fieldname, with fields acting like * member variables. * * @param $res ResultWrapper|object as returned from DatabaseBase::query(), etc. * @return Row object * @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']. * * @param $res ResultWrapper result object as returned from DatabaseBase::query(), etc. * @return Row object * @throws DBUnexpectedError Thrown if the database returns an error */ function fetchRow( $res ); /** * Get the number of rows in a result object * * @param $res Mixed: A SQL result * @return int */ function numRows( $res ); /** * Get the number of fields in a result object * @see http://www.php.net/mysql_num_fields * * @param $res Mixed: A SQL result * @return int */ function numFields( $res ); /** * 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 * @return string */ function fieldName( $res, $n ); /** * Get the inserted value of an auto-increment row * * The value inserted should be fetched from nextSequenceValue() * * Example: * $id = $dbw->nextSequenceValue('page_page_id_seq'); * $dbw->insert('page',array('page_id' => $id)); * $id = $dbw->insertId(); * * @return int */ function insertId(); /** * 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 */ function dataSeek( $res, $row ); /** * Get the last error number * @see http://www.php.net/mysql_errno * * @return int */ function lastErrno(); /** * Get a description of the last error * @see http://www.php.net/mysql_error * * @return string */ function lastError(); /** * mysql_fetch_field() wrapper * Returns false if the field doesn't exist * * @param $table string: table name * @param $field string: field name * * @return Field */ function fieldInfo( $table, $field ); /** * Get information about an index into an object * @param $table string: Table name * @param $index string: Index name * @param $fname string: Calling function name * @return Mixed: Database-specific index description class or false if the index does not exist */ function indexInfo( $table, $index, $fname = 'Database::indexInfo' ); /** * Get the number of rows affected by the last write query * @see http://www.php.net/mysql_affected_rows * * @return int */ function affectedRows(); /** * Wrapper for addslashes() * * @param $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]"; * 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 */ static function getSoftwareLink(); /** * A string describing the current software version, like from * mysql_get_server_info(). * * @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. * Use getServerVersion() to get machine-friendly information. * * @return string: Version information from the database server */ function getServerInfo(); } /** * Database abstraction object * @ingroup Database */ abstract class DatabaseBase implements DatabaseType { # ------------------------------------------------------------------------------ # Variables # ------------------------------------------------------------------------------ protected $mLastQuery = ''; protected $mDoneWrites = false; protected $mPHPError = false; protected $mServer, $mUser, $mPassword, $mDBname; /** * @var DatabaseBase */ protected $mConn = null; protected $mOpened = false; protected $mTablePrefix; protected $mFlags; protected $mTrxLevel = 0; protected $mErrorCount = 0; protected $mLBInfo = array(); protected $mFakeSlaveLag = null, $mFakeMaster = false; protected $mDefaultBigSelects = null; protected $mSchemaVars = false; # ------------------------------------------------------------------------------ # Accessors # ------------------------------------------------------------------------------ # These optionally set a variable and return the previous state /** * A string describing the current software version, and possibly * 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 */ public function getServerInfo() { return $this->getServerVersion(); } /** * Boolean, controls output of large amounts of debug information. * @param $debug: * - true to enable debugging * - false to disable debugging * - omitted or null to do nothing * * @return The previous value of the flag */ function debug( $debug = null ) { return wfSetBit( $this->mFlags, DBO_DEBUG, $debug ); } /** * Turns buffering of SQL result sets on (true) or off (false). Default is * "on". * * Unbuffered queries are very troublesome in MySQL: * * - If another query is executed while the first query is being read * out, the first query is killed. This means you can't call normal * MediaWiki functions while you are reading an unbuffered query result * from a normal wfGetDB() connection. * * - Unbuffered queries cause the MySQL server to use large amounts of * memory and to hold broad locks which block other queries. * * If you want to limit client-side memory, it's almost always better to * split up queries into batches using a LIMIT clause than to switch off * buffering. * * @param $buffer null|bool * * @return The previous value of the flag */ function bufferResults( $buffer = null ) { if ( is_null( $buffer ) ) { return !(bool)( $this->mFlags & DBO_NOBUFFER ); } else { return !wfSetBit( $this->mFlags, DBO_NOBUFFER, !