->tableName( $table );
 		if ( $table == $this->tableName( 'user' ) ) {
-				$this->update( 'archive', array( 'ar_user' => 0 ), array( 'ar_user' => $conds['user_id'] ), $fname );
-				$this->update( 'ipblocks', array( 'ipb_user' => 0 ), array( 'ipb_user' => $conds['user_id'] ), $fname );
-				$this->update( 'image', array( 'img_user' => 0 ), array( 'img_user' => $conds['user_id'] ), $fname );
-				$this->update( 'oldimage', array( 'oi_user' => 0 ), array( 'oi_user' => $conds['user_id'] ), $fname );
-				$this->update( 'filearchive', array( 'fa_deleted_user' => 0 ), array( 'fa_deleted_user' => $conds['user_id'] ), $fname );
-				$this->update( 'filearchive', array( 'fa_user' => 0 ), array( 'fa_user' => $conds['user_id'] ), $fname );
-				$this->update( 'uploadstash', array( 'us_user' => 0 ), array( 'us_user' => $conds['user_id'] ), $fname );
-				$this->update( 'recentchanges', array( 'rc_user' => 0 ), array( 'rc_user' => $conds['user_id'] ), $fname );
-				$this->update( 'logging', array( 'log_user' => 0 ), array( 'log_user' => $conds['user_id'] ), $fname );
+			$this->update( 'archive', array( 'ar_user' => 0 ),
+				array( 'ar_user' => $conds['user_id'] ), $fname );
+			$this->update( 'ipblocks', array( 'ipb_user' => 0 ),
+				array( 'ipb_user' => $conds['user_id'] ), $fname );
+			$this->update( 'image', array( 'img_user' => 0 ),
+				array( 'img_user' => $conds['user_id'] ), $fname );
+			$this->update( 'oldimage', array( 'oi_user' => 0 ),
+				array( 'oi_user' => $conds['user_id'] ), $fname );
+			$this->update( 'filearchive', array( 'fa_deleted_user' => 0 ),
+				array( 'fa_deleted_user' => $conds['user_id'] ), $fname );
+			$this->update( 'filearchive', array( 'fa_user' => 0 ),
+				array( 'fa_user' => $conds['user_id'] ), $fname );
+			$this->update( 'uploadstash', array( 'us_user' => 0 ),
+				array( 'us_user' => $conds['user_id'] ), $fname );
+			$this->update( 'recentchanges', array( 'rc_user' => 0 ),
+				array( 'rc_user' => $conds['user_id'] ), $fname );
+			$this->update( 'logging', array( 'log_user' => 0 ),
+				array( 'log_user' => $conds['user_id'] ), $fname );
 		} elseif ( $table == $this->tableName( 'image' ) ) {
-				$this->update( 'oldimage', array( 'oi_name' => 0 ), array( 'oi_name' => $conds['img_name'] ), $fname );
+			$this->update( 'oldimage', array( 'oi_name' => 0 ),
+				array( 'oi_name' => $conds['img_name'] ), $fname );
 		}
+
 		return parent::delete( $table, $conds, $fname );
 	}
 
+	/**
+	 * @param string $table
+	 * @param array $values
+	 * @param array $conds
+	 * @param string $fname
+	 * @param array $options
+	 * @return bool
+	 * @throws DBUnexpectedError
+	 */
 	function update( $table, $values, $conds, $fname = __METHOD__, $options = array() ) {
 		global $wgContLang;
 
@@ -1275,6 +1459,7 @@ class DatabaseOracle extends DatabaseBase {
 		if ( ( $this->mLastResult = $stmt = oci_parse( $this->mConn, $sql ) ) === false ) {
 			$e = oci_error( $this->mConn );
 			$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 			return false;
 		}
 		foreach ( $values as $col => &$val ) {
@@ -1296,9 +1481,11 @@ class DatabaseOracle extends DatabaseBase {
 				if ( oci_bind_by_name( $stmt, ":$col", $val ) === false ) {
 					$e = oci_error( $stmt );
 					$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 					return false;
 				}
 			} else {
+				/** @var OCI_Lob[] $lob */
 				if ( ( $lob[$col] = oci_new_descriptor( $this->mConn, OCI_D_LOB ) ) === false ) {
 					$e = oci_error( $stmt );
 					throw new DBUnexpectedError( $this, "Cannot create LOB descriptor: " . $e['message'] );
@@ -1310,10 +1497,10 @@ class DatabaseOracle extends DatabaseBase {
 
 				if ( $col_type == 'BLOB' ) {
 					$lob[$col]->writeTemporary( $val );
-					oci_bind_by_name( $stmt, ":$col", $lob[$col], - 1, SQLT_BLOB );
+					oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, SQLT_BLOB );
 				} else {
 					$lob[$col]->writeTemporary( $val );
-					oci_bind_by_name( $stmt, ":$col", $lob[$col], - 1, OCI_B_CLOB );
+					oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, OCI_B_CLOB );
 				}
 			}
 		}
@@ -1322,8 +1509,9 @@ class DatabaseOracle extends DatabaseBase {
 
 		if ( oci_execute( $stmt, $this->execFlags() ) === false ) {
 			$e = oci_error( $stmt );
-			if ( !$this->ignore_DUP_VAL_ON_INDEX || $e['code'] != '1' ) {
+			if ( !$this->ignoreDupValOnIndex || $e['code'] != '1' ) {
 				$this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
+
 				return false;
 			} else {
 				$this->mAffectedRows = oci_num_rows( $stmt );
@@ -1344,7 +1532,7 @@ class DatabaseOracle extends DatabaseBase {
 			oci_commit( $this->mConn );
 		}
 
-		oci_free_statement( $stmt );
+		return oci_free_statement( $stmt );
 	}
 
 	function bitNot( $field ) {
@@ -1360,9 +1548,6 @@ class DatabaseOracle extends DatabaseBase {
 		return 'BITOR(' . $fieldLeft . ', ' . $fieldRight . ')';
 	}
 
-	function setFakeMaster( $enabled = true ) {
-	}
-
 	function getDBname() {
 		return $this->mDBname;
 	}
@@ -1371,6 +1556,14 @@ class DatabaseOracle extends DatabaseBase {
 		return $this->mServer;
 	}
 
+	public function buildGroupConcatField(
+		$delim, $table, $field, $conds = '', $join_conds = array()
+	) {
+		$fld = "LISTAGG($field," . $this->addQuotes( $delim ) . ") WITHIN GROUP (ORDER BY $field)";
+
+		return '(' . $this->selectSQLText( $table, $fld, $conds, null, array(), $join_conds ) . ')';
+	}
+
 	public function getSearchEngine() {
 		return 'SearchOracle';
 	}
@@ -1378,5 +1571,4 @@ class DatabaseOracle extends DatabaseBase {
 	public function getInfinity() {
 		return '31-12-2030 12:00:00.000000';
 	}
-
-} // end DatabaseOracle class
+}
diff --git a/includes/db/DatabasePostgres.php b/includes/db/DatabasePostgres.php
index 0bd966ba..ce14d7a9 100644
--- a/includes/db/DatabasePostgres.php
+++ b/includes/db/DatabasePostgres.php
@@ -26,9 +26,9 @@ class PostgresField implements Field {
 		$has_default, $default;
 
 	/**
-	 * @param $db DatabaseBase
-	 * @param  $table
-	 * @param  $field
+	 * @param DatabaseBase $db
+	 * @param string $table
+	 * @param string $field
 	 * @return null|PostgresField
 	 */
 	static function fromText( $db, $table, $field ) {
@@ -79,6 +79,7 @@ SQL;
 		$n->conname = $row->conname;
 		$n->has_default = ( $row->atthasdef === 't' );
 		$n->default = $row->adsrc;
+
 		return $n;
 	}
 
@@ -113,8 +114,10 @@ SQL;
 	function conname() {
 		return $this->conname;
 	}
+
 	/**
 	 * @since 1.19
+	 * @return bool|mixed
 	 */
 	function defaultValue() {
 		if ( $this->has_default ) {
@@ -123,7 +126,6 @@ SQL;
 			return false;
 		}
 	}
-
 }
 
 /**
@@ -134,8 +136,7 @@ SQL;
  * @ingroup Database
  */
 class PostgresTransactionState {
-
-	static $WATCHED = array(
+	private static $WATCHED = array(
 		array(
 			"desc" => "%s: Connection state changed from %s -> %s\n",
 			"states" => array(
@@ -155,6 +156,12 @@ class PostgresTransactionState {
 		)
 	);
 
+	/** @var array */
+	private $mNewState;
+
+	/** @var array */
+	private $mCurrentState;
+
 	public function __construct( $conn ) {
 		$this->mConn = $conn;
 		$this->update();
@@ -181,7 +188,6 @@ class PostgresTransactionState {
 					}
 					$old = next( $this->mCurrentState );
 					$new = next( $this->mNewState );
-
 				}
 			}
 		}
@@ -211,21 +217,23 @@ class PostgresTransactionState {
  * @since 1.19
  */
 class SavepointPostgres {
-	/**
-	 * Establish a savepoint within a transaction
-	 */
+	/** @var DatabaseBase Establish a savepoint within a transaction */
 	protected $dbw;
 	protected $id;
 	protected $didbegin;
 
+	/**
+	 * @param DatabaseBase $dbw
+	 * @param int $id
+	 */
 	public function __construct( $dbw, $id ) {
 		$this->dbw = $dbw;
 		$this->id = $id;
 		$this->didbegin = false;
 		/* If we are not in a transaction, we need to be for savepoint trickery */
 		if ( !$dbw->trxLevel() ) {
-				$dbw->begin( "FOR SAVEPOINT" );
-				$this->didbegin = true;
+			$dbw->begin( "FOR SAVEPOINT" );
+			$this->didbegin = true;
 		}
 	}
 
@@ -247,10 +255,10 @@ class SavepointPostgres {
 		global $wgDebugDBTransactions;
 		if ( $this->dbw->doQuery( $keyword . " " . $this->id ) !== false ) {
 			if ( $wgDebugDBTransactions ) {
-				wfDebug( sprintf ( $msg_ok, $this->id ) );
+				wfDebug( sprintf( $msg_ok, $this->id ) );
 			}
 		} else {
-			wfDebug( sprintf ( $msg_failed, $this->id ) );
+			wfDebug( sprintf( $msg_failed, $this->id ) );
 		}
 	}
 
@@ -284,10 +292,26 @@ class SavepointPostgres {
  * @ingroup Database
  */
 class DatabasePostgres extends DatabaseBase {
-	var $mInsertId = null;
-	var $mLastResult = null;
-	var $numeric_version = null;
-	var $mAffectedRows = null;
+	/** @var resource */
+	protected $mLastResult = null;
+
+	/** @var int The number of rows affected as an integer */
+	protected $mAffectedRows = null;
+
+	/** @var int */
+	private $mInsertId = null;
+
+	/** @var float|string */
+	private $numericVersion = null;
+
+	/** @var string Connect string to open a PostgreSQL connection */
+	private $connectString;
+
+	/** @var PostgresTransactionState */
+	private $mTransactionState;
+
+	/** @var string */
+	private $mCoreSchema;
 
 	function getType() {
 		return 'postgres';
@@ -296,32 +320,42 @@ class DatabasePostgres extends DatabaseBase {
 	function cascadingDeletes() {
 		return true;
 	}
+
 	function cleanupTriggers() {
 		return true;
 	}
+
 	function strictIPs() {
 		return true;
 	}
+
 	function realTimestamps() {
 		return true;
 	}
+
 	function implicitGroupby() {
 		return false;
 	}
+
 	function implicitOrderby() {
 		return false;
 	}
+
 	function searchableIPs() {
 		return true;
 	}
+
 	function functionalIndexes() {
 		return true;
 	}
 
 	function hasConstraint( $name ) {
-		$SQL = "SELECT 1 FROM pg_catalog.pg_constraint c, pg_catalog.pg_namespace n WHERE c.connamespace = n.oid AND conname = '" .
-				pg_escape_string( $this->mConn, $name ) . "' AND n.nspname = '" . pg_escape_string( $this->mConn, $this->getCoreSchema() ) . "'";
-		$res = $this->doQuery( $SQL );
+		$sql = "SELECT 1 FROM pg_catalog.pg_constraint c, pg_catalog.pg_namespace n " .
+			"WHERE c.connamespace = n.oid AND conname = '" .
+			pg_escape_string( $this->mConn, $name ) . "' AND n.nspname = '" .
+			pg_escape_string( $this->mConn, $this->getCoreSchema() ) . "'";
+		$res = $this->doQuery( $sql );
+
 		return $this->numRows( $res );
 	}
 
@@ -331,19 +365,24 @@ class DatabasePostgres extends DatabaseBase {
 	 * @param string $user
 	 * @param string $password
 	 * @param string $dbName
-	 * @throws DBConnectionError
+	 * @throws DBConnectionError|Exception
 	 * @return DatabaseBase|null
 	 */
 	function open( $server, $user, $password, $dbName ) {
 		# Test for Postgres support, to avoid suppressed fatal error
 		if ( !function_exists( 'pg_connect' ) ) {
-			throw new DBConnectionError( $this, "Postgres functions missing, have you compiled PHP with the --with-pgsql option?\n (Note: if you recently installed PHP, you may need to restart your webserver and database)\n" );
+			throw new DBConnectionError(
+				$this,
+				"Postgres functions missing, have you compiled PHP with the --with-pgsql\n" .
+				"option? (Note: if you recently installed PHP, you may need to restart your\n" .
+				"webserver and database)\n"
+			);
 		}
 
 		global $wgDBport;
 
 		if ( !strlen( $user ) ) { # e.g. the class is being loaded
-			return;
+			return null;
 		}
 
 		$this->mServer = $server;
@@ -370,12 +409,20 @@ class DatabasePostgres extends DatabaseBase {
 		$this->connectString = $this->makeConnectionString( $connectVars, PGSQL_CONNECT_FORCE_NEW );
 		$this->close();
 		$this->installErrorHandler();
-		$this->mConn = pg_connect( $this->connectString );
+
+		try {
+			$this->mConn = pg_connect( $this->connectString );
+		} catch ( Exception $ex ) {
+			$this->restoreErrorHandler();
+			throw $ex;
+		}
+
 		$phpError = $this->restoreErrorHandler();
 
 		if ( !$this->mConn ) {
 			wfDebug( "DB connection error\n" );
-			wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
+			wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " .
+				substr( $password, 0, 3 ) . "...\n" );
 			wfDebug( $this->lastError() . "\n" );
 			throw new DBConnectionError( $this, str_replace( "\n", ' ', $phpError ) );
 		}
@@ -406,7 +453,8 @@ class DatabasePostgres extends DatabaseBase {
 	/**
 	 * Postgres doesn't support selectDB in the same way MySQL does. So if the
 	 * DB name doesn't match the open connection, open a new one
-	 * @return
+	 * @param string $db
+	 * @return bool
 	 */
 	function selectDB( $db ) {
 		if ( $this->mDBname !== $db ) {
@@ -421,6 +469,7 @@ class DatabasePostgres extends DatabaseBase {
 		foreach ( $vars as $name => $value ) {
 			$s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
 		}
+
 		return $s;
 	}
 
@@ -447,38 +496,44 @@ class DatabasePostgres extends DatabaseBase {
 		if ( pg_result_error( $this->mLastResult ) ) {
 			return false;
 		}
+
 		return $this->mLastResult;
 	}
 
 	protected function dumpError() {
-		$diags = array( PGSQL_DIAG_SEVERITY,
-				PGSQL_DIAG_SQLSTATE,
-				PGSQL_DIAG_MESSAGE_PRIMARY,
-				PGSQL_DIAG_MESSAGE_DETAIL,
-				PGSQL_DIAG_MESSAGE_HINT,
-				PGSQL_DIAG_STATEMENT_POSITION,
-				PGSQL_DIAG_INTERNAL_POSITION,
-				PGSQL_DIAG_INTERNAL_QUERY,
-				PGSQL_DIAG_CONTEXT,
-				PGSQL_DIAG_SOURCE_FILE,
-				PGSQL_DIAG_SOURCE_LINE,
-				PGSQL_DIAG_SOURCE_FUNCTION );
+		$diags = array(
+			PGSQL_DIAG_SEVERITY,
+			PGSQL_DIAG_SQLSTATE,
+			PGSQL_DIAG_MESSAGE_PRIMARY,
+			PGSQL_DIAG_MESSAGE_DETAIL,
+			PGSQL_DIAG_MESSAGE_HINT,
+			PGSQL_DIAG_STATEMENT_POSITION,
+			PGSQL_DIAG_INTERNAL_POSITION,
+			PGSQL_DIAG_INTERNAL_QUERY,
+			PGSQL_DIAG_CONTEXT,
+			PGSQL_DIAG_SOURCE_FILE,
+			PGSQL_DIAG_SOURCE_LINE,
+			PGSQL_DIAG_SOURCE_FUNCTION
+		);
 		foreach ( $diags as $d ) {
-			wfDebug( sprintf( "PgSQL ERROR(%d): %s\n", $d, pg_result_error_field( $this->mLastResult, $d ) ) );
+			wfDebug( sprintf( "PgSQL ERROR(%d): %s\n",
+				$d, pg_result_error_field( $this->mLastResult, $d ) ) );
 		}
 	}
 
 	function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
-		/* Transaction stays in the ERROR state until rolledback */
 		if ( $tempIgnore ) {
 			/* Check for constraint violation */
 			if ( $errno === '23505' ) {
 				parent::reportQueryError( $error, $errno, $sql, $fname, $tempIgnore );
+
 				return;
 			}
 		}
-		/* Don't ignore serious errors */
-		$this->rollback( __METHOD__ );
+		/* Transaction stays in the ERROR state until rolledback */
+		if ( $this->mTrxLevel ) {
+			$this->rollback( __METHOD__ );
+		};
 		parent::reportQueryError( $error, $errno, $sql, $fname, false );
 	}
 
@@ -486,6 +541,10 @@ class DatabasePostgres extends DatabaseBase {
 		return $this->query( $sql, $fname, true );
 	}
 
+	/**
+	 * @param stdClass|ResultWrapper $res
+	 * @throws DBUnexpectedError
+	 */
 	function freeResult( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
@@ -498,6 +557,11 @@ class DatabasePostgres extends DatabaseBase {
 		}
 	}
 
+	/**
+	 * @param ResultWrapper|stdClass $res
+	 * @return stdClass
+	 * @throws DBUnexpectedError
+	 */
 	function fetchObject( $res ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
@@ -510,8 +574,12 @@ class DatabasePostgres extends DatabaseBase {
 		# @todo hashar: not sure if the following test really trigger if the object
 		#          fetching failed.
 		if ( pg_last_error( $this->mConn ) ) {
-			throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
+			throw new DBUnexpectedError(
+				$this,
+				'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) )
+			);
 		}
+
 		return $row;
 	}
 
@@ -523,8 +591,12 @@ class DatabasePostgres extends DatabaseBase {
 		$row = pg_fetch_array( $res );
 		wfRestoreWarnings();
 		if ( pg_last_error( $this->mConn ) ) {
-			throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
+			throw new DBUnexpectedError(
+				$this,
+				'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) )
+			);
 		}
+
 		return $row;
 	}
 
@@ -536,8 +608,12 @@ class DatabasePostgres extends DatabaseBase {
 		$n = pg_num_rows( $res );
 		wfRestoreWarnings();
 		if ( pg_last_error( $this->mConn ) ) {
-			throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
+			throw new DBUnexpectedError(
+				$this,
+				'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) )
+			);
 		}
+
 		return $n;
 	}
 
@@ -545,6 +621,7 @@ class DatabasePostgres extends DatabaseBase {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
+
 		return pg_num_fields( $res );
 	}
 
@@ -552,6 +629,7 @@ class DatabasePostgres extends DatabaseBase {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
+
 		return pg_field_name( $res, $n );
 	}
 
@@ -559,16 +637,22 @@ class DatabasePostgres extends DatabaseBase {
 	 * Return the result of the last call to nextSequenceValue();
 	 * This must be called after nextSequenceValue().
 	 *
-	 * @return integer|null
+	 * @return int|null
 	 */
 	function insertId() {
 		return $this->mInsertId;
 	}
 
+	/**
+	 * @param mixed $res
+	 * @param int $row
+	 * @return bool
+	 */
 	function dataSeek( $res, $row ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
+
 		return pg_result_seek( $res, $row );
 	}
 
@@ -583,6 +667,7 @@ class DatabasePostgres extends DatabaseBase {
 			return 'No database connection';
 		}
 	}
+
 	function lastErrno() {
 		if ( $this->mLastResult ) {
 			return pg_result_error_field( $this->mLastResult, PGSQL_DIAG_SQLSTATE );
@@ -599,6 +684,7 @@ class DatabasePostgres extends DatabaseBase {
 		if ( empty( $this->mLastResult ) ) {
 			return 0;
 		}
+
 		return pg_affected_rows( $this->mLastResult );
 	}
 
@@ -608,9 +694,17 @@ class DatabasePostgres extends DatabaseBase {
 	 * This is not necessarily an accurate estimate, so use sparingly
 	 * Returns -1 if count cannot be found
 	 * Takes same arguments as Database::select()
+	 *
+	 * @param string $table
+	 * @param string $vars
+	 * @param string $conds
+	 * @param string $fname
+	 * @param array $options
 	 * @return int
 	 */
-	function estimateRowCount( $table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array() ) {
+	function estimateRowCount( $table, $vars = '*', $conds = '',
+		$fname = __METHOD__, $options = array()
+	) {
 		$options['EXPLAIN'] = true;
 		$res = $this->select( $table, $vars, $conds, $fname, $options );
 		$rows = -1;
@@ -621,12 +715,17 @@ class DatabasePostgres extends DatabaseBase {
 				$rows = $count[1];
 			}
 		}
+
 		return $rows;
 	}
 
 	/**
 	 * Returns information about an index
 	 * If errors are explicitly ignored, returns NULL on failure
+	 *
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return bool|null
 	 */
 	function indexInfo( $table, $index, $fname = __METHOD__ ) {
@@ -640,6 +739,7 @@ class DatabasePostgres extends DatabaseBase {
 				return $row;
 			}
 		}
+
 		return false;
 	}
 