$buffer ); } } /** * Turns on (false) or off (true) the automatic generation and sending * of a "we're sorry, but there has been a database error" page on * database errors. Default is on (false). When turned off, the * code should use lastErrno() and lastError() to handle the * situation as appropriate. * * @return The previous value of the flag. */ function ignoreErrors( $ignoreErrors = null ) { return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors ); } /** * Gets or sets 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 $level An integer (0 or 1), or omitted to leave it unchanged. * @return The previous value */ function trxLevel( $level = null ) { return wfSetVar( $this->mTrxLevel, $level ); } /** * Get/set the number of errors logged. Only useful when errors are ignored * @param $count The count to set, or omitted to leave it unchanged. * @return The error count */ function errorCount( $count = null ) { return wfSetVar( $this->mErrorCount, $count ); } /** * Get/set the table prefix. * @param $prefix The table prefix to set, or omitted to leave it unchanged. * @return The previous table prefix. */ function tablePrefix( $prefix = null ) { return wfSetVar( $this->mTablePrefix, $prefix, true ); } /** * Get properties passed down from the server info array of the load * balancer. * * @param $name The entry of the info array to get, or null to get the * whole array */ function getLBInfo( $name = null ) { if ( is_null( $name ) ) { return $this->mLBInfo; } else { if ( array_key_exists( $name, $this->mLBInfo ) ) { return $this->mLBInfo[$name]; } else { return null; } } } /** * Set the LB info array, or a member of it. If called with one parameter, * 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 * @return void */ function setLBInfo( $name, $value = null ) { if ( is_null( $value ) ) { $this->mLBInfo = $name; } else { $this->mLBInfo[$name] = $value; } } /** * Set lag time in seconds for a fake slave */ function setFakeSlaveLag( $lag ) { $this->mFakeSlaveLag = $lag; } /** * Make this connection a fake master */ function setFakeMaster( $enabled = true ) { $this->mFakeMaster = $enabled; } /** * Returns true if this database supports (and uses) cascading deletes */ function cascadingDeletes() { return false; } /** * Returns true if this database supports (and uses) triggers (e.g. on the page table) */ function cleanupTriggers() { return false; } /** * Returns true if this database is strict about what can be put into an IP field. * Specifically, it uses a NULL value instead of an empty string. */ function strictIPs() { return false; } /** * Returns true if this database uses timestamps rather than integers */ function realTimestamps() { return false; } /** * Returns true if this database does an implicit sort when doing GROUP BY */ function implicitGroupby() { return true; } /** * Returns true if this database does an implicit order by when the column has an index * For example: SELECT page_title FROM page LIMIT 1 */ function implicitOrderby() { return true; } /** * Returns true if this database requires that SELECT DISTINCT queries require that all ORDER BY expressions occur in the SELECT list per the SQL92 standard */ function standardSelectDistinct() { return true; } /** * Returns true if this database can do a native search on IP columns * e.g. this works as expected: .. WHERE rc_ip = '127.42.12.102/32'; */ function searchableIPs() { return false; } /** * Returns true if this database can use functional indexes */ function functionalIndexes() { return false; } /** * Return the last query that went through DatabaseBase::query() * @return String */ function lastQuery() { return $this->mLastQuery; } /** * Returns true if the connection may have been used for write queries. * Should return true if unsure. * * @return bool */ function doneWrites() { return $this->mDoneWrites; } /** * Is a connection to the database open? * @return Boolean */ function isOpen() { return $this->mOpened; } /** * Set a flag for this connection * * @param $flag Integer: DBO_* constants from Defines.php: * - DBO_DEBUG: output some debug info (same as debug()) * - DBO_NOBUFFER: don't buffer results (inverse of bufferResults()) * - DBO_IGNORE: ignore errors (same as ignoreErrors()) * - 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 */ function setFlag( $flag ) { $this->mFlags |= $flag; } /** * Clear a flag for this connection * * @param $flag: same as setFlag()'s $flag param */ function clearFlag( $flag ) { $this->mFlags &= ~$flag; } /** * Returns a boolean whether the flag $flag is set for this connection * * @param $flag: same as setFlag()'s $flag param * @return Boolean */ function getFlag( $flag ) { return !!( $this->mFlags & $flag ); } /** * General read-only accessor */ function getProperty( $name ) { return $this->$name; } /** * @return string */ function getWikiID() { if ( $this->mTablePrefix ) { return "{$this->mDBname}-{$this->mTablePrefix}"; } else { return $this->mDBname; } } /** * Return a path to the DBMS-specific schema file, otherwise default to tables.sql * * @return string */ public function getSchemaPath() { global $IP; if ( file_exists( "$IP/maintenance/" . $this->getType() . "/tables.sql" ) ) { return "$IP/maintenance/" . $this->getType() . "/tables.sql"; } else { return "$IP/maintenance/tables.sql"; } } # ------------------------------------------------------------------------------ # Other functions # ------------------------------------------------------------------------------ /** * Constructor. * @param $server String: database server host * @param $user String: database user name * @param $password String: database user password * @param $dbName String: database name * @param $flags * @param $tablePrefix String: database table prefixes. By default use the prefix gave in