@@ -647,7 +747,9 @@ class DatabasePostgres extends DatabaseBase {
 	 * Returns is of attributes used in index
 	 *
 	 * @since 1.19
-	 * @return Array
+	 * @param string $index
+	 * @param bool|string $schema
+	 * @return array
 	 */
 	function indexAttributes( $index, $schema = false ) {
 		if ( $schema === false ) {
@@ -702,6 +804,7 @@ __INDEXATTR__;
 		} else {
 			return null;
 		}
+
 		return $a;
 	}
 
@@ -714,10 +817,8 @@ __INDEXATTR__;
 		if ( !$res ) {
 			return null;
 		}
-		foreach ( $res as $row ) {
-			return true;
-		}
-		return false;
+
+		return $res->numRows() > 0;
 	}
 
 	/**
@@ -727,10 +828,15 @@ __INDEXATTR__;
 	 * In Postgres when using FOR UPDATE, only the main table and tables that are inner joined
 	 * can be locked. That means tables in an outer join cannot be FOR UPDATE locked. Trying to do
 	 * so causes a DB error. This wrapper checks which tables can be locked and adjusts it accordingly.
+	 *
+	 * MySQL uses "ORDER BY NULL" as an optimization hint, but that syntax is illegal in PostgreSQL.
+	 * @see DatabaseBase::selectSQLText
 	 */
-	function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__, $options = array(), $join_conds = array() ) {
+	function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	) {
 		if ( is_array( $options ) ) {
-			$forUpdateKey = array_search( 'FOR UPDATE', $options );
+			$forUpdateKey = array_search( 'FOR UPDATE', $options, true );
 			if ( $forUpdateKey !== false && $join_conds ) {
 				unset( $options[$forUpdateKey] );
 
@@ -740,6 +846,10 @@ __INDEXATTR__;
 					}
 				}
 			}
+
+			if ( isset( $options['ORDER BY'] ) && $options['ORDER BY'] == 'NULL' ) {
+				unset( $options['ORDER BY'] );
+			}
 		}
 
 		return parent::selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
@@ -751,11 +861,10 @@ __INDEXATTR__;
 	 * $args may be a single associative array, or an array of these with numeric keys,
 	 * for multi-row insert (Postgres version 8.2 and above only).
 	 *
-	 * @param $table   String: Name of the table to insert to.
-	 * @param $args    Array: Items to insert into the table.
-	 * @param $fname   String: Name of the function, for profiling
-	 * @param string $options or Array. Valid options: IGNORE
-	 *
+	 * @param string $table Name of the table to insert to.
+	 * @param array $args Items to insert into the table.
+	 * @param string $fname Name of the function, for profiling
+	 * @param array|string $options String or array. Valid options: IGNORE
 	 * @return bool Success of insert operation. IGNORE always returns true.
 	 */
 	function insert( $table, $args, $fname = __METHOD__, $options = array() ) {
@@ -764,7 +873,7 @@ __INDEXATTR__;
 		}
 
 		$table = $this->tableName( $table );
-		if ( !isset( $this->numeric_version ) ) {
+		if ( !isset( $this->numericVersion ) ) {
 			$this->getServerVersion();
 		}
 
@@ -793,7 +902,7 @@ __INDEXATTR__;
 		$sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 
 		if ( $multi ) {
-			if ( $this->numeric_version >= 8.2 && !$savepoint ) {
+			if ( $this->numericVersion >= 8.2 && !$savepoint ) {
 				$first = true;
 				foreach ( $args as $row ) {
 					if ( $first ) {
@@ -853,7 +962,7 @@ __INDEXATTR__;
 			}
 		}
 		if ( $savepoint ) {
-			$olde = error_reporting( $olde );
+			error_reporting( $olde );
 			$savepoint->commit();
 
 			// Set the affected row count for the whole operation
@@ -869,15 +978,23 @@ __INDEXATTR__;
 	/**
 	 * INSERT SELECT wrapper
 	 * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
-	 * Source items may be literals rather then field names, but strings should be quoted with Database::addQuotes()
+	 * Source items may be literals rather then field names, but strings should
+	 * be quoted with Database::addQuotes()
 	 * $conds may be "*" to copy the whole table
 	 * srcTable may be an array of tables.
 	 * @todo FIXME: Implement this a little better (seperate select/insert)?
+	 *
+	 * @param string $destTable
+	 * @param array|string $srcTable
+	 * @param array $varMap
+	 * @param array $conds
+	 * @param string $fname
+	 * @param array $insertOptions
+	 * @param array $selectOptions
 	 * @return bool
 	 */
 	function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = __METHOD__,
-		$insertOptions = array(), $selectOptions = array() )
-	{
+		$insertOptions = array(), $selectOptions = array() ) {
 		$destTable = $this->tableName( $destTable );
 
 		if ( !is_array( $insertOptions ) ) {
@@ -907,8 +1024,8 @@ __INDEXATTR__;
 		}
 
 		$sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
-				" SELECT $startOpts " . implode( ',', $varMap ) .
-				" FROM $srcTable $useIndex";
+			" SELECT $startOpts " . implode( ',', $varMap ) .
+			" FROM $srcTable $useIndex";
 
 		if ( $conds != '*' ) {
 			$sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
@@ -925,7 +1042,7 @@ __INDEXATTR__;
 				$savepoint->release();
 				$numrowsinserted++;
 			}
-			$olde = error_reporting( $olde );
+			error_reporting( $olde );
 			$savepoint->commit();
 
 			// Set the affected row count for the whole operation
@@ -957,25 +1074,31 @@ __INDEXATTR__;
 
 	/**
 	 * Return the next in a sequence, save the value for retrieval via insertId()
-	 * @return null
+	 *
+	 * @param string $seqName
+	 * @return int|null
 	 */
 	function nextSequenceValue( $seqName ) {
 		$safeseq = str_replace( "'", "''", $seqName );
 		$res = $this->query( "SELECT nextval('$safeseq')" );
 		$row = $this->fetchRow( $res );
 		$this->mInsertId = $row[0];
+
 		return $this->mInsertId;
 	}
 
 	/**
 	 * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
-	 * @return
+	 *
+	 * @param string $seqName
+	 * @return int
 	 */
 	function currentSequenceValue( $seqName ) {
 		$safeseq = str_replace( "'", "''", $seqName );
 		$res = $this->query( "SELECT currval('$safeseq')" );
 		$row = $this->fetchRow( $res );
 		$currval = $row[0];
+
 		return $currval;
 	}
 
@@ -993,6 +1116,7 @@ __INDEXATTR__;
 		} else {
 			$size = $row->size;
 		}
+
 		return $size;
 	}
 
@@ -1007,7 +1131,9 @@ __INDEXATTR__;
 	function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
 		$newName = $this->addIdentifierQuotes( $newName );
 		$oldName = $this->addIdentifierQuotes( $oldName );
-		return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName (LIKE $oldName INCLUDING DEFAULTS)", $fname );
+
+		return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName " .
+			"(LIKE $oldName INCLUDING DEFAULTS)", $fname );
 	}
 
 	function listTables( $prefix = null, $fname = __METHOD__ ) {
@@ -1030,7 +1156,7 @@ __INDEXATTR__;
 		return wfTimestamp( TS_POSTGRES, $ts );
 	}
 
-	/*
+	/**
 	 * Posted by cc[plus]php[at]c2se[dot]com on 25-Mar-2009 09:12
 	 * to http://www.php.net/manual/en/ref.pgsql.php
 	 *
@@ -1042,10 +1168,10 @@ __INDEXATTR__;
 	 * This should really be handled by PHP PostgreSQL module
 	 *
 	 * @since 1.19
-	 * @param $text   string: postgreql array returned in a text form like {a,b}
-	 * @param $output string
-	 * @param $limit  int
-	 * @param $offset int
+	 * @param string $text Postgreql array returned in a text form like {a,b}
+	 * @param string $output
+	 * @param int $limit
+	 * @param int $offset
 	 * @return string
 	 */
 	function pg_array_parse( $text, &$output, $limit = false, $offset = 1 ) {
@@ -1062,8 +1188,8 @@ __INDEXATTR__;
 					$text, $match, 0, $offset );
 				$offset += strlen( $match[0] );
 				$output[] = ( '"' != $match[1][0]
-						? $match[1]
-						: stripcslashes( substr( $match[1], 1, -1 ) ) );
+					? $match[1]
+					: stripcslashes( substr( $match[1], 1, -1 ) ) );
 				if ( '},' == $match[3] ) {
 					return $output;
 				}
@@ -1071,18 +1197,22 @@ __INDEXATTR__;
 				$offset = $this->pg_array_parse( $text, $output, $limit, $offset + 1 );
 			}
 		} while ( $limit > $offset );
+
 		return $output;
 	}
 
 	/**
 	 * Return aggregated value function call
+	 * @param array $valuedata
+	 * @param string $valuename
+	 * @return array
 	 */
 	public function aggregateValue( $valuedata, $valuename = 'value' ) {
 		return $valuedata;
 	}
 
 	/**
-	 * @return string wikitext of a link to the server software's web site
+	 * @return string Wikitext of a link to the server software's web site
 	 */
 	public function getSoftwareLink() {
 		return '[{{int:version-db-postgres-url}} PostgreSQL]';
@@ -1093,11 +1223,12 @@ __INDEXATTR__;
 	 * Needs transaction
 	 *
 	 * @since 1.19
-	 * @return string return default schema for the current session
+	 * @return string Default schema for the current session
 	 */
 	function getCurrentSchema() {
 		$res = $this->query( "SELECT current_schema()", __METHOD__ );
 		$row = $this->fetchRow( $res );
+
 		return $row[0];
 	}
 
@@ -1109,13 +1240,15 @@ __INDEXATTR__;
 	 * @see getSearchPath()
 	 * @see setSearchPath()
 	 * @since 1.19
-	 * @return array list of actual schemas for the current sesson
+	 * @return array List of actual schemas for the current sesson
 	 */
 	function getSchemas() {
 		$res = $this->query( "SELECT current_schemas(false)", __METHOD__ );
 		$row = $this->fetchRow( $res );
 		$schemas = array();
+
 		/* PHP pgsql support does not support array type, "{a,b}" string is returned */
+
 		return $this->pg_array_parse( $row[0], $schemas );
 	}
 
@@ -1126,12 +1259,14 @@ __INDEXATTR__;
 	 * Needs transaction
 	 *
 	 * @since 1.19
-	 * @return array how to search for table names schemas for the current user
+	 * @return array How to search for table names schemas for the current user
 	 */
 	function getSearchPath() {
 		$res = $this->query( "SHOW search_path", __METHOD__ );
 		$row = $this->fetchRow( $res );
+
 		/* PostgreSQL returns SHOW values as strings */
+
 		return explode( ",", $row[0] );
 	}
 
@@ -1140,7 +1275,7 @@ __INDEXATTR__;
 	 * Values may contain magic keywords like "$user"
 	 * @since 1.19
 	 *
-	 * @param $search_path array list of schemas to be searched by default
+	 * @param array $search_path List of schemas to be searched by default
 	 */
 	function setSearchPath( $search_path ) {
 		$this->query( "SET search_path = " . implode( ", ", $search_path ) );
@@ -1157,14 +1292,15 @@ __INDEXATTR__;
 	 * This will be also called by the installer after the schema is created
 	 *
 	 * @since 1.19
-	 * @param $desired_schema string
+	 *
+	 * @param string $desiredSchema
 	 */
-	function determineCoreSchema( $desired_schema ) {
+	function determineCoreSchema( $desiredSchema ) {
 		$this->begin( __METHOD__ );
-		if ( $this->schemaExists( $desired_schema ) ) {
-			if ( in_array( $desired_schema, $this->getSchemas() ) ) {
-				$this->mCoreSchema = $desired_schema;
-				wfDebug( "Schema \"" . $desired_schema . "\" already in the search path\n" );
+		if ( $this->schemaExists( $desiredSchema ) ) {
+			if ( in_array( $desiredSchema, $this->getSchemas() ) ) {
+				$this->mCoreSchema = $desiredSchema;
+				wfDebug( "Schema \"" . $desiredSchema . "\" already in the search path\n" );
 			} else {
 				/**
 				 * Prepend our schema (e.g. 'mediawiki') in front
@@ -1173,14 +1309,15 @@ __INDEXATTR__;
 				 */
 				$search_path = $this->getSearchPath();
 				array_unshift( $search_path,
-					$this->addIdentifierQuotes( $desired_schema ));
+					$this->addIdentifierQuotes( $desiredSchema ) );
 				$this->setSearchPath( $search_path );
-				$this->mCoreSchema = $desired_schema;
-				wfDebug( "Schema \"" . $desired_schema . "\" added to the search path\n" );
+				$this->mCoreSchema = $desiredSchema;
+				wfDebug( "Schema \"" . $desiredSchema . "\" added to the search path\n" );
 			}
 		} else {
 			$this->mCoreSchema = $this->getCurrentSchema();
-			wfDebug( "Schema \"" . $desired_schema . "\" not found, using current \"" . $this->mCoreSchema . "\"\n" );
+			wfDebug( "Schema \"" . $desiredSchema . "\" not found, using current \"" .
+				$this->mCoreSchema . "\"\n" );
 		}
 		/* Commit SET otherwise it will be rollbacked on error or IGNORE SELECT */
 		$this->commit( __METHOD__ );
@@ -1190,7 +1327,7 @@ __INDEXATTR__;
 	 * Return schema name fore core MediaWiki tables
 	 *
 	 * @since 1.19
-	 * @return string core schema name
+	 * @return string Core schema name
 	 */
 	function getCoreSchema() {
 		return $this->mCoreSchema;
@@ -1200,25 +1337,29 @@ __INDEXATTR__;
 	 * @return string Version information from the database
 	 */
 	function getServerVersion() {
-		if ( !isset( $this->numeric_version ) ) {
+		if ( !isset( $this->numericVersion ) ) {
 			$versionInfo = pg_version( $this->mConn );
 			if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
 				// Old client, abort install
-				$this->numeric_version = '7.3 or earlier';
+				$this->numericVersion = '7.3 or earlier';
 			} elseif ( isset( $versionInfo['server'] ) ) {
 				// Normal client
-				$this->numeric_version = $versionInfo['server'];
+				$this->numericVersion = $versionInfo['server'];
 			} else {
 				// Bug 16937: broken pgsql extension from PHP<5.3
-				$this->numeric_version = pg_parameter_status( $this->mConn, 'server_version' );
+				$this->numericVersion = pg_parameter_status( $this->mConn, 'server_version' );
 			}
 		}
-		return $this->numeric_version;
+
+		return $this->numericVersion;
 	}
 
 	/**
 	 * Query whether a given relation exists (in the given schema, or the
 	 * default mw one if not given)
+	 * @param string $table
+	 * @param array|string $types
+	 * @param bool|string $schema
 	 * @return bool
 	 */
 	function relationExists( $table, $types, $schema = false ) {
@@ -1231,17 +1372,21 @@ __INDEXATTR__;
 		$table = $this->realTableName( $table, 'raw' );
 		$etable = $this->addQuotes( $table );
 		$eschema = $this->addQuotes( $schema );
-		$SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
+		$sql = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
 			. "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
 			. "AND c.relkind IN ('" . implode( "','", $types ) . "')";
-		$res = $this->query( $SQL );
+		$res = $this->query( $sql );
 		$count = $res ? $res->numRows() : 0;
+
 		return (bool)$count;
 	}
 
 	/**
 	 * For backward compatibility, this function checks both tables and
 	 * views.
+	 * @param string $table
+	 * @param string $fname
+	 * @param bool|string $schema
 	 * @return bool
 	 */
 	function tableExists( $table, $fname = __METHOD__, $schema = false ) {
@@ -1271,6 +1416,7 @@ SQL;
 			return null;
 		}
 		$rows = $res->numRows();
+
 		return $rows;
 	}
 
@@ -1282,41 +1428,47 @@ SQL;
 				'schemaname' => $this->getCoreSchema()
 			)
 		);
+
 		return $exists === $rule;
 	}
 
 	function constraintExists( $table, $constraint ) {
-		$SQL = sprintf( "SELECT 1 FROM information_schema.table_constraints " .
-				"WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
+		$sql = sprintf( "SELECT 1 FROM information_schema.table_constraints " .
+			"WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
 			$this->addQuotes( $this->getCoreSchema() ),
 			$this->addQuotes( $table ),
 			$this->addQuotes( $constraint )
 		);
-		$res = $this->query( $SQL );
+		$res = $this->query( $sql );
 		if ( !$res ) {
 			return null;
 		}
 		$rows = $res->numRows();
+
 		return $rows;
 	}
 
 	/**
 	 * Query whether a given schema exists. Returns true if it does, false if it doesn't.
+	 * @param string $schema
 	 * @return bool
 	 */
 	function schemaExists( $schema ) {
 		$exists = $this->selectField( '"pg_catalog"."pg_namespace"', 1,
 			array( 'nspname' => $schema ), __METHOD__ );
+
 		return (bool)$exists;
 	}
 
 	/**
 	 * Returns true if a given role (i.e. user) exists, false otherwise.
+	 * @param string $roleName
 	 * @return bool
 	 */
 	function roleExists( $roleName ) {
 		$exists = $this->selectField( '"pg_catalog"."pg_roles"', 1,
 			array( 'rolname' => $roleName ), __METHOD__ );
+
 		return (bool)$exists;
 	}
 
@@ -1326,17 +1478,20 @@ SQL;
 
 	/**
 	 * pg_field_type() wrapper
+	 * @param ResultWrapper|resource $res ResultWrapper or PostgreSQL query result resource
+	 * @param int $index Field number, starting from 0
 	 * @return string
 	 */
 	function fieldType( $res, $index ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
+
 		return pg_field_type( $res, $index );
 	}
 
 	/**
-	 * @param $b
+	 * @param string $b
 	 * @return Blob
 	 */
 	function encodeBlob( $b ) {
@@ -1347,6 +1502,7 @@ SQL;
 		if ( $b instanceof Blob ) {
 			$b = $b->fetch();
 		}
+
 		return pg_unescape_bytea( $b );
 	}
 
@@ -1355,7 +1511,7 @@ SQL;
 	}
 
 	/**
-	 * @param $s null|bool|Blob
+	 * @param null|bool|Blob $s
 	 * @return int|string
 	 */
 	function addQuotes( $s ) {
@@ -1366,6 +1522,7 @@ SQL;
 		} elseif ( $s instanceof Blob ) {
 			return "'" . $s->fetch( $s ) . "'";
 		}
+
 		return "'" . pg_escape_string( $this->mConn, $s ) . "'";
 	}
 
@@ -1373,21 +1530,18 @@ SQL;
 	 * Postgres specific version of replaceVars.
 	 * Calls the parent version in Database.php
 	 *
-	 * @private
-	 *
 	 * @param string $ins SQL string, read from a stream (usually tables.sql)
-	 *
 	 * @return string SQL string
 	 */
 	protected function replaceVars( $ins ) {
 		$ins = parent::replaceVars( $ins );
 
-		if ( $this->numeric_version >= 8.3 ) {
+		if ( $this->numericVersion >= 8.3 ) {
 			// Thanks for not providing backwards-compatibility, 8.3
 			$ins = preg_replace( "/to_tsvector\s*\(\s*'default'\s*,/", 'to_tsvector(', $ins );
 		}
 
-		if ( $this->numeric_version <= 8.1 ) { // Our minimum version
+		if ( $this->numericVersion <= 8.1 ) { // Our minimum version
 			$ins = str_replace( 'USING gin', 'USING gist', $ins );
 		}
 
@@ -1397,10 +1551,8 @@ SQL;
 	/**
 	 * Various select options
 	 *
-	 * @private
-	 *
-	 * @param array $options an associative array of options to be turned into
-	 *              an SQL query, valid keys are listed in the function.
+	 * @param array $options An associative array of options to be turned into
+	 *   an SQL query, valid keys are listed in the function.
 	 * @return array
 	 */
 	function makeSelectOptions( $options ) {
@@ -1425,8 +1577,9 @@ SQL;
 		//}
 
 		if ( isset( $options['FOR UPDATE'] ) ) {
-			$postLimitTail .= ' FOR UPDATE OF ' . implode( ', ', $options['FOR UPDATE'] );
-		} else if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
+			$postLimitTail .= ' FOR UPDATE OF ' .
+				implode( ', ', array_map( array( &$this, 'tableName' ), $options['FOR UPDATE'] ) );
+		} elseif ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
 			$postLimitTail .= ' FOR UPDATE';
 		}
 
@@ -1437,9 +1590,6 @@ SQL;
 		return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
 	}
 
-	function setFakeMaster( $enabled = true ) {
-	}
-
 	function getDBname() {
 		return $this->mDBname;
 	}
@@ -1452,6 +1602,14 @@ SQL;
 		return implode( ' || ', $stringList );
 	}
 
+	public function buildGroupConcatField(
+		$delimiter, $table, $field, $conds = '', $options = array(), $join_conds = array()
+	) {
+		$fld = "array_to_string(array_agg($field)," . $this->addQuotes( $delimiter ) . ')';
+
+		return '(' . $this->selectSQLText( $table, $fld, $conds, null, array(), $join_conds ) . ')';
+	}
+
 	public function getSearchEngine() {
 		return 'SearchPostgres';
 	}
@@ -1461,11 +1619,11 @@ SQL;
 		if ( substr( $newLine, 0, 4 ) == '$mw$' ) {
 			if ( $this->delimiter ) {
 				$this->delimiter = false;
-			}
-			else {
+			} else {
 				$this->delimiter = ';';
 			}
 		}
+
 		return parent::streamStatementEnd( $sql, $newLine );
 	}
 
@@ -1473,9 +1631,9 @@ SQL;
 	 * Check to see if a named lock is available. This is non-blocking.
 	 * See http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
 	 *
-	 * @param string $lockName name of lock to poll
-	 * @param string $method name of method calling us
-	 * @return Boolean
+	 * @param string $lockName Name of lock to poll
+	 * @param string $method Name of method calling us
+	 * @return bool
 	 * @since 1.20
 	 */
 	public function lockIsFree( $lockName, $method ) {
@@ -1483,14 +1641,15 @@ SQL;
 		$result = $this->query( "SELECT (CASE(pg_try_advisory_lock($key))
 			WHEN 'f' THEN 'f' ELSE pg_advisory_unlock($key) END) AS lockstatus", $method );
 		$row = $this->fetchObject( $result );
+
 		return ( $row->lockstatus === 't' );
 	}
 