LocalSettings.php */ function __construct( $server = false, $user = false, $password = false, $dbName = false, $flags = 0, $tablePrefix = 'get from global' ) { global $wgDBprefix, $wgCommandLineMode; $this->mFlags = $flags; if ( $this->mFlags & DBO_DEFAULT ) { if ( $wgCommandLineMode ) { $this->mFlags &= ~DBO_TRX; } else { $this->mFlags |= DBO_TRX; } } /** Get the default table prefix*/ if ( $tablePrefix == 'get from global' ) { $this->mTablePrefix = $wgDBprefix; } else { $this->mTablePrefix = $tablePrefix; } if ( $user ) { $this->open( $server, $user, $password, $dbName ); } } /** * Same as new DatabaseMysql( ... ), kept for backward compatibility * @deprecated since 1.17 * * @return DatabaseMysql */ static function newFromParams( $server, $user, $password, $dbName, $flags = 0 ) { wfDeprecated( __METHOD__ ); return new DatabaseMysql( $server, $user, $password, $dbName, $flags ); } /** * Same as new factory( ... ), kept for backward compatibility * @deprecated since 1.18 * @see Database::factory() */ public final static function newFromType( $dbType, $p = array() ) { wfDeprecated( __METHOD__ ); if ( isset( $p['tableprefix'] ) ) { $p['tablePrefix'] = $p['tableprefix']; } return self::factory( $dbType, $p ); } /** * 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( $type ) ); * 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 * database other than the MediaWiki default (such as for external auth, * an extension, et cetera). Do not use this to connect to the MediaWiki * database. Example uses in core: * @see LoadBalancer::reallyOpenConnection() * @see ExternalUser_MediaWiki::initFromCond() * @see ForeignDBRepo::getMasterDB() * @see WebInstaller_DBConnect::execute() * * @param $dbType String A possible DB type * @param $p Array An array of options to pass to the constructor. * Valid options are: host, user, password, dbname, flags, tablePrefix * @return DatabaseBase subclass or null */ public final static function factory( $dbType, $p = array() ) { $canonicalDBTypes = array( 'mysql', 'postgres', 'sqlite', 'oracle', 'mssql', 'ibm_db2' ); $dbType = strtolower( $dbType ); if( in_array( $dbType, $canonicalDBTypes ) ) { $class = 'Database' . ucfirst( $dbType ); 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' ); } else { return null; } } protected function installErrorHandler() { $this->mPHPError = false; $this->htmlErrors = ini_set( 'html_errors', '0' ); set_error_handler( array( $this, 'connectionErrorHandler' ) ); } protected function restoreErrorHandler() { restore_error_handler(); if ( $this->htmlErrors !== false ) { ini_set( 'html_errors', $this->htmlErrors ); } if ( $this->mPHPError ) { $error = preg_replace( '!\[\]!', '', $this->mPHPError ); $error = preg_replace( '!^.*?:(.*)$!', '$1', $error ); return $error; } else { return false; } } protected function connectionErrorHandler( $errno, $errstr ) { $this->mPHPError = $errstr; } /** * Closes a database connection. * if it is open : commits any open transactions * * @return Bool operation success. true if already closed. */ function close() { # Stub, should probably be overridden return true; } /** * @param $error String: fallback error message, used if none is given by DB */ function reportConnectionError( $error = 'Unknown error' ) { $myError = $this->lastError(); if ( $myError ) { $error = $myError; } # New method throw new DBConnectionError( $this, $error ); } /** * The DBMS-dependent part of query() * * @param $sql String: SQL query. * @return Result object to feed to fetchObject, fetchRow, ...; or false on failure */ protected abstract function doQuery( $sql ); /** * Determine whether a query writes to the DB. * Should return true if unsure. * * @return bool */ function isWriteQuery( $sql ) { return !preg_match( '/^(?:SELECT|BEGIN|COMMIT|SET|SHOW|\(SELECT)\b/i', $sql ); } /** * Run an SQL query and return the result. Normally throws a DBQueryError * on failure. If errors are ignored, returns false instead. * * In new code, the query wrappers select(), insert(), update(), delete(), * etc. should be used where possible, since they give much better DBMS * independence and automatically quote or validate user input in a variety * of contexts. This function is generally only useful for queries which are * explicitly DBMS-dependent and are unsupported by the query wrappers, such * as CREATE TABLE. * * 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 * comment (you can use __METHOD__ or add some extra info) * @param $tempIgnore Boolean: Whether to avoid throwing an exception on errors... * maybe best to catch the exception instead? * @return boolean|ResultWrapper. true for a successful write query, ResultWrapper object * for a successful read query, or false on failure if $tempIgnore set * @throws DBQueryError Thrown when the database returns an error of any kind */ public function query( $sql, $fname = '', $tempIgnore = false ) { $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. if ( $isMaster ) { $queryProf = 'query-m: ' . substr( DatabaseBase::generalizeSQL( $sql ), 0, 255 ); $totalProf = 'DatabaseBase::query-master'; } else { $queryProf = 'query: ' . substr( DatabaseBase::generalizeSQL( $sql ), 0, 255 ); $totalProf = 'DatabaseBase::query'; } wfProfileIn( $totalProf ); wfProfileIn( $queryProf ); } $this->mLastQuery = $sql; if ( !