 	/**
 	 * See http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
-	 * @param $lockName string
-	 * @param $method string
-	 * @param $timeout int
+	 * @param string $lockName
+	 * @param string $method
+	 * @param int $timeout
 	 * @return bool
 	 */
 	public function lock( $lockName, $method, $timeout = 5 ) {
@@ -1506,19 +1665,22 @@ SQL;
 			}
 		}
 		wfDebug( __METHOD__ . " failed to acquire lock\n" );
+
 		return false;
 	}
 
 	/**
-	 * See http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKSFROM PG DOCS: http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
-	 * @param $lockName string
-	 * @param $method string
+	 * See http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKSFROM
+	 * PG DOCS: http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
+	 * @param string $lockName
+	 * @param string $method
 	 * @return bool
 	 */
 	public function unlock( $lockName, $method ) {
 		$key = $this->addQuotes( $this->bigintFromLockName( $lockName ) );
 		$result = $this->query( "SELECT pg_advisory_unlock($key) as lockstatus", $method );
 		$row = $this->fetchObject( $result );
+
 		return ( $row->lockstatus === 't' );
 	}
 
diff --git a/includes/db/DatabaseSqlite.php b/includes/db/DatabaseSqlite.php
index 3e034649..dd2e813e 100644
--- a/includes/db/DatabaseSqlite.php
+++ b/includes/db/DatabaseSqlite.php
@@ -26,38 +26,53 @@
  * @ingroup Database
  */
 class DatabaseSqlite extends DatabaseBase {
-
+	/** @var bool Whether full text is enabled */
 	private static $fulltextEnabled = null;
 
-	var $mAffectedRows;
-	var $mLastResult;
-	var $mDatabaseFile;
-	var $mName;
+	/** @var string File name for SQLite database file */
+	public $mDatabaseFile;
 
-	/**
-	 * @var PDO
-	 */
+	/** @var int The number of rows affected as an integer */
+	protected $mAffectedRows;
+
+	/** @var resource */
+	protected $mLastResult;
+
+	/** @var PDO */
 	protected $mConn;
 
-	/**
-	 * Constructor.
-	 * Parameters $server, $user and $password are not used.
-	 * @param $server string
-	 * @param $user string
-	 * @param $password string
-	 * @param $dbName string
-	 * @param $flags int
-	 */
-	function __construct( $server = false, $user = false, $password = false, $dbName = false, $flags = 0 ) {
-		$this->mName = $dbName;
-		parent::__construct( $server, $user, $password, $dbName, $flags );
+	/** @var FSLockManager (hopefully on the same server as the DB) */
+	protected $lockMgr;
+
+	function __construct( $p = null ) {
+		global $wgSharedDB, $wgSQLiteDataDir;
+
+		if ( !is_array( $p ) ) { // legacy calling pattern
+			wfDeprecated( __METHOD__ . " method called without parameter array.", "1.22" );
+			$args = func_get_args();
+			$p = array(
+				'host' => isset( $args[0] ) ? $args[0] : false,
+				'user' => isset( $args[1] ) ? $args[1] : false,
+				'password' => isset( $args[2] ) ? $args[2] : false,
+				'dbname' => isset( $args[3] ) ? $args[3] : false,
+				'flags' => isset( $args[4] ) ? $args[4] : 0,
+				'tablePrefix' => isset( $args[5] ) ? $args[5] : 'get from global',
+				'schema' => 'get from global',
+				'foreign' => isset( $args[6] ) ? $args[6] : false
+			);
+		}
+		$this->mDBname = $p['dbname'];
+		parent::__construct( $p );
 		// parent doesn't open when $user is false, but we can work with $dbName
-		if ( $dbName && !$this->isOpen() ) {
-			global $wgSharedDB;
-			if ( $this->open( $server, $user, $password, $dbName ) && $wgSharedDB ) {
-				$this->attachDatabase( $wgSharedDB );
+		if ( $p['dbname'] && !$this->isOpen() ) {
+			if ( $this->open( $p['host'], $p['user'], $p['password'], $p['dbname'] ) ) {
+				if ( $wgSharedDB ) {
+					$this->attachDatabase( $wgSharedDB );
+				}
 			}
 		}
+
+		$this->lockMgr = new FSLockManager( array( 'lockDirectory' => "$wgSQLiteDataDir/locks" ) );
 	}
 
 	/**
@@ -97,18 +112,20 @@ class DatabaseSqlite extends DatabaseBase {
 			throw new DBConnectionError( $this, "SQLite database not accessible" );
 		}
 		$this->openFile( $fileName );
+
 		return $this->mConn;
 	}
 
 	/**
 	 * Opens a database file
 	 *
-	 * @param $fileName string
-	 *
+	 * @param string $fileName
 	 * @throws DBConnectionError
 	 * @return PDO|bool SQL connection or false if failed
 	 */
 	function openFile( $fileName ) {
+		$err = false;
+
 		$this->mDatabaseFile = $fileName;
 		try {
 			if ( $this->mFlags & DBO_PERSISTENT ) {
@@ -120,18 +137,23 @@ class DatabaseSqlite extends DatabaseBase {
 		} catch ( PDOException $e ) {
 			$err = $e->getMessage();
 		}
+
 		if ( !$this->mConn ) {
 			wfDebug( "DB connection error: $err\n" );
 			throw new DBConnectionError( $this, $err );
 		}
+
 		$this->mOpened = !!$this->mConn;
 		# set error codes only, don't raise exceptions
 		if ( $this->mOpened ) {
 			$this->mConn->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_SILENT );
 			# Enforce LIKE to be case sensitive, just like MySQL
 			$this->query( 'PRAGMA case_sensitive_like = 1' );
-			return true;
+
+			return $this->mConn;
 		}
+
+		return false;
 	}
 
 	/**
@@ -140,6 +162,7 @@ class DatabaseSqlite extends DatabaseBase {
 	 */
 	protected function closeConnection() {
 		$this->mConn = null;
+
 		return true;
 	}
 
@@ -147,7 +170,7 @@ class DatabaseSqlite extends DatabaseBase {
 	 * Generates a database file name. Explicitly public for installer.
 	 * @param string $dir Directory where database resides
 	 * @param string $dbName Database name
-	 * @return String
+	 * @return string
 	 */
 	public static function generateFileName( $dir, $dbName ) {
 		return "$dir/$dbName.sqlite";
@@ -167,12 +190,13 @@ class DatabaseSqlite extends DatabaseBase {
 				self::$fulltextEnabled = stristr( $row['sql'], 'fts' ) !== false;
 			}
 		}
+
 		return self::$fulltextEnabled;
 	}
 
 	/**
 	 * Returns version of currently supported SQLite fulltext search module or false if none present.
-	 * @return String
+	 * @return string
 	 */
 	static function getFulltextSearchModule() {
 		static $cachedResult = null;
@@ -188,6 +212,7 @@ class DatabaseSqlite extends DatabaseBase {
 			$cachedResult = 'FTS3';
 		}
 		$db->close();
+
 		return $cachedResult;
 	}
 
@@ -195,10 +220,11 @@ class DatabaseSqlite extends DatabaseBase {
 	 * Attaches external database to our connection, see http://sqlite.org/lang_attach.html
 	 * for details.
 	 *
-	 * @param string $name database name to be used in queries like SELECT foo FROM dbname.table
-	 * @param string $file database file name. If omitted, will be generated using $name and $wgSQLiteDataDir
-	 * @param string $fname calling function name
-	 *
+	 * @param string $name Database name to be used in queries like
+	 *   SELECT foo FROM dbname.table
+	 * @param bool|string $file Database file name. If omitted, will be generated
+	 *   using $name and $wgSQLiteDataDir
+	 * @param string $fname Calling function name
 	 * @return ResultWrapper
 	 */
 	function attachDatabase( $name, $file = false, $fname = __METHOD__ ) {
@@ -207,14 +233,14 @@ class DatabaseSqlite extends DatabaseBase {
 			$file = self::generateFileName( $wgSQLiteDataDir, $name );
 		}
 		$file = $this->addQuotes( $file );
+
 		return $this->query( "ATTACH DATABASE $file AS $name", $fname );
 	}
 
 	/**
 	 * @see DatabaseBase::isWriteQuery()
 	 *
-	 * @param $sql string
-	 *
+	 * @param string $sql
 	 * @return bool
 	 */
 	function isWriteQuery( $sql ) {
@@ -224,9 +250,8 @@ class DatabaseSqlite extends DatabaseBase {
 	/**
 	 * SQLite doesn't allow buffered results or data seeking etc, so we'll use fetchAll as the result
 	 *
-	 * @param $sql string
-	 *
-	 * @return ResultWrapper
+	 * @param string $sql
+	 * @return bool|ResultWrapper
 	 */
 	protected function doQuery( $sql ) {
 		$res = $this->mConn->query( $sql );
@@ -237,11 +262,12 @@ class DatabaseSqlite extends DatabaseBase {
 			$this->mAffectedRows = $r->rowCount();
 			$res = new ResultWrapper( $this, $r->fetchAll() );
 		}
+
 		return $res;
 	}
 
 	/**
-	 * @param $res ResultWrapper
+	 * @param ResultWrapper|mixed $res
 	 */
 	function freeResult( $res ) {
 		if ( $res instanceof ResultWrapper ) {
@@ -252,8 +278,8 @@ class DatabaseSqlite extends DatabaseBase {
 	}
 
 	/**
-	 * @param $res ResultWrapper
-	 * @return object|bool
+	 * @param ResultWrapper|array $res
+	 * @return stdClass|bool
 	 */
 	function fetchObject( $res ) {
 		if ( $res instanceof ResultWrapper ) {
@@ -274,11 +300,12 @@ class DatabaseSqlite extends DatabaseBase {
 
 			return $obj;
 		}
+
 		return false;
 	}
 
 	/**
-	 * @param $res ResultWrapper
+	 * @param ResultWrapper|mixed $res
 	 * @return array|bool
 	 */
 	function fetchRow( $res ) {
@@ -290,51 +317,61 @@ class DatabaseSqlite extends DatabaseBase {
 		$cur = current( $r );
 		if ( is_array( $cur ) ) {
 			next( $r );
+
 			return $cur;
 		}
+
 		return false;
 	}
 
 	/**
 	 * The PDO::Statement class implements the array interface so count() will work
 	 *
-	 * @param $res ResultWrapper
-	 *
+	 * @param ResultWrapper|array $res
 	 * @return int
 	 */
 	function numRows( $res ) {
 		$r = $res instanceof ResultWrapper ? $res->result : $res;
+
 		return count( $r );
 	}
 
 	/**
-	 * @param $res ResultWrapper
+	 * @param ResultWrapper $res
 	 * @return int
 	 */
 	function numFields( $res ) {
 		$r = $res instanceof ResultWrapper ? $res->result : $res;
-		return is_array( $r ) ? count( $r[0] ) : 0;
+		if ( is_array( $r ) && count( $r ) > 0 ) {
+			// The size of the result array is twice the number of fields. (Bug: 65578)
+			return count( $r[0] ) / 2;
+		} else {
+			// If the result is empty return 0
+			return 0;
+		}
 	}
 
 	/**
-	 * @param $res ResultWrapper
-	 * @param $n
+	 * @param ResultWrapper $res
+	 * @param int $n
 	 * @return bool
 	 */
 	function fieldName( $res, $n ) {
 		$r = $res instanceof ResultWrapper ? $res->result : $res;
 		if ( is_array( $r ) ) {
 			$keys = array_keys( $r[0] );
+
 			return $keys[$n];
 		}
+
 		return false;
 	}
 
 	/**
 	 * Use MySQL's naming (accounts for prefix etc) but remove surrounding backticks
 	 *
-	 * @param $name
-	 * @param $format String
+	 * @param string $name
+	 * @param string $format
 	 * @return string
 	 */
 	function tableName( $name, $format = 'quoted' ) {
@@ -342,14 +379,14 @@ class DatabaseSqlite extends DatabaseBase {
 		if ( strpos( $name, 'sqlite_' ) === 0 ) {
 			return $name;
 		}
+
 		return str_replace( '"', '', parent::tableName( $name, $format ) );
 	}
 
 	/**
 	 * Index names have DB scope
 	 *
-	 * @param $index string
-	 *
+	 * @param string $index
 	 * @return string
 	 */
 	function indexName( $index ) {
@@ -367,8 +404,8 @@ class DatabaseSqlite extends DatabaseBase {
 	}
 
 	/**
-	 * @param $res ResultWrapper
-	 * @param $row
+	 * @param ResultWrapper|array $res
+	 * @param int $row
 	 */
 	function dataSeek( $res, $row ) {
 		if ( $res instanceof ResultWrapper ) {
@@ -392,6 +429,7 @@ class DatabaseSqlite extends DatabaseBase {
 			return "Cannot return last error, no db connection";
 		}
 		$e = $this->mConn->errorInfo();
+
 		return isset( $e[2] ) ? $e[2] : '';
 	}
 
@@ -403,6 +441,7 @@ class DatabaseSqlite extends DatabaseBase {
 			return "Cannot return last error, no db connection";
 		} else {
 			$info = $this->mConn->errorInfo();
+
 			return $info[1];
 		}
 	}
@@ -419,6 +458,9 @@ class DatabaseSqlite extends DatabaseBase {
 	 * Returns false if the index does not exist
 	 * - if errors are explicitly ignored, returns NULL on failure
 	 *
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return array
 	 */
 	function indexInfo( $table, $index, $fname = __METHOD__ ) {
@@ -434,13 +476,14 @@ class DatabaseSqlite extends DatabaseBase {
 		foreach ( $res as $row ) {
 			$info[] = $row->name;
 		}
+
 		return $info;
 	}
 
 	/**
-	 * @param $table
-	 * @param $index
-	 * @param $fname string
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
 	 * @return bool|null
 	 */
 	function indexUnique( $table, $index, $fname = __METHOD__ ) {
@@ -460,14 +503,14 @@ class DatabaseSqlite extends DatabaseBase {
 		}
 		$firstPart = substr( $row->sql, 0, $indexPos );
 		$options = explode( ' ', $firstPart );
+
 		return in_array( 'UNIQUE', $options );
 	}
 
 	/**
 	 * Filter the options used in SELECT statements
 	 *
-	 * @param $options array
-	 *
+	 * @param array $options
 	 * @return array
 	 */
 	function makeSelectOptions( $options ) {
@@ -476,20 +519,23 @@ class DatabaseSqlite extends DatabaseBase {
 				$options[$k] = '';
 			}
 		}
+
 		return parent::makeSelectOptions( $options );
 	}
 
 	/**
-	 * @param $options array
+	 * @param array $options
 	 * @return string
 	 */
-	function makeUpdateOptions( $options ) {
+	protected function makeUpdateOptionsArray( $options ) {
+		$options = parent::makeUpdateOptionsArray( $options );
 		$options = self::fixIgnore( $options );
-		return parent::makeUpdateOptions( $options );
+
+		return $options;
 	}
 
 	/**
-	 * @param $options array
+	 * @param array $options
 	 * @return array
 	 */
 	static function fixIgnore( $options ) {
@@ -499,20 +545,26 @@ class DatabaseSqlite extends DatabaseBase {
 				$options[$k] = 'OR IGNORE';
 			}
 		}
+
 		return $options;
 	}
 
 	/**
-	 * @param $options array
+	 * @param array $options
 	 * @return string
 	 */
 	function makeInsertOptions( $options ) {
 		$options = self::fixIgnore( $options );
+
 		return parent::makeInsertOptions( $options );
 	}
 
 	/**
 	 * Based on generic method (parent) with some prior SQLite-sepcific adjustments
+	 * @param string $table
+	 * @param array $a
+	 * @param string $fname
+	 * @param array $options
 	 * @return bool
 	 */
 	function insert( $table, $a, $fname = __METHOD__, $options = array() ) {
@@ -536,10 +588,10 @@ class DatabaseSqlite extends DatabaseBase {
 	}
 
 	/**
-	 * @param $table
-	 * @param $uniqueIndexes
-	 * @param $rows
-	 * @param $fname string
+	 * @param string $table
+	 * @param array $uniqueIndexes Unused
+	 * @param string|array $rows
+	 * @param string $fname
 	 * @return bool|ResultWrapper
 	 */
 	function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
@@ -566,6 +618,8 @@ class DatabaseSqlite extends DatabaseBase {
 	 * Returns the size of a text field, or -1 for "unlimited"
 	 * In SQLite this is SQLITE_MAX_LENGTH, by default 1GB. No way to query it though.
 	 *
+	 * @param string $table
+	 * @param string $field
 	 * @return int
 	 */
 	function textFieldSize( $table, $field ) {
@@ -580,12 +634,13 @@ class DatabaseSqlite extends DatabaseBase {
 	}
 
 	/**
-	 * @param $sqls
-	 * @param $all
+	 * @param string $sqls
+	 * @param bool $all Whether to "UNION ALL" or not
 	 * @return string
 	 */
 	function unionQueries( $sqls, $all ) {
 		$glue = $all ? ' UNION ALL ' : ' UNION ';
+
 		return implode( $glue, $sqls );
 	}
 
@@ -611,7 +666,7 @@ class DatabaseSqlite extends DatabaseBase {
 	}
 
 	/**
-	 * @return string wikitext of a link to the server software's web site
+	 * @return string Wikitext of a link to the server software's web site
 	 */
 	public function getSoftwareLink() {
 		return "[{{int:version-db-sqlite-url}} SQLite]";
@@ -622,6 +677,7 @@ class DatabaseSqlite extends DatabaseBase {
 	 */
 	function getServerVersion() {
 		$ver = $this->mConn->getAttribute( PDO::ATTR_SERVER_VERSION );
+
 		return $ver;
 	}
 
@@ -629,15 +685,17 @@ class DatabaseSqlite extends DatabaseBase {
 	 * @return string User-friendly database information
 	 */
 	public function getServerInfo() {
-		return wfMessage( self::getFulltextSearchModule() ? 'sqlite-has-fts' : 'sqlite-no-fts', $this->getServerVersion() )->text();
+		return wfMessage( self::getFulltextSearchModule()
+			? 'sqlite-has-fts'
+			: 'sqlite-no-fts', $this->getServerVersion() )->text();
 	}
 
 	/**
 	 * Get information about a given field
 	 * Returns false if the field does not exist.
 	 *
-	 * @param $table string
-	 * @param $field string
+	 * @param string $table
+	 * @param string $field
 	 * @return SQLiteField|bool False on failure
 	 */
 	function fieldInfo( $table, $field ) {
@@ -649,6 +707,7 @@ class DatabaseSqlite extends DatabaseBase {
 				return new SQLiteField( $row, $tableName );
 			}
 		}
+
 		return false;
 	}
 
@@ -685,15 +744,15 @@ class DatabaseSqlite extends DatabaseBase {
 	}
 
 	/**
-	 * @param $s string
+	 * @param string $s
 	 * @return string
 	 */
 	function strencode( $s ) {
-		return substr( $this->addQuotes( $s ), 1, - 1 );
+		return substr( $this->addQuotes( $s ), 1, -1 );
 	}
 
 	/**
-	 * @param $b
+	 * @param string $b
 	 * @return Blob
 	 */
 	function encodeBlob( $b ) {
@@ -701,18 +760,19 @@ class DatabaseSqlite extends DatabaseBase {
 	}
 
 	/**
-	 * @param $b Blob|string
+	 * @param Blob|string $b
 	 * @return string
 	 */
 	function decodeBlob( $b ) {
 		if ( $b instanceof Blob ) {
 			$b = $b->fetch();
 		}
+
 		return $b;
 	}
 
 	/**
-	 * @param $s Blob|string
+	 * @param Blob|string $s
 	 * @return string
 	 */
 	function addQuotes( $s ) {
@@ -741,6 +801,7 @@ class DatabaseSqlite extends DatabaseBase {
 		if ( count( $params ) > 0 && is_array( $params[0] ) ) {
 			$params = $params[0];
 		}
+
 		return parent::buildLike( $params ) . "ESCAPE '\' ";
 	}
 
@@ -753,16 +814,18 @@ class DatabaseSqlite extends DatabaseBase {
 
 	/**
 	 * No-op version of deadlockLoop
+	 *
 	 * @return mixed
 	 */
 	public function deadlockLoop( /*...*/ ) {
 		$args = func_get_args();
 		$function = array_shift( $args );
+
 		return call_user_func_array( $function, $args );
 	}
 
 	/**
-	 * @param $s string
+	 * @param string $s
 	 * @return string
 	 */
 	protected function replaceVars( $s ) {
@@ -777,7 +840,11 @@ class DatabaseSqlite extends DatabaseBase {
 			// INT -> INTEGER
 			$s = preg_replace( '/\b(tiny|small|medium|big|)int(\s*\(\s*\d+\s*\)|\b)/i', 'INTEGER', $s );
 			// floating point types -> REAL
-			$s = preg_replace( '/\b(float|double(\s+precision)?)(\s*\(\s*\d+\s*(,\s*\d+\s*)?\)|\b)/i', 'REAL', $s );
+			$s = preg_replace(
+				'/\b(float|double(\s+precision)?)(\s*\(\s*\d+\s*(,\s*\d+\s*)?\)|\b)/i',
+				'REAL',
+				$s
+			);
 			// varchar -> TEXT
 			$s = preg_replace( '/\b(var)?char\s*\(.*?\)/i', 'TEXT', $s );
 			// TEXT normalization
@@ -803,37 +870,73 @@ class DatabaseSqlite extends DatabaseBase {
 			$s = preg_replace( '/\(\d+\)/', '', $s );
 			// No FULLTEXT
 			$s = preg_replace( '/\bfulltext\b/i', '', $s );
+		} elseif ( preg_match( '/^\s*DROP INDEX/i', $s ) ) {
+			// DROP INDEX is database-wide, not table-specific, so no ON <table> clause.
+			$s = preg_replace( '/\sON\s+[^\s]*/i', '', $s );
+		} elseif ( preg_match( '/^\s*INSERT IGNORE\b/i', $s ) ) {
+			// INSERT IGNORE --> INSERT OR IGNORE
+			$s = preg_replace( '/^\s*INSERT IGNORE\b/i', 'INSERT OR IGNORE', $s );
 		}
+
 		return $s;
 	}
 
+	public function lock( $lockName, $method, $timeout = 5 ) {
+		global $wgSQLiteDataDir;
+
+		if ( !is_dir( "$wgSQLiteDataDir/locks" ) ) { // create dir as needed
+			if ( !is_writable( $wgSQLiteDataDir ) || !mkdir( "$wgSQLiteDataDir/locks" ) ) {
+				throw new DBError( "Cannot create directory \"$wgSQLiteDataDir/locks\"." );
+			}
+		}
+
+		return $this->lockMgr->lock( array( $lockName ), LockManager::LOCK_EX, $timeout )->isOK();
+	}
+
+	public function unlock( $lockName, $method ) {
+		return $this->lockMgr->unlock( array( $lockName ), LockManager::LOCK_EX )->isOK();
+	}
+
 	/**
 	 * Build a concatenation list to feed into a SQL query
 	 *
-	 * @param $stringList array
-	 *
+	 * @param string[] $stringList
 	 * @return string
 	 */
 	function buildConcat( $stringList ) {
 		return '(' . implode( ') || (', $stringList ) . ')';
 	}
 
+	public function buildGroupConcatField(
+		$delim, $table, $field, $conds = '', $join_conds = array()
+	) {
+		$fld = "group_concat($field," . $this->addQuotes( $delim ) . ')';
+
+		return '(' . $this->selectSQLText( $table, $fld, $conds, null, array(), $join_conds ) . ')';
+	}
+
 	/**
 	 * @throws MWException
-	 * @param $oldName
-	 * @param $newName
-	 * @param $temporary bool
-	 * @param $fname string
+	 * @param string $oldName
+	 * @param string $newName
+	 * @param bool $temporary
+	 * @param string $fname
 	 * @return bool|ResultWrapper
 	 */
 	function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
-		$res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name=" . $this->addQuotes( $oldName ) . " AND type='table'", $fname );
+		$res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name=" .
+			$this->addQuotes( $oldName ) . " AND type='table'", $fname );
 		$obj = $this->fetchObject( $res );
 		if ( !$obj ) {
 			throw new MWException( "Couldn't retrieve structure for table $oldName" );
 		}
 		$sql = $obj->sql;
-		$sql = preg_replace( '/(?<=\W)"?' . preg_quote( trim( $this->addIdentifierQuotes( $oldName ), '"' ) ) . '"?(?=\W)/', $this->addIdentifierQuotes( $newName ), $sql, 1 );
+		$sql = preg_replace(
+			'/(?<=\W)"?' . preg_quote( trim( $this->addIdentifierQuotes( $oldName ), '"' ) ) . '"?(?=\W)/',
+			$this->addIdentifierQuotes( $newName ),
+			$sql,
+			1
+		);
 		if ( $temporary ) {
 			if ( preg_match( '/^\\s*CREATE\\s+VIRTUAL\\s+TABLE\b/i', $sql ) ) {
 				wfDebug( "Table $oldName is virtual, can't create a temporary duplicate.\n" );
@@ -841,6 +944,7 @@ class DatabaseSqlite extends DatabaseBase {
 				$sql = str_replace( 'CREATE TABLE', 'CREATE TEMPORARY TABLE', $sql );
 			}
 		}
+
 		return $this->query( $sql, $fname );
 	}
 
@@ -848,7 +952,7 @@ class DatabaseSqlite extends DatabaseBase {
 	 * List all tables on the database
 	 *
 	 * @param string $prefix Only show tables with this prefix, e.g. mw_
-	 * @param string $fname calling function name
+	 * @param string $fname Calling function name
 	 *
 	 * @return array
 	 */
@@ -869,13 +973,11 @@ class DatabaseSqlite extends DatabaseBase {
 				if ( strpos( $table, 'sqlite_' ) !== 0 ) {
 					$endArray[] = $table;
 				}
-
 			}
 		}
 
 		return $endArray;
 	}
-
 } // end DatabaseSqlite class
 
 /**
@@ -895,6 +997,7 @@ class DatabaseSqliteStandalone extends DatabaseSqlite {
  */
 class SQLiteField implements Field {
 	private $info, $tableName;
+
 	function __construct( $info, $tableName ) {
 		$this->info = $info;
 		$this->tableName = $tableName;
@@ -915,6 +1018,7 @@ class SQLiteField implements Field {
 				return str_replace( "''", "'", $this->info->dflt_value );
 			}
 		}
+
 		return $this->info->dflt_value;
 	}
 
@@ -928,5 +1032,4 @@ class SQLiteField implements Field {
 	function type() {
 		return $this->info->type;
 	}
-
 } // end SQLiteField
diff --git a/includes/db/DatabaseUtility.php b/includes/db/DatabaseUtility.php
index de58bab6..c1e80d33 100644
--- a/includes/db/DatabaseUtility.php
+++ b/includes/db/DatabaseUtility.php
@@ -51,7 +51,8 @@ class DBObject {
  * This allows us to distinguish a blob from a normal string and an array of strings
  */
 class Blob {
-	private $mData;
+	/** @var string */
+	protected $mData;
 
 	function __construct( $data ) {
 		$this->mData = $data;
@@ -97,13 +98,23 @@ interface Field {
  * @ingroup Database
  */
 class ResultWrapper implements Iterator {
-	var $db, $result, $pos = 0, $currentRow = null;
+	/** @var resource */
+	public $result;
+
+	/** @var DatabaseBase */
+	protected $db;
+
+	/** @var int */
+	protected $pos = 0;
+
+	/** @var object|null */
+	protected $currentRow = null;
 
 	/**
 	 * Create a new result object from a result resource and a Database object
 	 *
 	 * @param DatabaseBase $database
-	 * @param resource $result
+	 * @param resource|ResultWrapper $result
 	 */
 	function __construct( $database, $result ) {
 		$this->db = $database;
@@ -118,7 +129,7 @@ class ResultWrapper implements Iterator {
 	/**
 	 * Get the number of rows in a result object
 	 *
-	 * @return integer
+	 * @return int
 	 */
 	function numRows() {
 		return $this->db->numRows( $this );
@@ -129,7 +140,7 @@ class ResultWrapper implements Iterator {
 	 * Fields can be retrieved with $row->fieldname, with fields acting like
 	 * member variables.
 	 *
-	 * @return object
+	 * @return stdClass
 	 * @throws DBUnexpectedError Thrown if the database returns an error
 	 */
 	function fetchObject() {
@@ -140,7 +151,7 @@ class ResultWrapper implements Iterator {
 	 * Fetch the next row from the given result object, in associative array
 	 * form. Fields are retrieved with $row['fieldname'].
 	 *
-	 * @return Array
+	 * @return array
 	 * @throws DBUnexpectedError Thrown if the database returns an error
 	 */
 	function fetchRow() {
@@ -160,14 +171,14 @@ class ResultWrapper implements Iterator {
 	 * Change the position of the cursor in a result object.
 	 * See mysql_data_seek()
 	 *
-	 * @param $row integer
+	 * @param int $row
 	 */
 	function seek( $row ) {
 		$this->db->dataSeek( $this, $row );
 	}
 
-	/*********************
-	 * Iterator functions
+	/*
+	 * ======= Iterator functions =======
 	 * Note that using these in combination with the non-iterator functions
 	 * above may cause rows to be skipped or repeated.
 	 */
@@ -181,12 +192,13 @@ class ResultWrapper implements Iterator {
 	}
 
 	/**
-	 * @return int
+	 * @return stdClass|array|bool
 	 */
 	function current() {
 		if ( is_null( $this->currentRow ) ) {
 			$this->next();
 		}
+
 		return $this->currentRow;
 	}
 
@@ -198,11 +210,12 @@ class ResultWrapper implements Iterator {
 	}
 
 	/**
-	 * @return int
+	 * @return stdClass
 	 */
 	function next() {
 		$this->pos++;
 		$this->currentRow = $this->fetchObject();
+
 		return $this->currentRow;
 	}
 
@@ -219,10 +232,17 @@ class ResultWrapper implements Iterator {
  * doesn't go anywhere near an actual database.
  */
 class FakeResultWrapper extends ResultWrapper {
-	var $result = array();
-	var $db = null; // And it's going to stay that way :D
-	var $pos = 0;
-	var $currentRow = null;
+	/** @var array */
+	public $result = array();
+
+	/** @var null And it's going to stay that way :D */
+	protected $db = null;
+
+	/** @var int */
+	protected $pos = 0;
+
+	/** @var array|stdClass|bool */
+	protected $currentRow = null;
 
 	function __construct( $array ) {
 		$this->result = $array;
@@ -235,6 +255,9 @@ class FakeResultWrapper extends ResultWrapper {
 		return count( $this->result );
 	}
 
+	/**
+	 * @return array|bool
+	 */
 	function fetchRow() {
 		if ( $this->pos < count( $this->result ) ) {
 			$this->currentRow = $this->result[$this->pos];
@@ -256,7 +279,10 @@ class FakeResultWrapper extends ResultWrapper {
 	function free() {
 	}
 
-	// Callers want to be able to access fields with $this->fieldName
+	/**
+	 * Callers want to be able to access fields with $this->fieldName
+	 * @return bool|stdClass
+	 */
 	function fetchObject() {
 		$this->fetchRow();
 		if ( $this->currentRow ) {
@@ -271,16 +297,21 @@ class FakeResultWrapper extends ResultWrapper {
 		$this->currentRow = null;
 	}
 
+	/**
+	 * @return bool|stdClass
+	 */
 	function next() {
 		return $this->fetchObject();
 	}
 }
 
 /**
- * Used by DatabaseBase::buildLike() to represent characters that have special meaning in SQL LIKE clauses
- * and thus need no escaping. Don't instantiate it manually, use DatabaseBase::anyChar() and anyString() instead.
+ * Used by DatabaseBase::buildLike() to represent characters that have special
+ * meaning in SQL LIKE clauses and thus need no escaping. Don't instantiate it
+ * manually, use DatabaseBase::anyChar() and anyString() instead.
  */
 class LikeMatch {
+	/** @var string */
 	private $str;
 
 	/**
@@ -295,7 +326,7 @@ class LikeMatch {
 	/**
 	 * Return the original stored string.
 	 *
-	 * @return String
+	 * @return string
 	 */
 	public function toString() {
 		return $this->str;
@@ -304,6 +335,8 @@ class LikeMatch {
 
 /**
  * An object representing a master or slave position in a replicated setup.
+ *
+ * The implementation details of this opaque type are up to the database subclass.
  */
 interface DBMasterPos {
 }
diff --git a/includes/db/IORMRow.php b/includes/db/IORMRow.php
index 39411791..c66cddfd 100644
--- a/includes/db/IORMRow.php
+++ b/includes/db/IORMRow.php
@@ -32,7 +32,6 @@
  */
 
 interface IORMRow {
-
 	/**
 	 * Load the specified fields from the database.
 	 *
@@ -40,8 +39,8 @@ interface IORMRow {
 	 * @deprecated since 1.22
 	 *
 	 * @param array|null $fields
-	 * @param boolean $override
-	 * @param boolean $skipLoaded
+	 * @param bool $override
+	 * @param bool $skipLoaded
 	 *
 	 * @return bool Success indicator
 	 */
@@ -86,7 +85,7 @@ interface IORMRow {
 	 *
 	 * @since 1.20
 	 *
-	 * @return integer|null
+	 * @return int|null
 	 */
 	public function getId();
 
@@ -95,7 +94,7 @@ interface IORMRow {
 	 *
 	 * @since 1.20
 	 *
-	 * @param integer|null $id
+	 * @param int|null $id
 	 */
 	public function setId( $id );
 
@@ -106,7 +105,7 @@ interface IORMRow {
 	 *
 	 * @param string $name
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function hasField( $name );
 
@@ -115,7 +114,7 @@ interface IORMRow {
 	 *
 	 * @since 1.20
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function hasIdField();
 
@@ -125,7 +124,7 @@ interface IORMRow {
 	 * @since 1.20
 	 *
 	 * @param array $fields The fields to set
-	 * @param boolean $override Override already set fields with the provided values?
+	 * @param bool $override Override already set fields with the provided values?
 	 */
 	public function setFields( array $fields, $override = true );
 
@@ -136,7 +135,7 @@ interface IORMRow {
 	 * @since 1.20
 	 *
 	 * @param null|array $fields
-	 * @param boolean $incNullId
+	 * @param bool $incNullId
 	 *
 	 * @return array
 	 */
@@ -148,7 +147,7 @@ interface IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @param boolean $override
+	 * @param bool $override
 	 */
 	public function loadDefaults( $override = true );
 
@@ -161,7 +160,7 @@ interface IORMRow {
 	 * @param string|null $functionName
 	 * @deprecated since 1.22
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function save( $functionName = null );
 
@@ -171,7 +170,7 @@ interface IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function remove();
 
@@ -214,9 +213,9 @@ interface IORMRow {
 	 * @deprecated since 1.22
 	 *
 	 * @param string $field
-	 * @param integer $amount
+	 * @param int $amount
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function addToField( $field, $amount );
 
@@ -245,7 +244,7 @@ interface IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @param boolean $update
+	 * @param bool $update
 	 */
 	public function setUpdateSummaries( $update );
 
@@ -255,7 +254,7 @@ interface IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @param boolean $summaryMode
+	 * @param bool $summaryMode
 	 */
 	public function setSummaryMode( $summaryMode );
 
@@ -268,5 +267,4 @@ interface IORMRow {
 	 * @return IORMTable
 	 */
 	public function getTable();
-
 }
diff --git a/includes/db/IORMTable.php b/includes/db/IORMTable.php
index 36865655..4dc693ac 100644
--- a/includes/db/IORMTable.php
+++ b/includes/db/IORMTable.php
@@ -28,7 +28,6 @@
  */
 
 interface IORMTable {
-
 	/**
 	 * Returns the name of the database table objects of this type are stored in.
 	 *
@@ -63,8 +62,9 @@ interface IORMTable {
 	 * * array
 	 * * blob
 	 *
-	 * TODO: get rid of the id field. Every row instance needs to have
-	 * one so this is just causing hassle at various locations by requiring an extra check for field name.
+	 * @todo Get rid of the id field. Every row instance needs to have one so
+	 *   this is just causing hassle at various locations by requiring an extra
+	 *   check for field name.
 	 *
 	 * @since 1.20
 	 *
@@ -107,10 +107,10 @@ interface IORMTable {
 	 * @param string|null $functionName
 	 *
 	 * @return ORMResult The result set
-	 * @throws DBQueryError if the query failed (even if the database was in ignoreErrors mode)
+	 * @throws DBQueryError If the query failed (even if the database was in ignoreErrors mode)
 	 */
 	public function select( $fields = null, array $conditions = array(),
-							array $options = array(), $functionName = null );
+		array $options = array(), $functionName = null );
 
 	/**
 	 * Selects the the specified fields of the records matching the provided
@@ -123,10 +123,10 @@ interface IORMTable {
 	 * @param array $options
 	 * @param string|null $functionName
 	 *
-	 * @return array of self
+	 * @return array Array of self
 	 */
 	public function selectObjects( $fields = null, array $conditions = array(),
-								   array $options = array(), $functionName = null );
+		array $options = array(), $functionName = null );
 
 	/**
 	 * Do the actual select.
@@ -139,10 +139,10 @@ interface IORMTable {
 	 * @param null|string $functionName
 	 *
 	 * @return ResultWrapper
-	 * @throws DBQueryError if the query failed (even if the database was in ignoreErrors mode)
+	 * @throws DBQueryError If the query failed (even if the database was in ignoreErrors mode)
 	 */
 	public function rawSelect( $fields = null, array $conditions = array(),
-							   array $options = array(), $functionName = null );
+		array $options = array(), $functionName = null );
 
 	/**
 	 * Selects the the specified fields of the records matching the provided
@@ -161,13 +161,13 @@ interface IORMTable {
 	 * @param array|string|null $fields
 	 * @param array $conditions
 	 * @param array $options
-	 * @param boolean $collapse Set to false to always return each result row as associative array.
+	 * @param bool $collapse Set to false to always return each result row as associative array.
 	 * @param string|null $functionName
 	 *
-	 * @return array of array
+	 * @return array Array of array
 	 */
 	public function selectFields( $fields = null, array $conditions = array(),
-								  array $options = array(), $collapse = true, $functionName = null );
+		array $options = array(), $collapse = true, $functionName = null );
 
 	/**
 	 * Selects the the specified fields of the first matching record.
@@ -183,7 +183,7 @@ interface IORMTable {
 	 * @return IORMRow|bool False on failure
 	 */
 	public function selectRow( $fields = null, array $conditions = array(),
-							   array $options = array(), $functionName = null );
+		array $options = array(), $functionName = null );
 
 	/**
 	 * Selects the the specified fields of the records matching the provided
@@ -199,7 +199,7 @@ interface IORMTable {
 	 * @return ResultWrapper
 	 */
 	public function rawSelectRow( array $fields, array $conditions = array(),
-								  array $options = array(), $functionName = null );
+		array $options = array(), $functionName = null );
 
 	/**
 	 * Selects the the specified fields of the first record matching the provided
@@ -213,13 +213,13 @@ interface IORMTable {
 	 * @param array|string|null $fields
 	 * @param array $conditions
 	 * @param array $options
-	 * @param boolean $collapse Set to false to always return each result row as associative array.
+	 * @param bool $collapse Set to false to always return each result row as associative array.
 	 * @param string|null $functionName
 	 *
 	 * @return mixed|array|bool False on failure
 	 */
 	public function selectFieldsRow( $fields = null, array $conditions = array(),
-									 array $options = array(), $collapse = true, $functionName = null );
+		array $options = array(), $collapse = true, $functionName = null );
 
 	/**
 	 * Returns if there is at least one record matching the provided conditions.
@@ -229,7 +229,7 @@ interface IORMTable {
 	 *
 	 * @param array $conditions
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function has( array $conditions = array() );
 
@@ -238,7 +238,7 @@ interface IORMTable {
 	 *
 	 * @since 1.21
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function exists();
 
@@ -254,7 +254,7 @@ interface IORMTable {
 	 * @param array $conditions
 	 * @param array $options
 	 *
-	 * @return integer
+	 * @return int
 	 */
 	public function count( array $conditions = array(), array $options = array() );
 
@@ -266,7 +266,7 @@ interface IORMTable {
 	 * @param array $conditions
 	 * @param string|null $functionName
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function delete( array $conditions, $functionName = null );
 
@@ -275,8 +275,8 @@ interface IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @param boolean $requireParams
-	 * @param boolean $setDefaults
+	 * @param bool $requireParams
+	 * @param bool $setDefaults
 	 *
 	 * @return array
 	 */
@@ -298,14 +298,14 @@ interface IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @return integer DB_ enum
+	 * @return int DB_ enum
 	 */
 	public function getReadDb();
 
 	/**
 	 * Set the database type to use for read operations.
 	 *
-	 * @param integer $db
+	 * @param int $db
 	 *
 	 * @since 1.20
 	 */
@@ -316,14 +316,16 @@ interface IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @return String|bool The target wiki, in a form that  LBFactory understands (or false if the local wiki is used)
+	 * @return string|bool The target wiki, in a form that LBFactory
+	 *   understands (or false if the local wiki is used)
 	 */
 	public function getTargetWiki();
 
 	/**
 	 * Set the ID of the any foreign wiki to use as a target for database operations
 	 *
-	 * @param string|bool $wiki The target wiki, in a form that  LBFactory understands (or false if the local wiki shall be used)
+	 * @param string|bool $wiki The target wiki, in a form that LBFactory
+	 *   understands (or false if the local wiki shall be used)
 	 *
 	 * @since 1.20
 	 */
@@ -370,7 +372,7 @@ interface IORMTable {
 	 *
 	 * @see LoadBalancer::reuseConnection
 	 *
-	 * @param DatabaseBase $db the database
+	 * @param DatabaseBase $db The database
 	 *
 	 * @since 1.20
 	 */
@@ -386,7 +388,7 @@ interface IORMTable {
 	 * @param array $values
 	 * @param array $conditions
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function update( array $values, array $conditions = array() );
 
@@ -419,7 +421,7 @@ interface IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @param array|string $fields
+	 * @param array $fields
 	 *
 	 * @return array
 	 */
@@ -488,7 +490,7 @@ interface IORMTable {
 	 * @since 1.20
 	 *
 	 * @param array $data
-	 * @param boolean $loadDefaults
+	 * @param bool $loadDefaults
 	 *
 	 * @return IORMRow
 	 */
@@ -510,8 +512,7 @@ interface IORMTable {
 	 *
 	 * @param string $name
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function canHaveField( $name );
-
 }
diff --git a/includes/db/LBFactory.php b/includes/db/LBFactory.php
index 16c43a00..73456e23 100644
--- a/includes/db/LBFactory.php
+++ b/includes/db/LBFactory.php
@@ -26,11 +26,8 @@
  * @ingroup Database
  */
 abstract class LBFactory {
-
-	/**
-	 * @var LBFactory
-	 */
-	static $instance;
+	/** @var LBFactory */
+	protected static $instance;
 
 	/**
 	 * Disables all access to the load balancer, will cause all database access
@@ -38,7 +35,7 @@ abstract class LBFactory {
 	 */
 	public static function disableBackend() {
 		global $wgLBFactoryConf;
-		self::$instance = new LBFactory_Fake( $wgLBFactoryConf );
+		self::$instance = new LBFactoryFake( $wgLBFactoryConf );
 	}
 
 	/**
@@ -47,15 +44,47 @@ abstract class LBFactory {
 	 * @return LBFactory
 	 */
 	static function &singleton() {
+		global $wgLBFactoryConf;
+
 		if ( is_null( self::$instance ) ) {
-			global $wgLBFactoryConf;
-			$class = $wgLBFactoryConf['class'];
+			$class = self::getLBFactoryClass( $wgLBFactoryConf );
+
 			self::$instance = new $class( $wgLBFactoryConf );
 		}
+
 		return self::$instance;
 	}
 