$this->mDoneWrites && $this->isWriteQuery( $sql ) ) { # Set a flag indicating that writes have been done wfDebug( __METHOD__ . ": Writes done: $sql\n" ); $this->mDoneWrites = true; } # Add a comment for easy SHOW PROCESSLIST interpretation global $wgUser; if ( is_object( $wgUser ) && $wgUser->isItemLoaded( 'name' ) ) { $userName = $wgUser->getName(); if ( mb_strlen( $userName ) > 15 ) { $userName = mb_substr( $userName, 0, 15 ) . '...'; } $userName = str_replace( '/', '', $userName ); } else { $userName = ''; } $commentedSql = preg_replace( '/\s/', " /* $fname $userName */ ", $sql, 1 ); # If DBO_TRX is set, start a transaction if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() && $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 $sqlstart = substr( $sql, 0, 10 ); // very much worth it, benchmark certified(tm) if ( strpos( $sqlstart, "SHOW " ) !== 0 and strpos( $sqlstart, "SET " ) !== 0 ) $this->begin(); } if ( $this->debug() ) { static $cnt = 0; $cnt++; $sqlx = substr( $commentedSql, 0, 500 ); $sqlx = strtr( $sqlx, "\t\n", ' ' ); if ( $isMaster ) { wfDebug( "Query $cnt (master): $sqlx\n" ); } else { wfDebug( "Query $cnt (slave): $sqlx\n" ); } } if ( istainted( $sql ) & TC_MYSQL ) { throw new MWException( 'Tainted query found' ); } # Do the query and handle errors $ret = $this->doQuery( $commentedSql ); # Try reconnecting if the connection was lost if ( false === $ret && $this->wasErrorReissuable() ) { # Transaction is gone, like it or not $this->mTrxLevel = 0; wfDebug( "Connection lost, reconnecting...\n" ); if ( $this->ping() ) { wfDebug( "Reconnected\n" ); $sqlx = substr( $commentedSql, 0, 500 ); $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" ); } $ret = $this->doQuery( $commentedSql ); } else { wfDebug( "Failed\n" ); } } if ( false === $ret ) { $this->reportQueryError( $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore ); } if ( !Profiler::instance()->isStub() ) { wfProfileOut( $queryProf ); wfProfileOut( $totalProf ); } return $this->resultObject( $ret ); } /** * 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 */ function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) { # Ignore errors during error handling to avoid infinite recursion $ignore = $this->ignoreErrors( true ); ++$this->mErrorCount; if ( $ignore || $tempIgnore ) { 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" ); wfDebug( "SQL ERROR: " . $error . "\n" ); throw new DBQueryError( $this, $error, $errno, $sql, $fname ); } } /** * Intended to be compatible with the PEAR::DB wrapper functions. * http://pear.php.net/manual/en/package.database.db.intro-execute.php * * ? = scalar value, quoted as necessary * ! = raw SQL bit (a function for instance) * & = filename; reads the file and inserts as a blob * (we don't use this though...) * * This function should not be used directly by new code outside of the * database classes. The query wrapper functions (select() etc.) should be * used instead. * * @return array */ 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. */ return array( 'query' => $sql, 'func' => $func ); } /** * Free a prepared query, generated by prepare(). */ function freePrepared( $prepared ) { /* No-op by default */ } /** * Execute a prepared query with the various arguments * @param $prepared String: the prepared sql * @param $args Mixed: Either an array here, or put scalars as varargs * * @return ResultWrapper */ function execute( $prepared, $args = null ) { if ( !is_array( $args ) ) { # Pull the var args $args = func_get_args(); array_shift( $args ); } $sql = $this->fillPrepared( $prepared['query'], $args ); return $this->query( $sql, $prepared['func'] ); } /** * Prepare & execute an SQL statement, quoting and inserting arguments * in the appropriate places. * * This function should not be used directly by new code outside of the * database classes. The query wrapper functions (select() etc.) should be * used instead. * * @param $query String * @param $args ... * * @return ResultWrapper */ function safeQuery( $query, $args = null ) { $prepared = $this->prepare( $query, 'DatabaseBase::safeQuery' ); if ( !is_array( $args ) ) { # Pull the var args $args = func_get_args(); array_shift( $args ); } $retval = $this->execute( $prepared, $args ); $this->freePrepared( $prepared ); return $retval; } /** * For faking prepared SQL statements on DBs that don't support * it directly. * @param $preparedQuery String: a 'preparable' SQL statement * @param $args Array of arguments to fill it with * @return string executable SQL */ function fillPrepared( $preparedQuery, $args ) { reset( $args ); $this->preparedArgs =& $args; return preg_replace_callback( '/(\\\\[?!&]|[?!&])/', array( &$this, 'fillPreparedArg' ), $preparedQuery ); } /** * preg_callback func for fillPrepared() * The arguments should be in $this->preparedArgs and must not be touched * while we're doing this. * * @param $matches Array * @return String * @private */ function fillPreparedArg( $matches ) { switch( $matches[1] ) { case '\\?': return '?'; case '\\!': return '!'; case '\\&': return '&'; } list( /* $n */ , $arg ) = each( $this->preparedArgs ); switch( $matches[1] ) { case '?': return $this->addQuotes( $arg ); case '!': 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.' ); default: throw new DBUnexpectedError( $this, 'Received invalid match. This should never happen!' ); } } /** * Free a result object returned by query() or select(). It's usually not * 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 */ function freeResult( $res ) { } /** * Simple UPDATE wrapper. * Usually throws a DBQueryError on failure. * If errors are explicitly ignored, returns success * * This function exists for historical reasons, DatabaseBase::update() has a more standard * calling convention and feature set * * @return bool */ function set( $table, $var, $value, $cond, $fname = 'DatabaseBase::set' ) { $table = $this->tableName( $table ); $sql = "UPDATE $table SET $var = '" . $this->strencode( $value ) . "' WHERE ($cond)"; return (bool)$this->query( $sql, $fname ); } /** * A SELECT wrapper which returns a single field from a single result row. * * Usually throws a DBQueryError on failure. If errors are explicitly * ignored, returns false on failure. * * If no result rows are returned from the query, false is returned. * * @param $table string|array Table name. See DatabaseBase::select() for details. * @param $var string The field name to select. This must be a valid SQL * fragment: do not use unvalidated user input. * @param $cond string|array The condition array. See DatabaseBase::select() for details. * @param $fname string The function name of the caller. * @param $options string|array The query options. See DatabaseBase::select() for details. * * @return false|mixed The value from the field, or false on failure. */ function selectField( $table, $var, $cond = '', $fname = 'DatabaseBase::selectField', $options = array() ) { if ( !is_array( $options ) ) { $options = array( $options ); } $options['LIMIT'] = 1; $res = $this->select( $table, $var, $cond, $fname, $options ); if ( $res === false || !$this->numRows( $res ) ) { return false; } $row = $this->fetchRow( $res ); if ( $row !== false ) { return reset( $row ); } else { return false; } } /** * Returns an optional USE INDEX clause to go after the table, and a * string to go at the end of the query. * * @param $options Array: associative array of options to be turned into * an SQL query, valid keys are listed in the function. * @return Array * @see DatabaseBase::select() */ function makeSelectOptions( $options ) { $preLimitTail = $postLimitTail = ''; $startOpts = ''; $noKeyOptions = array(); foreach ( $options as $key => $option ) { if ( is_numeric( $key ) ) { $noKeyOptions[$option] = true; } } if ( isset( $options['GROUP BY'] ) ) { $gb = is_array( $options['GROUP BY'] ) ? implode( ',', $options['GROUP BY'] ) : $options['GROUP BY']; $preLimitTail .= " GROUP BY {$gb}"; } if ( isset( $options['HAVING'] ) ) { $preLimitTail .= " HAVING {$options['HAVING']}"; } if ( isset( $options['ORDER BY'] ) ) { $ob = is_array( $options['ORDER BY'] ) ? implode( ',', $options['ORDER BY'] ) : $options['ORDER BY']; $preLimitTail .= " ORDER BY {$ob}"; } // if (isset($options['LIMIT'])) { // $tailOpts .= $this->limitResult('', $options['LIMIT'], // isset($options['OFFSET']) ? $options['OFFSET'] // : false); // } if ( isset( $noKeyOptions['FOR UPDATE'] ) ) { $postLimitTail .= ' FOR UPDATE'; } if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) { $postLimitTail .= ' LOCK IN SHARE MODE'; } if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) { $startOpts .= 'DISTINCT'; } # Various MySQL extensions if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) { $startOpts .= ' /*! STRAIGHT_JOIN */'; } if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) { $startOpts .= ' HIGH_PRIORITY'; } if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) { $startOpts .= ' SQL_BIG_RESULT'; } if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) { $startOpts .= ' SQL_BUFFER_RESULT'; } if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) { $startOpts .= ' SQL_SMALL_RESULT'; } if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) { $startOpts .= ' SQL_CALC_FOUND_ROWS'; } if ( isset( $noKeyOptions['SQL_CACHE'] ) ) { $startOpts .= ' SQL_CACHE'; } if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) { $startOpts .= ' SQL_NO_CACHE'; } if ( isset( $options['USE INDEX'] ) && ! is_array( $options['USE INDEX'] ) ) { $useIndex = $this->useIndexClause( $options['USE INDEX'] ); } else { $useIndex = ''; } return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail ); } /** * Execute a SELECT query constructed using the various parameters provided. * See below for full details of the parameters. * * @param $table String|Array Table name * @param $vars String|Array Field names * @param $conds String|Array Conditions * @param $fname String Caller function name * @param $options Array Query options * @param $join_conds Array Join conditions * * * @param $table string|array * * 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: * * array( 'a' => 'user' ) * * This includes the user table in the query, with the alias "a" available * for use in field names (e.g. a.user_name). * * All of the table names given here are automatically run through * DatabaseBase::tableName(), which causes the table prefix (if any) to be * added, and various other table name mappings to be performed. * * * @param $vars string|array * * May be either a field name or an array of field names. The field names * here are complete fragments of SQL, for direct inclusion into the SELECT * query. Expressions and aliases may be specified as in SQL, for example: * * array( 'MAX(rev_id) AS maxrev' ) * * If an expression is given, care must be taken to ensure that it is * DBMS-independent. * * * @param $conds string|array * * May be either a string containing a single condition, or an array of * conditions. If an array is given, the conditions constructed from each * element are combined with