 	/**
+	 * Returns the LBFactory class to use and the load balancer configuration.
+	 *
+	 * @param array $config (e.g. $wgLBFactoryConf)
+	 * @return string Class name
+	 */
+	public static function getLBFactoryClass( array $config ) {
+		// For configuration backward compatibility after removing
+		// underscores from class names in MediaWiki 1.23.
+		$bcClasses = array(
+			'LBFactory_Simple' => 'LBFactorySimple',
+			'LBFactory_Single' => 'LBFactorySingle',
+			'LBFactory_Multi' => 'LBFactoryMulti',
+			'LBFactory_Fake' => 'LBFactoryFake',
+		);
+
+		$class = $config['class'];
+
+		if ( isset( $bcClasses[$class] ) ) {
+			$class = $bcClasses[$class];
+			wfDeprecated(
+				'$wgLBFactoryConf must be updated. See RELEASE-NOTES for details',
+				'1.23'
+			);
+		}
+
+		return $class;
+	}
+
+	/**
 	 * Shut down, close connections and destroy the cached instance.
 	 */
 	static function destroyInstance() {
@@ -69,7 +98,7 @@ abstract class LBFactory {
 	/**
 	 * Set the instance to be the given object
 	 *
-	 * @param $instance LBFactory
+	 * @param LBFactory $instance
 	 */
 	static function setInstance( $instance ) {
 		self::destroyInstance();
@@ -78,7 +107,7 @@ abstract class LBFactory {
 
 	/**
 	 * Construct a factory based on a configuration array (typically from $wgLBFactoryConf)
-	 * @param $conf
+	 * @param array $conf
 	 */
 	abstract function __construct( $conf );
 
@@ -86,7 +115,7 @@ abstract class LBFactory {
 	 * Create a new load balancer object. The resulting object will be untracked,
 	 * not chronology-protected, and the caller is responsible for cleaning it up.
 	 *
-	 * @param string $wiki wiki ID, or false for the current wiki
+	 * @param bool|string $wiki Wiki ID, or false for the current wiki
 	 * @return LoadBalancer
 	 */
 	abstract function newMainLB( $wiki = false );
@@ -94,7 +123,7 @@ abstract class LBFactory {
 	/**
 	 * Get a cached (tracked) load balancer object.
 	 *
-	 * @param string $wiki wiki ID, or false for the current wiki
+	 * @param bool|string $wiki Wiki ID, or false for the current wiki
 	 * @return LoadBalancer
 	 */
 	abstract function getMainLB( $wiki = false );
@@ -104,9 +133,8 @@ abstract class LBFactory {
 	 * untracked, not chronology-protected, and the caller is responsible for
 	 * cleaning it up.
 	 *
-	 * @param string $cluster external storage cluster, or false for core
-	 * @param string $wiki wiki ID, or false for the current wiki
-	 *
+	 * @param string $cluster External storage cluster, or false for core
+	 * @param bool|string $wiki Wiki ID, or false for the current wiki
 	 * @return LoadBalancer
 	 */
 	abstract function newExternalLB( $cluster, $wiki = false );
@@ -114,9 +142,8 @@ abstract class LBFactory {
 	/**
 	 * Get a cached (tracked) load balancer for external storage
 	 *
-	 * @param string $cluster external storage cluster, or false for core
-	 * @param string $wiki wiki ID, or false for the current wiki
-	 *
+	 * @param string $cluster External storage cluster, or false for core
+	 * @param bool|string $wiki Wiki ID, or false for the current wiki
 	 * @return LoadBalancer
 	 */
 	abstract function &getExternalLB( $cluster, $wiki = false );
@@ -125,7 +152,8 @@ abstract class LBFactory {
 	 * Execute a function for each tracked load balancer
 	 * The callback is called with the load balancer as the first parameter,
 	 * and $params passed as the subsequent parameters.
-	 * @param $callback string|array
+	 *
+	 * @param callable $callback
 	 * @param array $params
 	 */
 	abstract function forEachLB( $callback, $params = array() );
@@ -139,8 +167,9 @@ abstract class LBFactory {
 
 	/**
 	 * Call a method of each tracked load balancer
-	 * @param $methodName string
-	 * @param $args array
+	 *
+	 * @param string $methodName
+	 * @param array $args
 	 */
 	function forEachLBCallMethod( $methodName, $args = array() ) {
 		$this->forEachLB( array( $this, 'callMethod' ), array( $methodName, $args ) );
@@ -148,9 +177,9 @@ abstract class LBFactory {
 
 	/**
 	 * Private helper for forEachLBCallMethod
-	 * @param $loadBalancer
-	 * @param $methodName string
-	 * @param $args
+	 * @param LoadBalancer $loadBalancer
+	 * @param string $methodName
+	 * @param array $args
 	 */
 	function callMethod( $loadBalancer, $methodName, $args ) {
 		call_user_func_array( array( $loadBalancer, $methodName ), $args );
@@ -162,39 +191,62 @@ abstract class LBFactory {
 	function commitMasterChanges() {
 		$this->forEachLBCallMethod( 'commitMasterChanges' );
 	}
+
+	/**
+	 * Rollback changes on all master connections
+	 * @since 1.23
+	 */
+	function rollbackMasterChanges() {
+		$this->forEachLBCallMethod( 'rollbackMasterChanges' );
+	}
+
+	/**
+	 * Detemine if any master connection has pending changes.
+	 * @since 1.23
+	 * @return bool
+	 */
+	function hasMasterChanges() {
+		$ret = false;
+		$this->forEachLB( function ( $lb ) use ( &$ret ) {
+			$ret = $ret || $lb->hasMasterChanges();
+		} );
+		return $ret;
+	}
 }
 
 /**
  * A simple single-master LBFactory that gets its configuration from the b/c globals
  */
-class LBFactory_Simple extends LBFactory {
+class LBFactorySimple extends LBFactory {
+	/** @var LoadBalancer */
+	protected $mainLB;
 
-	/**
-	 * @var LoadBalancer
-	 */
-	var $mainLB;
-	var $extLBs = array();
+	/** @var LoadBalancer[] */
+	protected $extLBs = array();
 
-	# Chronology protector
-	var $chronProt;
+	/** @var ChronologyProtector */
+	protected $chronProt;
 
 	function __construct( $conf ) {
 		$this->chronProt = new ChronologyProtector;
 	}
 
 	/**
-	 * @param $wiki
+	 * @param bool|string $wiki
 	 * @return LoadBalancer
 	 */
 	function newMainLB( $wiki = false ) {
-		global $wgDBservers, $wgMasterWaitTimeout;
+		global $wgDBservers;
 		if ( $wgDBservers ) {
 			$servers = $wgDBservers;
 		} else {
 			global $wgDBserver, $wgDBuser, $wgDBpassword, $wgDBname, $wgDBtype, $wgDebugDumpSql;
 			global $wgDBssl, $wgDBcompress;
 
-			$flags = ( $wgDebugDumpSql ? DBO_DEBUG : 0 ) | DBO_DEFAULT;
+			$flags = DBO_DEFAULT;
+			if ( $wgDebugDumpSql ) {
+				$flags |= DBO_DEBUG;
+			}
 			if ( $wgDBssl ) {
 				$flags |= DBO_SSL;
 			}
@@ -210,17 +262,16 @@ class LBFactory_Simple extends LBFactory {
 				'type' => $wgDBtype,
 				'load' => 1,
 				'flags' => $flags
-			));
+			) );
 		}
 
 		return new LoadBalancer( array(
 			'servers' => $servers,
-			'masterWaitTimeout' => $wgMasterWaitTimeout
-		));
+		) );
 	}
 
 	/**
-	 * @param $wiki
+	 * @param bool|string $wiki
 	 * @return LoadBalancer
 	 */
 	function getMainLB( $wiki = false ) {
@@ -229,13 +280,14 @@ class LBFactory_Simple extends LBFactory {
 			$this->mainLB->parentInfo( array( 'id' => 'main' ) );
 			$this->chronProt->initLB( $this->mainLB );
 		}
+
 		return $this->mainLB;
 	}
 
 	/**
 	 * @throws MWException
-	 * @param $cluster
-	 * @param $wiki
+	 * @param string $cluster
+	 * @param bool|string $wiki
 	 * @return LoadBalancer
 	 */
 	function newExternalLB( $cluster, $wiki = false ) {
@@ -243,14 +295,15 @@ class LBFactory_Simple extends LBFactory {
 		if ( !isset( $wgExternalServers[$cluster] ) ) {
 			throw new MWException( __METHOD__ . ": Unknown cluster \"$cluster\"" );
 		}
+
 		return new LoadBalancer( array(
 			'servers' => $wgExternalServers[$cluster]
-		));
+		) );
 	}
 
 	/**
-	 * @param $cluster
-	 * @param $wiki
+	 * @param string $cluster
+	 * @param bool|string $wiki
 	 * @return array
 	 */
 	function &getExternalLB( $cluster, $wiki = false ) {
@@ -259,6 +312,7 @@ class LBFactory_Simple extends LBFactory {
 			$this->extLBs[$cluster]->parentInfo( array( 'id' => "ext-$cluster" ) );
 			$this->chronProt->initLB( $this->extLBs[$cluster] );
 		}
+
 		return $this->extLBs[$cluster];
 	}
 
@@ -266,8 +320,9 @@ class LBFactory_Simple extends LBFactory {
 	 * Execute a function for each tracked load balancer
 	 * The callback is called with the load balancer as the first parameter,
 	 * and $params passed as the subsequent parameters.
-	 * @param $callback
-	 * @param $params array
+	 *
+	 * @param callable $callback
+	 * @param array $params
 	 */
 	function forEachLB( $callback, $params = array() ) {
 		if ( isset( $this->mainLB ) ) {
@@ -296,7 +351,7 @@ class LBFactory_Simple extends LBFactory {
  * Call LBFactory::disableBackend() to start using this, and
  * LBFactory::enableBackend() to return to normal behavior
  */
-class LBFactory_Fake extends LBFactory {
+class LBFactoryFake extends LBFactory {
 	function __construct( $conf ) {
 	}
 
@@ -325,6 +380,7 @@ class LBFactory_Fake extends LBFactory {
  */
 class DBAccessError extends MWException {
 	function __construct() {
-		parent::__construct( "Mediawiki tried to access the database via wfGetDB(). This is not allowed." );
+		parent::__construct( "Mediawiki tried to access the database via wfGetDB(). " .
+			"This is not allowed." );
 	}
 }
diff --git a/includes/db/LBFactory_Multi.php b/includes/db/LBFactoryMulti.php
index 3043946a..bac96523 100644
--- a/includes/db/LBFactory_Multi.php
+++ b/includes/db/LBFactoryMulti.php
@@ -26,49 +26,130 @@
  * Ignores the old configuration globals
  *
  * Configuration:
- *     sectionsByDB                A map of database names to section names
+ *     sectionsByDB                A map of database names to section names.
  *
- *     sectionLoads                A 2-d map. For each section, gives a map of server names to load ratios.
- *                                 For example: array( 'section1' => array( 'db1' => 100, 'db2' => 100 ) )
+ *     sectionLoads                A 2-d map. For each section, gives a map of server names to
+ *                                 load ratios. For example:
+ *                                 array(
+ *                                     'section1' => array(
+ *                                         'db1' => 100,
+ *                                         'db2' => 100
+ *                                     )
+ *                                 )
  *
- *     serverTemplate              A server info associative array as documented for $wgDBservers. The host,
- *                                 hostName and load entries will be overridden.
+ *     serverTemplate              A server info associative array as documented for $wgDBservers.
+ *                                 The host, hostName and load entries will be overridden.
  *
- *     groupLoadsBySection         A 3-d map giving server load ratios for each section and group. For example:
- *                                 array( 'section1' => array( 'group1' => array( 'db1' => 100, 'db2' => 100 ) ) )
+ *     groupLoadsBySection         A 3-d map giving server load ratios for each section and group.
+ *                                 For example:
+ *                                 array(
+ *                                     'section1' => array(
+ *                                         'group1' => array(
+ *                                             'db1' => 100,
+ *                                             'db2' => 100
+ *                                         )
+ *                                     )
+ *                                 )
  *
  *     groupLoadsByDB              A 3-d map giving server load ratios by DB name.
  *
  *     hostsByName                 A map of hostname to IP address.
  *
- *     externalLoads               A map of external storage cluster name to server load map
+ *     externalLoads               A map of external storage cluster name to server load map.
  *
- *     externalTemplateOverrides   A set of server info keys overriding serverTemplate for external storage
+ *     externalTemplateOverrides   A set of server info keys overriding serverTemplate for external
+ *                                 storage.
  *
- *     templateOverridesByServer   A 2-d map overriding serverTemplate and externalTemplateOverrides on a
- *                                 server-by-server basis. Applies to both core and external storage.
+ *     templateOverridesByServer   A 2-d map overriding serverTemplate and
+ *                                 externalTemplateOverrides on a server-by-server basis. Applies
+ *                                 to both core and external storage.
  *
- *     templateOverridesByCluster  A 2-d map overriding the server info by external storage cluster
+ *     templateOverridesByCluster  A 2-d map overriding the server info by external storage cluster.
  *
  *     masterTemplateOverrides     An override array for all master servers.
  *
- *     readOnlyBySection           A map of section name to read-only message. Missing or false for read/write.
+ *     readOnlyBySection           A map of section name to read-only message.
+ *                                 Missing or false for read/write.
  *
  * @ingroup Database
  */
-class LBFactory_Multi extends LBFactory {
+class LBFactoryMulti extends LBFactory {
 	// Required settings
-	var $sectionsByDB, $sectionLoads, $serverTemplate;
+
+	/** @var array A map of database names to section names */
+	protected $sectionsByDB;
+
+	/**
+	 * @var array A 2-d map. For each section, gives a map of server names to
+	 * load ratios
+	 */
+	protected $sectionLoads;
+
+	/**
+	 * @var array A server info associative array as documented for
+	 * $wgDBservers. The host, hostName and load entries will be
+	 * overridden
+	 */
+	protected $serverTemplate;
+
 	// Optional settings
-	var $groupLoadsBySection = array(), $groupLoadsByDB = array(), $hostsByName = array();
-	var $externalLoads = array(), $externalTemplateOverrides, $templateOverridesByServer;
-	var $templateOverridesByCluster, $masterTemplateOverrides, $readOnlyBySection = array();
+
+	/** @var array A 3-d map giving server load ratios for each section and group */
+	protected $groupLoadsBySection = array();
+
+	/** @var array A 3-d map giving server load ratios by DB name */
+	protected $groupLoadsByDB = array();
+
+	/** @var array A map of hostname to IP address */
+	protected $hostsByName = array();
+
+	/** @var array A map of external storage cluster name to server load map */
+	protected $externalLoads = array();
+
+	/**
+	 * @var array A set of server info keys overriding serverTemplate for
+	 * external storage
+	 */
+	protected $externalTemplateOverrides;
+
+	/**
+	 * @var array A 2-d map overriding serverTemplate and
+	 * externalTemplateOverrides on a server-by-server basis. Applies to both
+	 * core and external storage
+	 */
+	protected $templateOverridesByServer;
+
+	/** @var array A 2-d map overriding the server info by external storage cluster */
+	protected $templateOverridesByCluster;
+
+	/** @var array An override array for all master servers */
+	protected $masterTemplateOverrides;
+
+	/**
+	 * @var array|bool A map of section name to read-only message. Missing or
+	 * false for read/write
+	 */
+	protected $readOnlyBySection = array();
+
 	// Other stuff
-	var $conf, $mainLBs = array(), $extLBs = array();
-	var $lastWiki, $lastSection;
+
+	/** @var array Load balancer factory configuration */
+	protected $conf;
+
+	/** @var LoadBalancer[] */
+	protected $mainLBs = array();
+
+	/** @var LoadBalancer[] */
+	protected $extLBs = array();
+
+	/** @var string */
+	protected $lastWiki;
+
+	/** @var string */
+	protected $lastSection;
 
 	/**
-	 * @param $conf array
+	 * @param array $conf
 	 * @throws MWException
 	 */
 	function __construct( $conf ) {
@@ -102,7 +183,7 @@ class LBFactory_Multi extends LBFactory {
 	}
 
 	/**
-	 * @param $wiki bool|string
+	 * @param bool|string $wiki
 	 * @return string
 	 */
 	function getSectionForWiki( $wiki = false ) {
@@ -117,11 +198,12 @@ class LBFactory_Multi extends LBFactory {
 		}
 		$this->lastSection = $section;
 		$this->lastWiki = $wiki;
+
 		return $section;
 	}
 
 	/**
-	 * @param $wiki bool|string
+	 * @param bool|string $wiki
 	 * @return LoadBalancer
 	 */
 	function newMainLB( $wiki = false ) {
@@ -131,14 +213,20 @@ class LBFactory_Multi extends LBFactory {
 		if ( isset( $this->groupLoadsByDB[$dbName] ) ) {
 			$groupLoads = $this->groupLoadsByDB[$dbName];
 		}
+
 		if ( isset( $this->groupLoadsBySection[$section] ) ) {
 			$groupLoads = array_merge_recursive( $groupLoads, $this->groupLoadsBySection[$section] );
 		}
-		return $this->newLoadBalancer( $this->serverTemplate, $this->sectionLoads[$section], $groupLoads );
+
+		return $this->newLoadBalancer(
+			$this->serverTemplate,
+			$this->sectionLoads[$section],
+			$groupLoads
+		);
 	}
 
 	/**
-	 * @param $wiki bool|string
+	 * @param bool|string $wiki
 	 * @return LoadBalancer
 	 */
 	function getMainLB( $wiki = false ) {
@@ -149,12 +237,13 @@ class LBFactory_Multi extends LBFactory {
 			$this->chronProt->initLB( $lb );
 			$this->mainLBs[$section] = $lb;
 		}
+
 		return $this->mainLBs[$section];
 	}
 
 	/**
 	 * @param string $cluster
-	 * @param bool $wiki
+	 * @param bool|string $wiki
 	 * @throws MWException
 	 * @return LoadBalancer
 	 */
@@ -169,12 +258,13 @@ class LBFactory_Multi extends LBFactory {
 		if ( isset( $this->templateOverridesByCluster[$cluster] ) ) {
 			$template = $this->templateOverridesByCluster[$cluster] + $template;
 		}
+
 		return $this->newLoadBalancer( $template, $this->externalLoads[$cluster], array() );
 	}
 
 	/**
-	 * @param $cluster
-	 * @param $wiki
+	 * @param string $cluster External storage cluster, or false for core
+	 * @param bool|string $wiki Wiki ID, or false for the current wiki
 	 * @return LoadBalancer
 	 */
 	function &getExternalLB( $cluster, $wiki = false ) {
@@ -183,33 +273,33 @@ class LBFactory_Multi extends LBFactory {
 			$this->extLBs[$cluster]->parentInfo( array( 'id' => "ext-$cluster" ) );
 			$this->chronProt->initLB( $this->extLBs[$cluster] );
 		}
+
 		return $this->extLBs[$cluster];
 	}
 
 	/**
 	 * Make a new load balancer object based on template and load array
 	 *
-	 * @param $template
-	 * @param $loads array
-	 * @param $groupLoads
+	 * @param array $template
+	 * @param array $loads
+	 * @param array $groupLoads
 	 * @return LoadBalancer
 	 */
 	function newLoadBalancer( $template, $loads, $groupLoads ) {
-		global $wgMasterWaitTimeout;
 		$servers = $this->makeServerArray( $template, $loads, $groupLoads );
 		$lb = new LoadBalancer( array(
 			'servers' => $servers,
-			'masterWaitTimeout' => $wgMasterWaitTimeout
-		));
+		) );
+
 		return $lb;
 	}
 
 	/**
 	 * Make a server array as expected by LoadBalancer::__construct, using a template and load array
 	 *
-	 * @param $template
-	 * @param $loads array
-	 * @param $groupLoads
+	 * @param array $template
+	 * @param array $loads
+	 * @param array $groupLoads
 	 * @return array
 	 */
 	function makeServerArray( $template, $loads, $groupLoads ) {
@@ -245,12 +335,13 @@ class LBFactory_Multi extends LBFactory {
 			$serverInfo['load'] = $load;
 			$servers[] = $serverInfo;
 		}
+
 		return $servers;
 	}
 
 	/**
 	 * Take a group load array indexed by group then server, and reindex it by server then group
-	 * @param $groupLoads
+	 * @param array $groupLoads
 	 * @return array
 	 */
 	function reindexGroupLoads( $groupLoads ) {
@@ -260,17 +351,19 @@ class LBFactory_Multi extends LBFactory {
 				$reindexed[$server][$group] = $load;
 			}
 		}
+
 		return $reindexed;
 	}
 
 	/**
 	 * Get the database name and prefix based on the wiki ID
-	 * @param $wiki bool
+	 * @param bool|string $wiki
 	 * @return array
 	 */
 	function getDBNameAndPrefix( $wiki = false ) {
 		if ( $wiki === false ) {
 			global $wgDBname, $wgDBprefix;
+
 			return array( $wgDBname, $wgDBprefix );
 		} else {
 			return wfSplitWikiID( $wiki );
@@ -281,8 +374,8 @@ class LBFactory_Multi extends LBFactory {
 	 * Execute a function for each tracked load balancer
 	 * The callback is called with the load balancer as the first parameter,
 	 * and $params passed as the subsequent parameters.
-	 * @param $callback
-	 * @param $params array
+	 * @param callable $callback
+	 * @param array $params
 	 */
 	function forEachLB( $callback, $params = array() ) {
 		foreach ( $this->mainLBs as $lb ) {
diff --git a/includes/db/LBFactory_Single.php b/includes/db/LBFactorySingle.php
index 7dca06d7..3a4d829b 100644
--- a/includes/db/LBFactory_Single.php
+++ b/includes/db/LBFactorySingle.php
@@ -24,7 +24,8 @@
 /**
  * An LBFactory class that always returns a single database object.
  */
-class LBFactory_Single extends LBFactory {
+class LBFactorySingle extends LBFactory {
+	/** @var LoadBalancerSingle */
 	protected $lb;
 
 	/**
@@ -32,50 +33,46 @@ class LBFactory_Single extends LBFactory {
 	 *  - connection: The DatabaseBase connection object
 	 */
 	function __construct( $conf ) {
-		$this->lb = new LoadBalancer_Single( $conf );
+		$this->lb = new LoadBalancerSingle( $conf );
 	}
 
 	/**
-	 * @param $wiki bool|string
-	 *
-	 * @return LoadBalancer_Single
+	 * @param bool|string $wiki
+	 * @return LoadBalancerSingle
 	 */
 	function newMainLB( $wiki = false ) {
 		return $this->lb;
 	}
 
 	/**
-	 * @param $wiki bool|string
-	 *
-	 * @return LoadBalancer_Single
+	 * @param bool|string $wiki
+	 * @return LoadBalancerSingle
 	 */
 	function getMainLB( $wiki = false ) {
 		return $this->lb;
 	}
 
 	/**
-	 * @param $cluster
-	 * @param $wiki bool|string
-	 *
-	 * @return LoadBalancer_Single
+	 * @param string $cluster External storage cluster, or false for core
+	 * @param bool|string $wiki Wiki ID, or false for the current wiki
+	 * @return LoadBalancerSingle
 	 */
 	function newExternalLB( $cluster, $wiki = false ) {
 		return $this->lb;
 	}
 
 	/**
-	 * @param $cluster
-	 * @param $wiki bool|string
-	 *
-	 * @return LoadBalancer_Single
+	 * @param string $cluster External storage cluster, or false for core
+	 * @param bool|string $wiki Wiki ID, or false for the current wiki
+	 * @return LoadBalancerSingle
 	 */
 	function &getExternalLB( $cluster, $wiki = false ) {
 		return $this->lb;
 	}
 
 	/**
-	 * @param $callback string|array
-	 * @param $params array
+	 * @param string|callable $callback
+	 * @param array $params
 	 */
 	function forEachLB( $callback, $params = array() ) {
 		call_user_func_array( $callback, array_merge( array( $this->lb ), $params ) );
@@ -83,17 +80,14 @@ class LBFactory_Single extends LBFactory {
 }
 
 /**
- * Helper class for LBFactory_Single.
+ * Helper class for LBFactorySingle.
  */
-class LoadBalancer_Single extends LoadBalancer {
-
-	/**
-	 * @var DatabaseBase
-	 */
-	var $db;
+class LoadBalancerSingle extends LoadBalancer {
+	/** @var DatabaseBase */
+	protected $db;
 
 	/**
-	 * @param $params array
+	 * @param array $params
 	 */
 	function __construct( $params ) {
 		$this->db = $params['connection'];
@@ -107,8 +101,8 @@ class LoadBalancer_Single extends LoadBalancer {
 
 	/**
 	 *
-	 * @param $server string
-	 * @param $dbNameOverride bool
+	 * @param string $server
+	 * @param bool $dbNameOverride
 	 *
 	 * @return DatabaseBase
 	 */
diff --git a/includes/db/LoadBalancer.php b/includes/db/LoadBalancer.php
index 857109db..e517a025 100644
--- a/includes/db/LoadBalancer.php
+++ b/includes/db/LoadBalancer.php
@@ -28,19 +28,43 @@
  * @ingroup Database
  */
 class LoadBalancer {
-	private $mServers, $mConns, $mLoads, $mGroupLoads;
+	/** @var array Map of (server index => server config array) */
+	private $mServers;
+	/** @var array Map of (local/foreignUsed/foreignFree => server index => DatabaseBase array) */
+	private $mConns;
+	/** @var array Map of (server index => weight) */
+	private $mLoads;
+	/** @var array Map of (group => server index => weight) */
+	private $mGroupLoads;
+	/** @var bool Whether to disregard slave lag as a factor in slave selection */
+	private $mAllowLagged;
+	/** @var integer Seconds to spend waiting on slave lag to resolve */
+	private $mWaitTimeout;
+
+	/** @var array LBFactory information */
+	private $mParentInfo;
+	/** @var string The LoadMonitor subclass name */
+	private $mLoadMonitorClass;
+	/** @var LoadMonitor */
+	private $mLoadMonitor;
+
+	/** @var bool|DatabaseBase Database connection that caused a problem */
 	private $mErrorConnection;
-	private $mReadIndex, $mAllowLagged;
-	private $mWaitForPos, $mWaitTimeout;
-	private $mLaggedSlaveMode, $mLastError = 'Unknown error';
-	private $mParentInfo, $mLagTimes;
-	private $mLoadMonitorClass, $mLoadMonitor;
+	/** @var integer The generic (not query grouped) slave index (of $mServers) */
+	private $mReadIndex;
+	/** @var bool|DBMasterPos False if not set */
+	private $mWaitForPos;
+	/** @var bool Whether the generic reader fell back to a lagged slave */
+	private $mLaggedSlaveMode;
+	/** @var string The last DB selection or connection error */
+	private $mLastError = 'Unknown error';
+	/** @var array Process cache of LoadMonitor::getLagTimes() */
+	private $mLagTimes;
 
 	/**
-	 * @param array $params with keys:
-	 *    servers           Required. Array of server info structures.
-	 *    masterWaitTimeout Replication lag wait timeout
-	 *    loadMonitor       Name of a class used to fetch server lag and load.
+	 * @param array $params Array with keys:
+	 *   servers           Required. Array of server info structures.
+	 *   loadMonitor       Name of a class used to fetch server lag and load.
 	 * @throws MWException
 	 */
 	function __construct( $params ) {
@@ -48,12 +72,7 @@ class LoadBalancer {
 			throw new MWException( __CLASS__ . ': missing servers parameter' );
 		}
 		$this->mServers = $params['servers'];
-
-		if ( isset( $params['waitTimeout'] ) ) {
-			$this->mWaitTimeout = $params['waitTimeout'];
-		} else {
-			$this->mWaitTimeout = 10;
-		}
+		$this->mWaitTimeout = 10;
 
 		$this->mReadIndex = -1;
 		$this->mWriteIndex = -1;
@@ -72,9 +91,9 @@ class LoadBalancer {
 		} else {
 			$master = reset( $params['servers'] );
 			if ( isset( $master['type'] ) && $master['type'] === 'mysql' ) {
-				$this->mLoadMonitorClass = 'LoadMonitor_MySQL';
+				$this->mLoadMonitorClass = 'LoadMonitorMySQL';
 			} else {
-				$this->mLoadMonitorClass = 'LoadMonitor_Null';
+				$this->mLoadMonitorClass = 'LoadMonitorNull';
 			}
 		}
 
@@ -101,13 +120,14 @@ class LoadBalancer {
 			$class = $this->mLoadMonitorClass;
 			$this->mLoadMonitor = new $class( $this );
 		}
+
 		return $this->mLoadMonitor;
 	}
 
 	/**
 	 * Get or set arbitrary data used by the parent object, usually an LBFactory
-	 * @param $x
-	 * @return Mixed
+	 * @param mixed $x
+	 * @return mixed
 	 */
 	function parentInfo( $x = null ) {
 		return wfSetVar( $this->mParentInfo, $x );
@@ -119,8 +139,7 @@ class LoadBalancer {
 	 *
 	 * @deprecated since 1.21, use ArrayUtils::pickRandom()
 	 *
-	 * @param $weights array
-	 *
+	 * @param array $weights
 	 * @return bool|int|string
 	 */
 	function pickRandom( $weights ) {
@@ -128,8 +147,8 @@ class LoadBalancer {
 	}
 
 	/**
-	 * @param $loads array
-	 * @param $wiki bool
+	 * @param array $loads
+	 * @param bool|string $wiki Wiki to get non-lagged for
 	 * @return bool|int|string
 	 */
 	function getRandomNonLagged( $loads, $wiki = false ) {
@@ -138,10 +157,10 @@ class LoadBalancer {
 		foreach ( $lags as $i => $lag ) {
 			if ( $i != 0 ) {
 				if ( $lag === false ) {
-					wfDebugLog( 'replication', "Server #$i is not replicating\n" );
+					wfDebugLog( 'replication', "Server #$i is not replicating" );
 					unset( $loads[$i] );
 				} elseif ( isset( $this->mServers[$i]['max lag'] ) && $lag > $this->mServers[$i]['max lag'] ) {
-					wfDebugLog( 'replication', "Server #$i is excessively lagged ($lag seconds)\n" );
+					wfDebugLog( 'replication', "Server #$i is excessively lagged ($lag seconds)" );
 					unset( $loads[$i] );
 				}
 			}
@@ -176,13 +195,13 @@ class LoadBalancer {
 	 * always return a consistent index during a given invocation
 	 *
 	 * Side effect: opens connections to databases
-	 * @param $group bool
-	 * @param $wiki bool
+	 * @param bool|string $group
+	 * @param bool|string $wiki
 	 * @throws MWException
 	 * @return bool|int|string
 	 */
 	function getReaderIndex( $group = false, $wiki = false ) {
-		global $wgReadOnly, $wgDBClusterTimeout, $wgDBAvgStatusPoll, $wgDBtype;
+		global $wgReadOnly, $wgDBtype;
 
 		# @todo FIXME: For now, only go through all this for mysql databases
 		if ( $wgDBtype != 'mysql' ) {
@@ -192,17 +211,12 @@ class LoadBalancer {
 		if ( count( $this->mServers ) == 1 ) {
 			# Skip the load balancing if there's only one server
 			return 0;
-		} elseif ( $group === false and $this->mReadIndex >= 0 ) {
+		} elseif ( $group === false && $this->mReadIndex >= 0 ) {
 			# Shortcut if generic reader exists already
 			return $this->mReadIndex;
 		}
 
-		wfProfileIn( __METHOD__ );
-
-		$totalElapsed = 0;
-
-		# convert from seconds to microseconds
-		$timeout = $wgDBClusterTimeout * 1e6;
+		$section = new ProfileSection( __METHOD__ );
 
 		# Find the relevant load array
 		if ( $group !== false ) {
@@ -211,15 +225,14 @@ class LoadBalancer {
 			} else {
 				# No loads for this group, return false and the caller can use some other group
 				wfDebug( __METHOD__ . ": no loads for group $group\n" );
-				wfProfileOut( __METHOD__ );
+
 				return false;
 			}
 		} else {
 			$nonErrorLoads = $this->mLoads;
 		}
 
-		if ( !$nonErrorLoads ) {
-			wfProfileOut( __METHOD__ );
+		if ( !count( $nonErrorLoads ) ) {
 			throw new MWException( "Empty server array given to LoadBalancer" );
 		}
 
@@ -228,92 +241,60 @@ class LoadBalancer {
 
 		$laggedSlaveMode = false;
 
+		# No server found yet
+		$i = false;
 		# First try quickly looking through the available servers for a server that
 		# meets our criteria
-		do {
-			$totalThreadsConnected = 0;
-			$overloadedServers = 0;
-			$currentLoads = $nonErrorLoads;
-			while ( count( $currentLoads ) ) {
-				if ( $wgReadOnly || $this->mAllowLagged || $laggedSlaveMode ) {
+		$currentLoads = $nonErrorLoads;
+		while ( count( $currentLoads ) ) {
+			if ( $wgReadOnly || $this->mAllowLagged || $laggedSlaveMode ) {
+				$i = ArrayUtils::pickRandom( $currentLoads );
+			} else {
+				$i = $this->getRandomNonLagged( $currentLoads, $wiki );
+				if ( $i === false && count( $currentLoads ) != 0 ) {
+					# All slaves lagged. Switch to read-only mode
+					wfDebugLog( 'replication', "All slaves lagged. Switch to read-only mode" );
+					$wgReadOnly = 'The database has been automatically locked ' .
+						'while the slave database servers catch up to the master';
 					$i = ArrayUtils::pickRandom( $currentLoads );
-				} else {
-					$i = $this->getRandomNonLagged( $currentLoads, $wiki );
-					if ( $i === false && count( $currentLoads ) != 0 ) {
-						# All slaves lagged. Switch to read-only mode
-						wfDebugLog( 'replication', "All slaves lagged. Switch to read-only mode\n" );
-						$wgReadOnly = 'The database has been automatically locked ' .
-							'while the slave database servers catch up to the master';
-						$i = ArrayUtils::pickRandom( $currentLoads );
-						$laggedSlaveMode = true;
-					}
-				}
-
-				if ( $i === false ) {
-					# pickRandom() returned false
-					# This is permanent and means the configuration or the load monitor
-					# wants us to return false.
-					wfDebugLog( 'connect', __METHOD__ . ": pickRandom() returned false\n" );
-					wfProfileOut( __METHOD__ );
-					return false;
+					$laggedSlaveMode = true;
 				}
+			}
 
-				wfDebugLog( 'connect', __METHOD__ . ": Using reader #$i: {$this->mServers[$i]['host']}...\n" );
-				$conn = $this->openConnection( $i, $wiki );
-
-				if ( !$conn ) {
-					wfDebugLog( 'connect', __METHOD__ . ": Failed connecting to $i/$wiki\n" );
-					unset( $nonErrorLoads[$i] );
-					unset( $currentLoads[$i] );
-					continue;
-				}
-
-				// Perform post-connection backoff
-				$threshold = isset( $this->mServers[$i]['max threads'] )
-					? $this->mServers[$i]['max threads'] : false;
-				$backoff = $this->getLoadMonitor()->postConnectionBackoff( $conn, $threshold );
-
-				// Decrement reference counter, we are finished with this connection.
-				// It will be incremented for the caller later.
-				if ( $wiki !== false ) {
-					$this->reuseConnection( $conn );
-				}
+			if ( $i === false ) {
+				# pickRandom() returned false
+				# This is permanent and means the configuration or the load monitor
+				# wants us to return false.
+				wfDebugLog( 'connect', __METHOD__ . ": pickRandom() returned false" );
 
-				if ( $backoff ) {
-					# Post-connection overload, don't use this server for now
-					$totalThreadsConnected += $backoff;
-					$overloadedServers++;
-					unset( $currentLoads[$i] );
-				} else {
-					# Return this server
-					break 2;
-				}
+				return false;
 			}
 
-			# No server found yet
-			$i = false;
+			wfDebugLog( 'connect', __METHOD__ .
+				": Using reader #$i: {$this->mServers[$i]['host']}..." );
 
-			# If all servers were down, quit now
-			if ( !count( $nonErrorLoads ) ) {
-				wfDebugLog( 'connect', "All servers down\n" );
-				break;
+			$conn = $this->openConnection( $i, $wiki );
+			if ( !$conn ) {
+				wfDebugLog( 'connect', __METHOD__ . ": Failed connecting to $i/$wiki" );
+				unset( $nonErrorLoads[$i] );
+				unset( $currentLoads[$i] );
+				$i = false;
+				continue;
 			}
 
-			# Some servers must have been overloaded
-			if ( $overloadedServers == 0 ) {
-				throw new MWException( __METHOD__ . ": unexpectedly found no overloaded servers" );
+			// Decrement reference counter, we are finished with this connection.
+			// It will be incremented for the caller later.
+			if ( $wiki !== false ) {
+				$this->reuseConnection( $conn );
 			}
-			# Back off for a while
-			# Scale the sleep time by the number of connected threads, to produce a
-			# roughly constant global poll rate
-			$avgThreads = $totalThreadsConnected / $overloadedServers;
-			$totalElapsed += $this->sleep( $wgDBAvgStatusPoll * $avgThreads );
-		} while ( $totalElapsed < $timeout );
-
-		if ( $totalElapsed >= $timeout ) {
-			wfDebugLog( 'connect', "All servers busy\n" );
-			$this->mErrorConnection = false;
-			$this->mLastError = 'All servers busy';
+
+			# Return this server
+			break;
+		}
+
+		# If all servers were down, quit now
+		if ( !count( $nonErrorLoads ) ) {
+			wfDebugLog( 'connect', "All servers down" );
 		}
 
 		if ( $i !== false ) {
@@ -324,17 +305,17 @@ class LoadBalancer {
 					$this->mServers[$i]['slave pos'] = $conn->getSlavePos();
 				}
 			}
-			if ( $this->mReadIndex <= 0 && $this->mLoads[$i] > 0 && $i !== false ) {
+			if ( $this->mReadIndex <= 0 && $this->mLoads[$i] > 0 && $group !== false ) {
 				$this->mReadIndex = $i;
 			}
 		}
-		wfProfileOut( __METHOD__ );
+
 		return $i;
 	}
 
 	/**
 	 * Wait for a specified number of microseconds, and return the period waited
-	 * @param $t int
+	 * @param int $t
 	 * @return int
 	 */
 	function sleep( $t ) {
@@ -342,6 +323,7 @@ class LoadBalancer {
 		wfDebug( __METHOD__ . ": waiting $t us\n" );
 		usleep( $t );
 		wfProfileOut( __METHOD__ );
+
 		return $t;
 	}
 
@@ -349,7 +331,7 @@ class LoadBalancer {
 	 * Set the master wait position
 	 * If a DB_SLAVE connection has been opened already, waits
 	 * Otherwise sets a variable telling it to wait if such a connection is opened
-	 * @param $pos DBMasterPos
+	 * @param DBMasterPos $pos
 	 */
 	public function waitFor( $pos ) {
 		wfProfileIn( __METHOD__ );
@@ -367,22 +349,31 @@ class LoadBalancer {
 
 	/**
 	 * Set the master wait position and wait for ALL slaves to catch up to it
-	 * @param $pos DBMasterPos
+	 * @param DBMasterPos $pos
+	 * @param int $timeout Max seconds to wait; default is mWaitTimeout
+	 * @return bool Success (able to connect and no timeouts reached)
 	 */
-	public function waitForAll( $pos ) {
+	public function waitForAll( $pos, $timeout = null ) {
 		wfProfileIn( __METHOD__ );
 		$this->mWaitForPos = $pos;
-		for ( $i = 1; $i < count( $this->mServers ); $i++ ) {
-			$this->doWait( $i, true );
+		$serverCount = count( $this->mServers );
+
+		$ok = true;
+		for ( $i = 1; $i < $serverCount; $i++ ) {
+			if ( $this->mLoads[$i] > 0 ) {
+				$ok = $this->doWait( $i, true, $timeout ) && $ok;
+			}
 		}
 		wfProfileOut( __METHOD__ );
+
+		return $ok;
 	}
 
 	/**
 	 * Get any open connection to a given server index, local or foreign
 	 * Returns false if there is no connection open
 	 *
-	 * @param $i int
+	 * @param int $i
 	 * @return DatabaseBase|bool False on failure
 	 */
 	function getAnyOpenConnection( $i ) {
@@ -391,40 +382,47 @@ class LoadBalancer {
 				return reset( $conns[$i] );
 			}
 		}
+
 		return false;
 	}
 
 	/**
 	 * Wait for a given slave to catch up to the master pos stored in $this
-	 * @param $index
-	 * @param $open bool
+	 * @param int $index Server index
+	 * @param bool $open Check the server even if a new connection has to be made
+	 * @param int $timeout Max seconds to wait; default is mWaitTimeout
 	 * @return bool
 	 */
-	protected function doWait( $index, $open = false ) {
+	protected function doWait( $index, $open = false, $timeout = null ) {
 		# Find a connection to wait on
 		$conn = $this->getAnyOpenConnection( $index );
 		if ( !$conn ) {
 			if ( !$open ) {
 				wfDebug( __METHOD__ . ": no connection open\n" );
+
 				return false;
 			} else {
 				$conn = $this->openConnection( $index, '' );
 				if ( !$conn ) {
 					wfDebug( __METHOD__ . ": failed to open connection\n" );
+
 					return false;
 				}
 			}
 		}
 
 		wfDebug( __METHOD__ . ": Waiting for slave #$index to catch up...\n" );
-		$result = $conn->masterPosWait( $this->mWaitForPos, $this->mWaitTimeout );
+		$timeout = $timeout ?: $this->mWaitTimeout;
+		$result = $conn->masterPosWait( $this->mWaitForPos, $timeout );
 
 		if ( $result == -1 || is_null( $result ) ) {
 			# Timed out waiting for slave, use master instead
 			wfDebug( __METHOD__ . ": Timed out waiting for slave #$index pos {$this->mWaitForPos}\n" );
+
 			return false;
 		} else {
 			wfDebug( __METHOD__ . ": Done\n" );
+
 			return true;
 		}
 	}
@@ -433,8 +431,8 @@ class LoadBalancer {
 	 * Get a connection by index
 	 * This is the main entry point for this class.
 	 *
-	 * @param $i Integer: server index
-	 * @param array $groups query groups
+	 * @param int $i Server index
+	 * @param array $groups Query groups
 	 * @param bool|string $wiki Wiki ID
 	 *
 	 * @throws MWException
@@ -443,12 +441,10 @@ class LoadBalancer {
 	public function &getConnection( $i, $groups = array(), $wiki = false ) {
 		wfProfileIn( __METHOD__ );
 