AND. * * Array elements may take one of two forms: * * - Elements with a numeric key are interpreted as raw SQL fragments. * - Elements with a string key are interpreted as equality conditions, * where the key is the field name. * - If the value of such an array element is a scalar (such as a * string), it will be treated as data and thus quoted appropriately. * If it is null, an IS NULL clause will be added. * - If the value is an array, an IN(...) clause will be constructed, * such that the field name may match any of the elements in the * array. The elements of the array will be quoted. * * Note that expressions are often DBMS-dependent in their syntax. * DBMS-independent wrappers are provided for constructing several types of * expression commonly used in condition queries. See: * - DatabaseBase::buildLike() * - DatabaseBase::conditional() * * * @param $options string|array * * Optional: Array of query options. Boolean options are specified by * including them in the array as a string value with a numeric key, for * example: * * array( 'FOR UPDATE' ) * * The supported options are: * * - OFFSET: Skip this many rows at the start of the result set. OFFSET * with LIMIT can theoretically be used for paging through a result set, * but this is discouraged in MediaWiki for performance reasons. * * - LIMIT: Integer: return at most this many rows. The rows are sorted * and then the first rows are taken until the limit is reached. LIMIT * is applied to a result set after OFFSET. * * - FOR UPDATE: Boolean: lock the returned rows so that they can't be * changed until the next COMMIT. * * - DISTINCT: Boolean: return only unique result rows. * * - GROUP BY: May be either an SQL fragment string naming a field or * expression to group by, or an array of such SQL fragments. * * - HAVING: A string containing a HAVING clause. * * - ORDER BY: May be either an SQL fragment giving a field name or * expression to order by, or an array of such SQL fragments. * * - USE INDEX: This may be either a string giving the index name to use * for the query, or an array. If it is an associative array, each key * gives the table name (or alias), each value gives the index name to * use for that table. All strings are SQL fragments and so should be * validated by the caller. * * - EXPLAIN: In MySQL, this causes an EXPLAIN SELECT query to be run, * instead of SELECT. * * And also the following boolean MySQL extensions, see the MySQL manual * for documentation: * * - LOCK IN SHARE MODE * - STRAIGHT_JOIN * - HIGH_PRIORITY * - SQL_BIG_RESULT * - SQL_BUFFER_RESULT * - SQL_SMALL_RESULT * - SQL_CALC_FOUND_ROWS * - SQL_CACHE * - SQL_NO_CACHE * * * @param $join_conds string|array * * Optional associative array of table-specific join conditions. In the * most common case, this is unnecessary, since the join condition can be * in $conds. However, it is useful for doing a LEFT JOIN. * * The key of the array contains the table name or alias. The value is an * array with two elements, numbered 0 and 1. The first gives the type of * join, the second is an SQL fragment giving the join condition for that * table. For example: * * array( 'page' => array('LEFT JOIN','page_latest=rev_id') ) * * @return ResultWrapper. 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. */ function select( $table, $vars, $conds = '', $fname = 'DatabaseBase::select', $options = array(), $join_conds = array() ) { $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds ); return $this->query( $sql, $fname ); } /** * The equivalent of DatabaseBase::select() except that the constructed SQL * is returned, instead of being immediately executed. * * @param $table string|array Table name * @param $vars string|array Field names * @param $conds string|array Conditions * @param $fname string Caller function name * @param $options string|array Query options * @param $join_conds string|array Join conditions * * @return SQL query string. * @see DatabaseBase::select() */ function selectSQLText( $table, $vars, $conds = '', $fname = 'DatabaseBase::select', $options = array(), $join_conds = array() ) { if ( is_array( $vars ) ) { $vars = implode( ',', $vars ); } $options = (array)$options; if ( is_array( $table ) ) { $useIndex = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) ) ? $options['USE INDEX'] : array(); if ( count( $join_conds ) || count( $useIndex ) ) { $from = ' FROM ' . $this->tableNamesWithUseIndexOrJOIN( $table, $useIndex, $join_conds ); } else { $from = ' FROM ' . implode( ',', $this->tableNamesWithAlias( $table ) ); } } elseif ( $table != '' ) { if ( $table { 0 } == ' ' ) { $from = ' FROM ' . $table; } else { $from = ' FROM ' . $this->tableName( $table ); } } else { $from = ''; } list( $startOpts, $useIndex, $preLimitTail, $postLimitTail ) = $this->makeSelectOptions( $options ); if ( !empty( $conds ) ) { if ( is_array( $conds ) ) { $conds = $this->makeList( $conds, LIST_AND ); } $sql = "SELECT $startOpts $vars $from $useIndex WHERE $conds $preLimitTail"; } else { $sql = "SELECT $startOpts $vars $from $useIndex $preLimitTail"; } if ( isset( $options['LIMIT'] ) ) { $sql = $this->limitResult( $sql, $options['LIMIT'], isset( $options['OFFSET'] ) ? $options['OFFSET'] : false ); } $sql = "$sql $postLimitTail"; if ( isset( $options['EXPLAIN'] ) ) { $sql = 'EXPLAIN ' . $sql; } return $sql; } /** * Single row SELECT wrapper. Equivalent to DatabaseBase::select(), except * that a single row object is returned. If the query returns no rows, * false is returned. * * @param $table string|array Table name * @param $vars string|array Field names * @param $conds|array Conditions * @param $fname string Caller function name * @param $options string|array Query options * @param $join_conds array|string Join conditions * * @return ResultWrapper|bool */ function selectRow( $table, $vars, $conds, $fname = 'DatabaseBase::selectRow', $options = array(), $join_conds = array() ) { $options['LIMIT'] = 1; $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds ); if ( $res === false ) { return false; } if ( !$this->numRows( $res ) ) { return false; } $obj = $this->fetchObject( $res ); return $obj; } /** * Estimate 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 * index cardinality statistics, and is notoriously inaccurate, especially * when large numbers of rows have recently been added or deleted. * * For DBMSs that don't support fast result size estimation, this function * will actually perform the SELECT COUNT(*). * * Takes the same arguments as DatabaseBase::select(). * * @param $table String: table name * @param $vars Array: unused * @param $conds Array: filters on the table * @param $fname String: function name for profiling * @param $options Array: options for select * @return Integer: row count */ public function estimateRowCount( $table, $vars = '*', $conds = '', $fname = 'DatabaseBase::estimateRowCount', $options = array() ) { $rows = 0; $res = $this->select ( $table, 'COUNT(*) AS rowcount', $conds, $fname, $options ); 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. * * @param $sql String: A SQL Query */ static function generalizeSQL( $sql ) { # This does the same as the regexp below would do, but in such a way # as to avoid crashing php on some large strings. # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql); $sql = str_replace ( "\\\\", '', $sql ); $sql = str_replace ( "\\'", '', $sql ); $sql = str_replace ( "\\\"", '', $sql ); $sql = preg_replace ( "/'.*'/s", "'X'", $sql ); $sql = preg_replace ( '/".*"/s', "'X'", $sql ); # All newlines, tabs, etc replaced by single space $sql = preg_replace ( '/\s+/', ' ', $sql ); # All numbers => N $sql = preg_replace ( '/-?[0-9]+/s', 'N', $sql ); return $sql; } /** * Determines whether a field exists in a table * * @param $table String: table name * @param $field String: filed to check on that table * @param $fname String: calling function name (optional) * @return Boolean: whether $table has filed $field */ function fieldExists( $table, $field, $fname = 'DatabaseBase::fieldExists' ) { $info = $this->fieldInfo( $table, $field ); return (bool)$info; } /** * Determines whether an index exists * Usually throws a DBQueryError on failure * If errors are explicitly ignored, returns NULL on failure * * @return bool|null */ function indexExists( $table, $index, $fname = 'DatabaseBase::indexExists' ) { $info = $this->indexInfo( $table, $index, $fname ); if ( is_null( $info ) ) { return null; } else { return $info !== false; } } /** * Query whether a given table exists * * @string table * * @return bool */ function tableExists( $table ) { $table = $this->tableName( $table ); $old = $this->ignoreErrors( true ); $res = $this->query( "SELECT 1 FROM $table LIMIT 1", __METHOD__ ); $this->ignoreErrors( $old ); return (bool)$res; } /** * mysql_field_type() wrapper */ 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 * * @return bool */ function indexUnique( $table, $index ) { $indexInfo = $this->indexInfo( $table, $index ); if ( !$indexInfo ) { return null; } return !$indexInfo[0]->Non_unique; } /** * Helper for DatabaseBase::insert(). * * @param $options array * @return string */ function makeInsertOptions( $options ) { return implode( ' ', $options ); } /** * INSERT wrapper, inserts an array into a table. * * $a may be either: * * - A single associative array. The array keys are the field names, and * the values are the values to insert. The values are treated as data * and will be quoted appropriately. If NULL is inserted, this will be * converted to a database NULL. * - An array with numeric keys, holding a list of associative arrays. * This causes a multi-row INSERT on DBMSs that support it. The keys in * each subarray must be identical to each other, and in the same order. * * Usually throws a DBQueryError on failure. If errors are explicitly ignored, * returns success. * * $options is an array of options, with boolean options encoded as values * with numeric keys, in the same style as $options in * DatabaseBase::select(). Supported options are: * * - IGNORE: Boolean: if present, duplicate key errors are ignored, and * any rows which cause duplicate key errors are not inserted. It's * 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 $options Array of options * * @return bool */ function insert( $table, $a, $fname = 'DatabaseBase::insert', $options = array() ) { # No rows to insert, easy just return now if ( !count( $a ) ) { return true; } $table = $this->tableName( $table ); if ( !is_array( $options ) ) { $options = array( $options ); } $options = $this->makeInsertOptions( $options ); if ( isset( $a[0] ) && is_array( $a[0] ) ) { $multi = true; $keys = array_keys( $a[0] ); } else { $multi = false; $keys = array_keys( $a ); } $sql = 'INSERT ' . $options . " INTO $table (" . implode( ',', $keys ) . ') VALUES '; if ( $multi ) { $first = true; foreach ( $a as $row ) { if ( $first ) { $first = false; } else { $sql .= ','; } $sql .