-		if ( $i == DB_LAST ) {
+		if ( $i === null || $i === false ) {
 			wfProfileOut( __METHOD__ );
-			throw new MWException( 'Attempt to call ' . __METHOD__ . ' with deprecated server index DB_LAST' );
-		} elseif ( $i === null || $i === false ) {
-			wfProfileOut( __METHOD__ );
-			throw new MWException( 'Attempt to call ' . __METHOD__ . ' with invalid server index' );
+			throw new MWException( 'Attempt to call ' . __METHOD__ .
+				' with invalid server index' );
 		}
 
 		if ( $wiki === wfWikiID() ) {
@@ -485,6 +481,7 @@ class LoadBalancer {
 			if ( $i === false ) {
 				$this->mLastError = 'No working slave server: ' . $this->mLastError;
 				wfProfileOut( __METHOD__ );
+
 				return $this->reportConnectionError();
 			}
 		}
@@ -493,10 +490,12 @@ class LoadBalancer {
 		$conn = $this->openConnection( $i, $wiki );
 		if ( !$conn ) {
 			wfProfileOut( __METHOD__ );
+
 			return $this->reportConnectionError();
 		}
 
 		wfProfileOut( __METHOD__ );
+
 		return $conn;
 	}
 
@@ -511,15 +510,9 @@ class LoadBalancer {
 	public function reuseConnection( $conn ) {
 		$serverIndex = $conn->getLBInfo( 'serverIndex' );
 		$refCount = $conn->getLBInfo( 'foreignPoolRefCount' );
-		$dbName = $conn->getDBname();
-		$prefix = $conn->tablePrefix();
-		if ( strval( $prefix ) !== '' ) {
-			$wiki = "$dbName-$prefix";
-		} else {
-			$wiki = $dbName;
-		}
 		if ( $serverIndex === null || $refCount === null ) {
 			wfDebug( __METHOD__ . ": this connection was not opened as a foreign connection\n" );
+
 			/**
 			 * This can happen in code like:
 			 *   foreach ( $dbs as $db ) {
@@ -530,10 +523,20 @@ class LoadBalancer {
 			 * When a connection to the local DB is opened in this way, reuseConnection()
 			 * should be ignored
 			 */
+
 			return;
 		}
+
+		$dbName = $conn->getDBname();
+		$prefix = $conn->tablePrefix();
+		if ( strval( $prefix ) !== '' ) {
+			$wiki = "$dbName-$prefix";
+		} else {
+			$wiki = $dbName;
+		}
 		if ( $this->mConns['foreignUsed'][$serverIndex][$wiki] !== $conn ) {
-			throw new MWException( __METHOD__ . ": connection not found, has the connection been freed already?" );
+			throw new MWException( __METHOD__ . ": connection not found, has " .
+				"the connection been freed already?" );
 		}
 		$conn->setLBInfo( 'foreignPoolRefCount', --$refCount );
 		if ( $refCount <= 0 ) {
@@ -552,9 +555,9 @@ class LoadBalancer {
 	 *
 	 * @see LoadBalancer::getConnection() for parameter information
 	 *
-	 * @param integer $db
+	 * @param int $db
 	 * @param mixed $groups
-	 * @param string $wiki
+	 * @param bool|string $wiki
 	 * @return DBConnRef
 	 */
 	public function getConnectionRef( $db, $groups = array(), $wiki = false ) {
@@ -568,9 +571,9 @@ class LoadBalancer {
 	 *
 	 * @see LoadBalancer::getConnection() for parameter information
 	 *
-	 * @param integer $db
+	 * @param int $db
 	 * @param mixed $groups
-	 * @param string $wiki
+	 * @param bool|string $wiki
 	 * @return DBConnRef
 	 */
 	public function getLazyConnectionRef( $db, $groups = array(), $wiki = false ) {
@@ -585,8 +588,8 @@ class LoadBalancer {
 	 * On error, returns false, and the connection which caused the
 	 * error will be available via $this->mErrorConnection.
 	 *
-	 * @param $i Integer server index
-	 * @param string $wiki wiki ID to open
+	 * @param int $i Server index
+	 * @param bool|string $wiki Wiki ID to open
 	 * @return DatabaseBase
 	 *
 	 * @access private
@@ -596,6 +599,7 @@ class LoadBalancer {
 		if ( $wiki !== false ) {
 			$conn = $this->openForeignConnection( $i, $wiki );
 			wfProfileOut( __METHOD__ );
+
 			return $conn;
 		}
 		if ( isset( $this->mConns['local'][$i][0] ) ) {
@@ -614,6 +618,7 @@ class LoadBalancer {
 			}
 		}
 		wfProfileOut( __METHOD__ );
+
 		return $conn;
 	}
 
@@ -631,8 +636,8 @@ class LoadBalancer {
 	 * On error, returns false, and the connection which caused the
 	 * error will be available via $this->mErrorConnection.
 	 *
-	 * @param $i Integer: server index
-	 * @param string $wiki wiki ID to open
+	 * @param int $i Server index
+	 * @param string $wiki Wiki ID to open
 	 * @return DatabaseBase
 	 */
 	function openForeignConnection( $i, $wiki ) {
@@ -688,13 +693,14 @@ class LoadBalancer {
 			$conn->setLBInfo( 'foreignPoolRefCount', $refCount + 1 );
 		}
 		wfProfileOut( __METHOD__ );
+
 		return $conn;
 	}
 
 	/**
 	 * Test if the specified index represents an open connection
 	 *
-	 * @param $index Integer: server index
+	 * @param int $index Server index
 	 * @access private
 	 * @return bool
 	 */
@@ -702,6 +708,7 @@ class LoadBalancer {
 		if ( !is_integer( $index ) ) {
 			return false;
 		}
+
 		return (bool)$this->getAnyOpenConnection( $index );
 	}
 
@@ -710,8 +717,8 @@ class LoadBalancer {
 	 * Returns a Database object whether or not the connection was successful.
 	 * @access private
 	 *
-	 * @param $server
-	 * @param $dbNameOverride bool
+	 * @param array $server
+	 * @param bool $dbNameOverride
 	 * @throws MWException
 	 * @return DatabaseBase
 	 */
@@ -741,6 +748,7 @@ class LoadBalancer {
 		if ( isset( $server['fakeMaster'] ) ) {
 			$db->setFakeMaster( true );
 		}
+
 		return $db;
 	}
 
@@ -753,15 +761,16 @@ class LoadBalancer {
 
 		if ( !is_object( $conn ) ) {
 			// No last connection, probably due to all servers being too busy
-			wfLogDBError( "LB failure with no last connection. Connection error: {$this->mLastError}\n" );
+			wfLogDBError( "LB failure with no last connection. Connection error: {$this->mLastError}" );
 
 			// If all servers were busy, mLastError will contain something sensible
 			throw new DBConnectionError( null, $this->mLastError );
 		} else {
 			$server = $conn->getProperty( 'mServer' );
-			wfLogDBError( "Connection error: {$this->mLastError} ({$server})\n" );
+			wfLogDBError( "Connection error: {$this->mLastError} ({$server})" );
 			$conn->reportConnectionError( "{$this->mLastError} ({$server})" ); // throws DBConnectionError
 		}
+
 		return false; /* not reached */
 	}
 
@@ -775,7 +784,7 @@ class LoadBalancer {
 	/**
 	 * Returns true if the specified index is a valid server index
 	 *
-	 * @param $i
+	 * @param string $i
 	 * @return bool
 	 */
 	function haveIndex( $i ) {
@@ -785,7 +794,7 @@ class LoadBalancer {
 	/**
 	 * Returns true if the specified index is valid and has non-zero load
 	 *
-	 * @param $i
+	 * @param string $i
 	 * @return bool
 	 */
 	function isNonZeroLoad( $i ) {
@@ -804,7 +813,7 @@ class LoadBalancer {
 	/**
 	 * Get the host name or IP address of the server with the specified index
 	 * Prefer a readable name if available.
-	 * @param $i
+	 * @param string $i
 	 * @return string
 	 */
 	function getServerName( $i ) {
@@ -819,8 +828,8 @@ class LoadBalancer {
 
 	/**
 	 * Return the server info structure for a given index, or false if the index is invalid.
-	 * @param $i
-	 * @return bool
+	 * @param int $i
+	 * @return array|bool
 	 */
 	function getServerInfo( $i ) {
 		if ( isset( $this->mServers[$i] ) ) {
@@ -831,9 +840,10 @@ class LoadBalancer {
 	}
 
 	/**
-	 * Sets the server info structure for the given index. Entry at index $i is created if it doesn't exist
-	 * @param $i
-	 * @param $serverInfo
+	 * Sets the server info structure for the given index. Entry at index $i
+	 * is created if it doesn't exist
+	 * @param int $i
+	 * @param array $serverInfo
 	 */
 	function setServerInfo( $i, $serverInfo ) {
 		$this->mServers[$i] = $serverInfo;
@@ -848,17 +858,21 @@ class LoadBalancer {
 		# master (however unlikely that may be), then we can fetch the position from the slave.
 		$masterConn = $this->getAnyOpenConnection( 0 );
 		if ( !$masterConn ) {
-			for ( $i = 1; $i < count( $this->mServers ); $i++ ) {
+			$serverCount = count( $this->mServers );
+			for ( $i = 1; $i < $serverCount; $i++ ) {
 				$conn = $this->getAnyOpenConnection( $i );
 				if ( $conn ) {
 					wfDebug( "Master pos fetched from slave\n" );
+
 					return $conn->getSlavePos();
 				}
 			}
 		} else {
 			wfDebug( "Master pos fetched from master\n" );
+
 			return $masterConn->getMasterPos();
 		}
+
 		return false;
 	}
 
@@ -868,6 +882,7 @@ class LoadBalancer {
 	function closeAll() {
 		foreach ( $this->mConns as $conns2 ) {
 			foreach ( $conns2 as $conns3 ) {
+				/** @var DatabaseBase $conn */
 				foreach ( $conns3 as $conn ) {
 					$conn->close();
 				}
@@ -881,21 +896,10 @@ class LoadBalancer {
 	}
 
 	/**
-	 * Deprecated function, typo in function name
-	 *
-	 * @deprecated in 1.18
-	 * @param $conn
-	 */
-	function closeConnecton( $conn ) {
-		wfDeprecated( __METHOD__, '1.18' );
-		$this->closeConnection( $conn );
-	}
-
-	/**
 	 * Close a connection
 	 * Using this function makes sure the LoadBalancer knows the connection is closed.
 	 * If you use $conn->close() directly, the load balancer won't update its state.
-	 * @param $conn DatabaseBase
+	 * @param DatabaseBase $conn
 	 */
 	function closeConnection( $conn ) {
 		$done = false;
@@ -922,6 +926,7 @@ class LoadBalancer {
 	function commitAll() {
 		foreach ( $this->mConns as $conns2 ) {
 			foreach ( $conns2 as $conns3 ) {
+				/** @var DatabaseBase[] $conns3 */
 				foreach ( $conns3 as $conn ) {
 					if ( $conn->trxLevel() ) {
 						$conn->commit( __METHOD__, 'flush' );
@@ -941,6 +946,7 @@ class LoadBalancer {
 			if ( empty( $conns2[$masterIndex] ) ) {
 				continue;
 			}
+			/** @var DatabaseBase $conn */
 			foreach ( $conns2[$masterIndex] as $conn ) {
 				if ( $conn->trxLevel() && $conn->writesOrCallbacksPending() ) {
 					$conn->commit( __METHOD__, 'flush' );
@@ -950,8 +956,59 @@ class LoadBalancer {
 	}
 
 	/**
-	 * @param $value null
-	 * @return Mixed
+	 * Issue ROLLBACK only on master, only if queries were done on connection
+	 * @since 1.23
+	 */
+	function rollbackMasterChanges() {
+		// Always 0, but who knows.. :)
+		$masterIndex = $this->getWriterIndex();
+		foreach ( $this->mConns as $conns2 ) {
+			if ( empty( $conns2[$masterIndex] ) ) {
+				continue;
+			}
+			/** @var DatabaseBase $conn */
+			foreach ( $conns2[$masterIndex] as $conn ) {
+				if ( $conn->trxLevel() && $conn->writesOrCallbacksPending() ) {
+					$conn->rollback( __METHOD__, 'flush' );
+				}
+			}
+		}
+	}
+
+	/**
+	 * @return bool Whether a master connection is already open
+	 * @since 1.24
+	 */
+	function hasMasterConnection() {
+		return $this->isOpen( $this->getWriterIndex() );
+	}
+
+	/**
+	 * Determine if there are any pending changes that need to be rolled back
+	 * or committed.
+	 * @since 1.23
+	 * @return bool
+	 */
+	function hasMasterChanges() {
+		// Always 0, but who knows.. :)
+		$masterIndex = $this->getWriterIndex();
+		foreach ( $this->mConns as $conns2 ) {
+			if ( empty( $conns2[$masterIndex] ) ) {
+				continue;
+			}
+			/** @var DatabaseBase $conn */
+			foreach ( $conns2[$masterIndex] as $conn ) {
+				if ( $conn->trxLevel() && $conn->writesOrCallbacksPending() ) {
+					return true;
+				}
+			}
+		}
+		return false;
+	}
+
+	/**
+	 * @param mixed $value
+	 * @return mixed
 	 */
 	function waitTimeout( $value = null ) {
 		return wfSetVar( $this->mWaitTimeout, $value );
@@ -966,7 +1023,7 @@ class LoadBalancer {
 
 	/**
 	 * Disables/enables lag checks
-	 * @param $mode null
+	 * @param null|bool $mode
 	 * @return bool
 	 */
 	function allowLagged( $mode = null ) {
@@ -974,6 +1031,7 @@ class LoadBalancer {
 			return $this->mAllowLagged;
 		}
 		$this->mAllowLagged = $mode;
+
 		return $this->mAllowLagged;
 	}
 
@@ -984,6 +1042,7 @@ class LoadBalancer {
 		$success = true;
 		foreach ( $this->mConns as $conns2 ) {
 			foreach ( $conns2 as $conns3 ) {
+				/** @var DatabaseBase[] $conns3 */
 				foreach ( $conns3 as $conn ) {
 					if ( !$conn->ping() ) {
 						$success = false;
@@ -991,12 +1050,13 @@ class LoadBalancer {
 				}
 			}
 		}
+
 		return $success;
 	}
 
 	/**
 	 * Call a function with each open connection object
-	 * @param $callback
+	 * @param callable $callback
 	 * @param array $params
 	 */
 	function forEachOpenConnection( $callback, $params = array() ) {
@@ -1016,16 +1076,29 @@ class LoadBalancer {
 	 * May attempt to open connections to slaves on the default DB. If there is
 	 * no lag, the maximum lag will be reported as -1.
 	 *
-	 * @param string $wiki Wiki ID, or false for the default database
-	 *
+	 * @param bool|string $wiki Wiki ID, or false for the default database
 	 * @return array ( host, max lag, index of max lagged host )
 	 */
 	function getMaxLag( $wiki = false ) {
 		$maxLag = -1;
 		$host = '';
 		$maxIndex = 0;
-		if ( $this->getServerCount() > 1 ) { // no replication = no lag
+
+		if ( $this->getServerCount() <= 1 ) { // no replication = no lag
+			return array( $host, $maxLag, $maxIndex );
+		}
+
+		// Try to get the max lag info from the server cache
+		$key = 'loadbalancer:maxlag:cluster:' . $this->mServers[0]['host'];
+		$cache = ObjectCache::newAccelerator( array(), 'hash' );
+		$maxLagInfo = $cache->get( $key ); // (host, lag, index)
+
+		// Fallback to connecting to each slave and getting the lag
+		if ( !$maxLagInfo ) {
 			foreach ( $this->mServers as $i => $conn ) {
+				if ( $i == $this->getWriterIndex() ) {
+					continue; // nothing to check
+				}
 				$conn = false;
 				if ( $wiki === false ) {
 					$conn = $this->getAnyOpenConnection( $i );
@@ -1043,16 +1116,18 @@ class LoadBalancer {
 					$maxIndex = $i;
 				}
 			}
+			$maxLagInfo = array( $host, $maxLag, $maxIndex );
+			$cache->set( $key, $maxLagInfo, 5 );
 		}
-		return array( $host, $maxLag, $maxIndex );
+
+		return $maxLagInfo;
 	}
 
 	/**
 	 * Get lag time for each server
 	 * Results are cached for a short time in memcached, and indefinitely in the process cache
 	 *
-	 * @param $wiki
-	 *
+	 * @param string|bool $wiki
 	 * @return array
 	 */
 	function getLagTimes( $wiki = false ) {
@@ -1068,6 +1143,7 @@ class LoadBalancer {
 			$this->mLagTimes = $this->getLoadMonitor()->getLagTimes(
 				array_keys( $this->mServers ), $wiki );
 		}
+
 		return $this->mLagTimes;
 	}
 
@@ -1082,8 +1158,7 @@ class LoadBalancer {
 	 * function instead of Database::getLag() avoids a fatal error in this
 	 * case on many installations.
 	 *
-	 * @param $conn DatabaseBase
-	 *
+	 * @param DatabaseBase $conn
 	 * @return int
 	 */
 	function safeGetLag( $conn ) {
@@ -1112,14 +1187,16 @@ class LoadBalancer {
 class DBConnRef implements IDatabase {
 	/** @var LoadBalancer */
 	protected $lb;
+
 	/** @var DatabaseBase|null */
 	protected $conn;
-	/** @var Array|null */
+
+	/** @var array|null */
 	protected $params;
 
 	/**
-	 * @param $lb LoadBalancer
-	 * @param $conn DatabaseBase|array Connection or (server index, group, wiki ID) array
+	 * @param LoadBalancer $lb
+	 * @param DatabaseBase|array $conn Connection or (server index, group, wiki ID) array
 	 */
 	public function __construct( LoadBalancer $lb, $conn ) {
 		$this->lb = $lb;
@@ -1135,6 +1212,7 @@ class DBConnRef implements IDatabase {
 			list( $db, $groups, $wiki ) = $this->params;
 			$this->conn = $this->lb->getConnection( $db, $groups, $wiki );
 		}
+
 		return call_user_func_array( array( $this->conn, $name ), $arguments );
 	}
 
diff --git a/includes/db/LoadMonitor.php b/includes/db/LoadMonitor.php
index 519e2dfd..7281485b 100644
--- a/includes/db/LoadMonitor.php
+++ b/includes/db/LoadMonitor.php
@@ -32,61 +32,35 @@ interface LoadMonitor {
 	 *
 	 * @param LoadBalancer $parent
 	 */
-	function __construct( $parent );
+	public function __construct( $parent );
 
 	/**
 	 * Perform pre-connection load ratio adjustment.
-	 * @param $loads array
-	 * @param string $group the selected query group
-	 * @param $wiki String
+	 * @param array $loads
+	 * @param string|bool $group The selected query group. Default: false
+	 * @param string|bool $wiki Default: false
 	 */
-	function scaleLoads( &$loads, $group = false, $wiki = false );
-
-	/**
-	 * Perform post-connection backoff.
-	 *
-	 * If the connection is in overload, this should return a backoff factor
-	 * which will be used to control polling time. The number of threads
-	 * connected is a good measure.
-	 *
-	 * If there is no overload, zero can be returned.
-	 *
-	 * A threshold thread count is given, the concrete class may compare this
-	 * to the running thread count. The threshold may be false, which indicates
-	 * that the sysadmin has not configured this feature.
-	 *
-	 * @param $conn DatabaseBase
-	 * @param $threshold Float
-	 */
-	function postConnectionBackoff( $conn, $threshold );
+	public function scaleLoads( &$loads, $group = false, $wiki = false );
 
 	/**
 	 * Return an estimate of replication lag for each server
 	 *
-	 * @param $serverIndexes
-	 * @param $wiki
+	 * @param array $serverIndexes
+	 * @param string $wiki
 	 *
 	 * @return array
 	 */
-	function getLagTimes( $serverIndexes, $wiki );
+	public function getLagTimes( $serverIndexes, $wiki );
 }
 
-class LoadMonitor_Null implements LoadMonitor {
-	function __construct( $parent ) {
-	}
-
-	function scaleLoads( &$loads, $group = false, $wiki = false ) {
+class LoadMonitorNull implements LoadMonitor {
+	public function __construct( $parent ) {
 	}
 
-	function postConnectionBackoff( $conn, $threshold ) {
+	public function scaleLoads( &$loads, $group = false, $wiki = false ) {
 	}
 
-	/**
-	 * @param $serverIndexes
-	 * @param $wiki
-	 * @return array
-	 */
-	function getLagTimes( $serverIndexes, $wiki ) {
+	public function getLagTimes( $serverIndexes, $wiki ) {
 		return array_fill_keys( $serverIndexes, 0 );
 	}
 }
@@ -97,58 +71,44 @@ class LoadMonitor_Null implements LoadMonitor {
  *
  * @ingroup Database
  */
-class LoadMonitor_MySQL implements LoadMonitor {
+class LoadMonitorMySQL implements LoadMonitor {
+	/** @var LoadBalancer */
+	public $parent;
+	/** @var BagOStuff */
+	protected $cache;
 
-	/**
-	 * @var LoadBalancer
-	 */
-	var $parent;
+	public function __construct( $parent ) {
+		global $wgMemc;
 
-	/**
-	 * @param LoadBalancer $parent
-	 */
-	function __construct( $parent ) {
 		$this->parent = $parent;
+		$this->cache = $wgMemc ?: wfGetMainCache();
 	}
 
-	/**
-	 * @param $loads
-	 * @param $group bool
-	 * @param $wiki bool
-	 */
-	function scaleLoads( &$loads, $group = false, $wiki = false ) {
+	public function scaleLoads( &$loads, $group = false, $wiki = false ) {
 	}
 
-	/**
-	 * @param $serverIndexes
-	 * @param $wiki
-	 * @return array
-	 */
-	function getLagTimes( $serverIndexes, $wiki ) {
+	public function getLagTimes( $serverIndexes, $wiki ) {
 		if ( count( $serverIndexes ) == 1 && reset( $serverIndexes ) == 0 ) {
 			// Single server only, just return zero without caching
 			return array( 0 => 0 );
 		}
 
-		wfProfileIn( __METHOD__ );
+		$section = new ProfileSection( __METHOD__ );
+
 		$expiry = 5;
 		$requestRate = 10;
 
-		global $wgMemc;
-		if ( empty( $wgMemc ) ) {
-			$wgMemc = wfGetMainCache();
-		}
-
+		$cache = $this->cache;
 		$masterName = $this->parent->getServerName( 0 );
 		$memcKey = wfMemcKey( 'lag_times', $masterName );
-		$times = $wgMemc->get( $memcKey );
+		$times = $cache->get( $memcKey );
 		if ( is_array( $times ) ) {
 			# Randomly recache with probability rising over $expiry
 			$elapsed = time() - $times['timestamp'];
 			$chance = max( 0, ( $expiry - $elapsed ) * $requestRate );
 			if ( mt_rand( 0, $chance ) != 0 ) {
 				unset( $times['timestamp'] ); // hide from caller
-				wfProfileOut( __METHOD__ );
+
 				return $times;
 			}
 			wfIncrStats( 'lag_cache_miss_expired' );
@@ -157,15 +117,15 @@ class LoadMonitor_MySQL implements LoadMonitor {
 		}
 
 		# Cache key missing or expired
-		if ( $wgMemc->add( "$memcKey:lock", 1, 10 ) ) {
+		if ( $cache->add( "$memcKey:lock", 1, 10 ) ) {
 			# Let this process alone update the cache value
-			$unlocker = new ScopedCallback( function() use ( $wgMemc, $memcKey ) {
-				$wgMemc->delete( $memcKey );
+			$unlocker = new ScopedCallback( function () use ( $cache, $memcKey ) {
+				$cache->delete( $memcKey );
 			} );
 		} elseif ( is_array( $times ) ) {
 			# Could not acquire lock but an old cache exists, so use it
 			unset( $times['timestamp'] ); // hide from caller
-			wfProfileOut( __METHOD__ );
+
 			return $times;
 		}
 
@@ -177,34 +137,19 @@ class LoadMonitor_MySQL implements LoadMonitor {
 				$times[$i] = $conn->getLag();
 			} elseif ( false !== ( $conn = $this->parent->openConnection( $i, $wiki ) ) ) {
 				$times[$i] = $conn->getLag();
+				// Close the connection to avoid sleeper connections piling up.
+				// Note that the caller will pick one of these DBs and reconnect,
+				// which is slightly inefficient, but this only matters for the lag
+				// time cache miss cache, which is far less common that cache hits.
+				$this->parent->closeConnection( $conn );
 			}
 		}
 
 		# Add a timestamp key so we know when it was cached
 		$times['timestamp'] = time();
-		$wgMemc->set( $memcKey, $times, $expiry + 10 );
+		$cache->set( $memcKey, $times, $expiry + 10 );
 		unset( $times['timestamp'] ); // hide from caller
 
-		wfProfileOut( __METHOD__ );
 		return $times;
 	}
-
-	/**
-	 * @param $conn DatabaseBase
-	 * @param $threshold
-	 * @return int
-	 */
-	function postConnectionBackoff( $conn, $threshold ) {
-		if ( !$threshold ) {
-			return 0;
-		}
-		$status = $conn->getMysqlStatus( "Thread%" );
-		if ( $status['Threads_running'] > $threshold ) {
-			$server = $conn->getProperty( 'mServer' );
-			wfLogDBError( "LB backoff from $server - Threads_running = {$status['Threads_running']}\n" );
-			return $status['Threads_connected'];
-		} else {
-			return 0;
-		}
-	}
 }
diff --git a/includes/db/ORMIterator.php b/includes/db/ORMIterator.php
index 077eab0f..e8104b6f 100644
--- a/includes/db/ORMIterator.php
+++ b/includes/db/ORMIterator.php
@@ -27,5 +27,4 @@
  * @author Jeroen De Dauw < jeroendedauw@gmail.com >
  */
 interface ORMIterator extends Iterator {
-
 }
diff --git a/includes/db/ORMResult.php b/includes/db/ORMResult.php
index 160033c4..327d20d9 100644
--- a/includes/db/ORMResult.php
+++ b/includes/db/ORMResult.php
@@ -30,14 +30,13 @@
  */
 
 class ORMResult implements ORMIterator {
-
 	/**
 	 * @var ResultWrapper
 	 */
 	protected $res;
 
 	/**
-	 * @var integer
+	 * @var int
 	 */
 	protected $key;
 
@@ -63,7 +62,7 @@ class ORMResult implements ORMIterator {
 	}
 
 	/**
-	 * @param $row
+	 * @param bool|object $row
 	 */
 	protected function setCurrent( $row ) {
 		if ( $row === false ) {
@@ -74,14 +73,14 @@ class ORMResult implements ORMIterator {
 	}
 
 	/**
-	 * @return integer
+	 * @return int
 	 */
 	public function count() {
 		return $this->res->numRows();
 	}
 
 	/**
-	 * @return boolean
+	 * @return bool
 	 */
 	public function isEmpty() {
 		return $this->res->numRows() === 0;
@@ -95,7 +94,7 @@ class ORMResult implements ORMIterator {
 	}
 
 	/**
-	 * @return integer
+	 * @return int
 	 */
 	public function key() {
 		return $this->key;
@@ -114,10 +113,9 @@ class ORMResult implements ORMIterator {
 	}
 
 	/**
-	 * @return boolean
+	 * @return bool
 	 */
 	public function valid() {
 		return $this->current !== false;
 	}
-
 }
diff --git a/includes/db/ORMRow.php b/includes/db/ORMRow.php
index 5ce3794d..b0bade33 100644
--- a/includes/db/ORMRow.php
+++ b/includes/db/ORMRow.php
@@ -32,7 +32,6 @@
  */
 
 class ORMRow implements IORMRow {
-
 	/**
 	 * The fields of the object.
 	 * field name (w/o prefix) => value
@@ -79,7 +78,7 @@ class ORMRow implements IORMRow {
 	 *
 	 * @param IORMTable|null $table Deprecated since 1.22
 	 * @param array|null $fields
-	 * @param boolean $loadDefaults Deprecated since 1.22
+	 * @param bool $loadDefaults Deprecated since 1.22
 	 */
 	public function __construct( IORMTable $table = null, $fields = null, $loadDefaults = false ) {
 		$this->table = $table;
@@ -102,8 +101,8 @@ class ORMRow implements IORMRow {
 	 * @deprecated since 1.22
 	 *
 	 * @param array|null $fields
-	 * @param boolean $override
-	 * @param boolean $skipLoaded
+	 * @param bool $override
+	 * @param bool $skipLoaded
 	 *
 	 * @return bool Success indicator
 	 */
@@ -130,8 +129,10 @@ class ORMRow implements IORMRow {
 
 			if ( $result !== false ) {
 				$this->setFields( $this->table->getFieldsFromDBResult( $result ), $override );
+
 				return true;
 			}
+
 			return false;
 		}
 
@@ -144,7 +145,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 *
 	 * @param string $name Field name
-	 * @param $default mixed: Default value to return when none is found
+	 * @param mixed $default Default value to return when none is found
 	 * (default: null)
 	 *
 	 * @throws MWException
@@ -166,7 +167,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @param $name string
+	 * @param string $name
 	 *
 	 * @return mixed
 	 */
@@ -194,7 +195,7 @@ class ORMRow implements IORMRow {
 	 *
 	 * @since 1.20
 	 *
-	 * @return integer|null
+	 * @return int|null
 	 */
 	public function getId() {
 		return $this->getField( 'id' );
@@ -205,7 +206,7 @@ class ORMRow implements IORMRow {
 	 *
 	 * @since 1.20
 	 *
-	 * @param integer|null $id
+	 * @param int|null $id
 	 */
 	public function setId( $id ) {
 		$this->setField( 'id', $id );
@@ -218,7 +219,7 @@ class ORMRow implements IORMRow {
 	 *
 	 * @param string $name
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function hasField( $name ) {
 		return array_key_exists( $name, $this->fields );
@@ -229,11 +230,10 @@ class ORMRow implements IORMRow {
 	 *
 	 * @since 1.20
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function hasIdField() {
-		return $this->hasField( 'id' )
-			&& !is_null( $this->getField( 'id' ) );
+		return $this->hasField( 'id' ) && !is_null( $this->getField( 'id' ) );
 	}
 
 	/**
@@ -252,7 +252,7 @@ class ORMRow implements IORMRow {
 				$value = $this->fields[$name];
 
 				// Skip null id fields so that the DBMS can set the default.
-				if ( $name === 'id' && is_null ( $value ) ) {
+				if ( $name === 'id' && is_null( $value ) ) {
 					continue;
 				}
 
@@ -278,7 +278,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 *
 	 * @param array $fields The fields to set
-	 * @param boolean $override Override already set fields with the provided values?
+	 * @param bool $override Override already set fields with the provided values?
 	 */
 	public function setFields( array $fields, $override = true ) {
 		foreach ( $fields as $name => $value ) {
@@ -295,7 +295,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 *
 	 * @param null|array $fields
-	 * @param boolean $incNullId
+	 * @param bool $incNullId
 	 *
 	 * @return array
 	 */
@@ -328,7 +328,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @param boolean $override
+	 * @param bool $override
 	 */
 	public function loadDefaults( $override = true ) {
 		$this->setFields( $this->table->getDefaults(), $override );
@@ -343,7 +343,7 @@ class ORMRow implements IORMRow {
 	 *
 	 * @param string|null $functionName
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function save( $functionName = null ) {
 		if ( $this->hasIdField() ) {
@@ -361,7 +361,7 @@ class ORMRow implements IORMRow {
 	 *
 	 * @param string|null $functionName
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	protected function saveExisting( $functionName = null ) {
 		$dbw = $this->table->getWriteDbConnection();
@@ -400,7 +400,7 @@ class ORMRow implements IORMRow {
 	 * @param string|null $functionName
 	 * @param array|null $options
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	protected function insert( $functionName = null, array $options = null ) {
 		$dbw = $this->table->getWriteDbConnection();
@@ -430,7 +430,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22, use IORMTable->removeRow
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function remove() {
 		$this->beforeRemove();
@@ -456,8 +456,9 @@ class ORMRow implements IORMRow {
 
 	/**
 	 * Before removal of an object happens, @see beforeRemove gets called.
-	 * This method loads the fields of which the names have been returned by this one (or all fields if null is returned).
-	 * This allows for loading info needed after removal to get rid of linked data and the like.
+	 * This method loads the fields of which the names have been returned by
+	 * this one (or all fields if null is returned). This allows for loading
+	 * info needed after removal to get rid of linked data and the like.
 	 *
 	 * @since 1.20
 	 *
@@ -523,9 +524,9 @@ class ORMRow implements IORMRow {
 	 * @deprecated since 1.22, use IORMTable->addToField
 	 *
 	 * @param string $field
-	 * @param integer $amount
+	 * @param int $amount
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function addToField( $field, $amount ) {
 		return $this->table->addToField( $this->getUpdateConditions(), $field, $amount );
@@ -552,7 +553,6 @@ class ORMRow implements IORMRow {
 	 * @param array|string|null $summaryFields
 	 */
 	public function loadSummaryFields( $summaryFields = null ) {
-
 	}
 
 	/**
@@ -561,7 +561,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @param boolean $update
+	 * @param bool $update
 	 */
 	public function setUpdateSummaries( $update ) {
 		$this->updateSummaries = $update;
@@ -573,7 +573,7 @@ class ORMRow implements IORMRow {
 	 * @since 1.20
 	 * @deprecated since 1.22
 	 *
-	 * @param boolean $summaryMode
+	 * @param bool $summaryMode
 	 */
 	public function setSummaryMode( $summaryMode ) {
 		$this->inSummaryMode = $summaryMode;
@@ -590,5 +590,4 @@ class ORMRow implements IORMRow {
 	public function getTable() {
 		return $this->table;
 	}
-
 }
diff --git a/includes/db/ORMTable.php b/includes/db/ORMTable.php
index 5f6723b9..2f898b75 100644
--- a/includes/db/ORMTable.php
+++ b/includes/db/ORMTable.php
@@ -29,7 +29,6 @@
  */
 
 class ORMTable extends DBAccessBase implements IORMTable {
-
 	/**
 	 * Cache for instances, used by the singleton method.
 	 *
@@ -81,7 +80,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @var integer DB_ enum
+	 * @var int DB_ enum
 	 */
 	protected $readDb = DB_SLAVE;
 
@@ -96,7 +95,9 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param string|null $rowClass
 	 * @param string $fieldPrefix
 	 */
-	public function __construct( $tableName = '', array $fields = array(), array $defaults = array(), $rowClass = null, $fieldPrefix = '' ) {
+	public function __construct( $tableName = '', array $fields = array(),
+		array $defaults = array(), $rowClass = null, $fieldPrefix = ''
+	) {
 		$this->tableName = $tableName;
 		$this->fields = $fields;
 		$this->defaults = $defaults;
@@ -201,8 +202,10 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @return ORMResult
 	 */
 	public function select( $fields = null, array $conditions = array(),
-							array $options = array(), $functionName = null ) {
+		array $options = array(), $functionName = null
+	) {
 		$res = $this->rawSelect( $fields, $conditions, $options, $functionName );
+
 		return new ORMResult( $this, $res );
 	}
 
@@ -217,11 +220,12 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param array $options
 	 * @param string|null $functionName
 	 *
-	 * @return array of row objects
-	 * @throws DBQueryError if the query failed (even if the database was in ignoreErrors mode).
+	 * @return array Array of row objects
+	 * @throws DBQueryError If the query failed (even if the database was in ignoreErrors mode).
 	 */
 	public function selectObjects( $fields = null, array $conditions = array(),
-								   array $options = array(), $functionName = null ) {
+		array $options = array(), $functionName = null
+	) {
 		$result = $this->selectFields( $fields, $conditions, $options, false, $functionName );
 
 		$objects = array();
@@ -239,19 +243,19 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @since 1.20
 	 *
 	 * @param null|string|array $fields
-	 * @param array             $conditions
-	 * @param array             $options
-	 * @param null|string       $functionName
-	 *
+	 * @param array $conditions
+	 * @param array $options
+	 * @param null|string $functionName
 	 * @return ResultWrapper
-	 * @throws DBQueryError if the quey failed (even if the database was in ignoreErrors mode).
+	 * @throws DBQueryError If the query failed (even if the database was in
+	 *   ignoreErrors mode).
 	 */
 	public function rawSelect( $fields = null, array $conditions = array(),
-							   array $options = array(), $functionName = null ) {
+		array $options = array(), $functionName = null
+	) {
 		if ( is_null( $fields ) ) {
 			$fields = array_keys( $this->getFields() );
-		}
-		else {
+		} else {
 			$fields = (array)$fields;
 		}
 
@@ -307,13 +311,14 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param array|string|null $fields
 	 * @param array $conditions
 	 * @param array $options
-	 * @param boolean $collapse Set to false to always return each result row as associative array.
+	 * @param bool $collapse Set to false to always return each result row as associative array.
 	 * @param string|null $functionName
 	 *
-	 * @return array of array
+	 * @return array Array of array
 	 */
 	public function selectFields( $fields = null, array $conditions = array(),
-								  array $options = array(), $collapse = true, $functionName = null ) {
+		array $options = array(), $collapse = true, $functionName = null
+	) {
 		$objects = array();
 
 		$result = $this->rawSelect( $fields, $conditions, $options, $functionName );
@@ -325,8 +330,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 		if ( $collapse ) {
 			if ( count( $fields ) === 1 ) {
 				$objects = array_map( 'array_shift', $objects );
-			}
-			elseif ( count( $fields ) === 2 ) {
+			} elseif ( count( $fields ) === 2 ) {
 				$o = array();
 
 				foreach ( $objects as $object ) {
@@ -354,7 +358,8 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @return IORMRow|bool False on failure
 	 */
 	public function selectRow( $fields = null, array $conditions = array(),
-							   array $options = array(), $functionName = null ) {
+		array $options = array(), $functionName = null
+	) {
 		$options['LIMIT'] = 1;
 
 		$objects = $this->select( $fields, $conditions, $options, $functionName );
@@ -373,10 +378,11 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param array $options
 	 * @param string|null $functionName
 	 *
-	 * @return ResultWrapper
+	 * @return stdClass
 	 */
 	public function rawSelectRow( array $fields, array $conditions = array(),
-								  array $options = array(), $functionName = null ) {
+		array $options = array(), $functionName = null
+	) {
 		$dbr = $this->getReadDbConnection();
 
 		$result = $dbr->selectRow(
@@ -388,6 +394,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 		);
 
 		$this->releaseConnection( $dbr );
+
 		return $result;
 	}
 
@@ -403,13 +410,14 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param array|string|null $fields
 	 * @param array $conditions
 	 * @param array $options
-	 * @param boolean $collapse Set to false to always return each result row as associative array.
+	 * @param bool $collapse Set to false to always return each result row as associative array.
 	 * @param string|null $functionName
 	 *
 	 * @return mixed|array|bool False on failure
 	 */
 	public function selectFieldsRow( $fields = null, array $conditions = array(),
-									 array $options = array(), $collapse = true, $functionName = null ) {
+		array $options = array(), $collapse = true, $functionName = null
+	) {
 		$options['LIMIT'] = 1;
 
 		$objects = $this->selectFields( $fields, $conditions, $options, $collapse, $functionName );
@@ -425,7 +433,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @param array $conditions
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function has( array $conditions = array() ) {
 		return $this->selectRow( array( 'id' ), $conditions ) !== false;
@@ -436,7 +444,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @since 1.21
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function exists() {
 		$dbr = $this->getReadDbConnection();
@@ -458,7 +466,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param array $conditions
 	 * @param array $options
 	 *
-	 * @return integer
+	 * @return int
 	 */
 	public function count( array $conditions = array(), array $options = array() ) {
 		$res = $this->rawSelectRow(
@@ -479,7 +487,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param array $conditions
 	 * @param string|null $functionName
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function delete( array $conditions, $functionName = null ) {
 		$dbw = $this->getWriteDbConnection();
@@ -491,6 +499,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 		) !== false; // DatabaseBase::delete does not always return true for success as documented...
 
 		$this->releaseConnection( $dbw );
+
 		return $result;
 	}
 
@@ -499,8 +508,8 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @param boolean $requireParams
-	 * @param boolean $setDefaults
+	 * @param bool $requireParams
+	 * @param bool $setDefaults
 	 *
 	 * @return array
 	 */
@@ -535,7 +544,9 @@ class ORMTable extends DBAccessBase implements IORMTable {
 			}
 
 			if ( $setDefaults && $hasDefault ) {
-				$default = is_array( $defaults[$field] ) ? implode( '|', $defaults[$field] ) : $defaults[$field];
+				$default = is_array( $defaults[$field] )
+					? implode( '|', $defaults[$field] )
+					: $defaults[$field];
 				$params[$field][ApiBase::PARAM_DFLT] = $default;
 			}
 		}
@@ -561,16 +572,17 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @return integer DB_ enum
+	 * @return int DB_ enum
 	 */
 	public function getReadDb() {
 		return $this->readDb;
 	}
 
 	/**
-	 * Set the database ID to use for read operations, use DB_XXX constants or an index to the load balancer setup.
+	 * Set the database ID to use for read operations, use DB_XXX constants or
+	 *   an index to the load balancer setup.
 	 *
-	 * @param integer $db
+	 * @param int $db
 	 *
 	 * @since 1.20
 	 */
@@ -583,7 +595,8 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @return String|bool The target wiki, in a form that  LBFactory understands (or false if the local wiki is used)
+	 * @return string|bool The target wiki, in a form that LBFactory understands
+	 *   (or false if the local wiki is used)
 	 */
 	public function getTargetWiki() {
 		return $this->wiki;
@@ -592,7 +605,8 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	/**
 	 * Set the ID of the any foreign wiki to use as a target for database operations
 	 *
-	 * @param string|bool $wiki The target wiki, in a form that  LBFactory understands (or false if the local wiki shall be used)
+	 * @param string|bool $wiki The target wiki, in a form that  LBFactory
+	 *   understands (or false if the local wiki shall be used)
 	 *
 	 * @since 1.20
 	 */
@@ -634,13 +648,15 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @see LoadBalancer::reuseConnection
 	 *
-	 * @param DatabaseBase $db the database
+	 * @param DatabaseBase $db
 	 *
 	 * @since 1.20
 	 */
+	// @codingStandardsIgnoreStart Suppress "useless method overriding" sniffer warning
 	public function releaseConnection( DatabaseBase $db ) {
 		parent::releaseConnection( $db ); // just make it public
 	}
+	// @codingStandardsIgnoreEnd
 
 	/**
 	 * Update the records matching the provided conditions by
@@ -652,7 +668,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param array $values
 	 * @param array $conditions
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function update( array $values, array $conditions = array() ) {
 		$dbw = $this->getWriteDbConnection();
@@ -665,6 +681,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 		) !== false; // DatabaseBase::update does not always return true for success as documented...
 
 		$this->releaseConnection( $dbw );
+
 		return $result;
 	}
 
@@ -711,8 +728,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 				if ( is_array( $value ) ) {
 					$field = $value[0];
 					$value = $value[1];
-				}
-				else {
+				} else {
 					$value = explode( ' ', $value, 2 );
 					$value[0] = $this->getPrefixedField( $value[0] );
 					$prefixedValues[] = implode( ' ', $value );
@@ -732,7 +748,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @since 1.20
 	 *
-	 * @param array|string $fields
+	 * @param array $fields
 	 *
 	 * @return array
 	 */
@@ -809,7 +825,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @since 1.20
 	 *
 	 * @param stdClass $result
-	 *
+	 * @throws MWException
 	 * @return array
 	 */
 	public function getFieldsFromDBResult( stdClass $result ) {
@@ -872,7 +888,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	/**
 	 * @see ORMTable::newRowFromFromDBResult
 	 *
-	 * @deprecated use newRowFromDBResult instead
+	 * @deprecated since 1.20 use newRowFromDBResult instead
 	 * @since 1.20
 	 *
 	 * @param stdClass $result
@@ -899,11 +915,11 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	/**
 	 * @see ORMTable::newRow
 	 *
-	 * @deprecated use newRow instead
+	 * @deprecated since 1.20 use newRow instead
 	 * @since 1.20
 	 *
 	 * @param array $data
-	 * @param boolean $loadDefaults
+	 * @param bool $loadDefaults
 	 *
 	 * @return IORMRow
 	 */
@@ -917,7 +933,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @since 1.20
 	 *
 	 * @param array $fields
-	 * @param boolean $loadDefaults
+	 * @param bool $loadDefaults
 	 *
 	 * @return IORMRow
 	 */
@@ -945,7 +961,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @param string $name
 	 *
-	 * @return boolean
+	 * @return bool
 	 */
 	public function canHaveField( $name ) {
 		return array_key_exists( $name, $this->getFields() );
@@ -959,7 +975,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param IORMRow $row The row to save
 	 * @param string|null $functionName
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function updateRow( IORMRow $row, $functionName = null ) {
 		$dbw = $this->getWriteDbConnection();
@@ -986,7 +1002,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param string|null $functionName
 	 * @param array|null $options
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function insertRow( IORMRow $row, $functionName = null, array $options = null ) {
 		$dbw = $this->getWriteDbConnection();
@@ -1052,7 +1068,7 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 * @param IORMRow $row
 	 * @param string|null $functionName
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 */
 	public function removeRow( IORMRow $row, $functionName = null ) {
 		$success = $this->delete(
@@ -1071,9 +1087,9 @@ class ORMTable extends DBAccessBase implements IORMTable {
 	 *
 	 * @param array $conditions
 	 * @param string $field
-	 * @param integer $amount
+	 * @param int $amount
 	 *
-	 * @return boolean Success indicator
+	 * @return bool Success indicator
 	 * @throws MWException
 	 */
 	public function addToField( array $conditions, $field, $amount ) {
@@ -1103,5 +1119,4 @@ class ORMTable extends DBAccessBase implements IORMTable {
 
 		return $success;
 	}
-
 }