= '(' . $this->makeList( $row ) . ')'; } } else { $sql .= '(' . $this->makeList( $a ) . ')'; } return (bool)$this->query( $sql, $fname ); } /** * Make UPDATE options for the DatabaseBase::update function * * @param $options Array: The options passed to DatabaseBase::update * @return string */ function makeUpdateOptions( $options ) { if ( !is_array( $options ) ) { $options = array( $options ); } $opts = array(); if ( in_array( 'LOW_PRIORITY', $options ) ) { $opts[] = $this->lowPriorityOption(); } if ( in_array( 'IGNORE', $options ) ) { $opts[] = 'IGNORE'; } 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 $values Array: 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 $options Array: An array of UPDATE options, can be: * - IGNORE: Ignore unique key conflicts * - LOW_PRIORITY: MySQL-specific, see MySQL manual. * @return Boolean */ function update( $table, $values, $conds, $fname = 'DatabaseBase::update', $options = array() ) { $table = $this->tableName( $table ); $opts = $this->makeUpdateOptions( $options ); $sql = "UPDATE $opts $table SET " . $this->makeList( $values, LIST_SET ); if ( $conds != '*' ) { $sql .= " WHERE " . $this->makeList( $conds, LIST_AND ); } return $this->query( $sql, $fname ); } /** * Makes an encoded list of strings from an array * @param $a Array containing the data * @param $mode: * - 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 * * @return string */ function makeList( $a, $mode = LIST_COMMA ) { if ( !is_array( $a ) ) { throw new DBUnexpectedError( $this, 'DatabaseBase::makeList called with incorrect parameters' ); } $first = true; $list = ''; foreach ( $a as $field => $value ) { if ( !$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' ); } 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; } /** * 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 $data Array: organized as 2-d * array(baseKeyVal => array(subKeyVal => , ...), ...) * @param $baseKey String: field name to match the base-level keys to (eg 'pl_namespace') * @param $subKey String: field name to match the sub-level keys to (eg 'pl_title') * @return Mixed: string SQL fragment, or false if no items in array. */ function makeWhereFrom2d( $data, $baseKey, $subKey ) { $conds = array(); foreach ( $data as $base => $sub ) { if ( count( $sub ) ) { $conds[] = $this->makeList( array( $baseKey => $base, $subKey => array_keys( $sub ) ), LIST_AND ); } } if ( $conds ) { return $this->makeList( $conds, LIST_OR ); } else { // Nothing to search for... return false; } } /** * Bitwise operations */ /** * @param $field * @return string */ function bitNot( $field ) { return "(~$field)"; } /** * @param $fieldLeft * @param $fieldRight * @return string */ function bitAnd( $fieldLeft, $fieldRight ) { return "($fieldLeft & $fieldRight)"; } /** * @param $fieldLeft * @param $fieldRight * @return string */ function bitOr( $fieldLeft, $fieldRight ) { return "($fieldLeft | $fieldRight)"; } /** * Change the current database * * @todo Explain what exactly will fail if this is not overridden. * @return bool Success or failure */ function selectDB( $db ) { # 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 */ function getDBname() { return $this->mDBname; } /** * Get the server hostname or IP address */ function getServer() { return $this->mServer; } /** * Format a table name ready for use in constructing an SQL query * * This does two important things: it quotes the table names to clean them up, * and it adds a table prefix if only given a table name with no quotes. * * All functions of this object which require a table name call this function * themselves. Pass the canonical name to such functions. This is only needed * when calling query() directly. * * @param $name String: database table name * @param $quoted Boolean: Automatically pass the table name through * addIdentifierQuotes() so that it can be used in a query. * @return String: full database name */ function tableName( $name, $quoted = true ) { global $wgSharedDB, $wgSharedPrefix, $wgSharedTables; # 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 # to query a database table with a dot in the name. if ( $this->isQuotedIdentifier( $name ) ) { return $name; } # Lets test for any bits of text that should never show up in a table # name. Basically anything like JOIN or ON which are actually part of # SQL queries, but may end up inside of the table value to combine # sql. Such as how the API is doing. # Note that we use a whitespace test rather than a \b test to avoid # any remote case where a word like on may be inside of a table name # surrounded by symbols which may be considered word breaks. if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) { return $name; } # Split database and table into proper variables. # We reverse the explode so that database.table and table both output # the correct table. $dbDetails = array_reverse( explode( '.', $name, 2 ) ); if ( isset( $dbDetails[1] ) ) { list( $table, $database ) = $dbDetails; } else { list( $table ) = $dbDetails; } $prefix = $this->mTablePrefix; # Default prefix # A database name has been specified in input. We don't want any # prefixes added. if ( isset( $database ) ) { $prefix = ''; } # Note that we use the long format because php will complain in in_array if # the input is not an array, and will complain in is_array if it is not set. if ( !isset( $database ) # Don't use shared database if pre selected. && isset( $wgSharedDB ) # We have a shared database && !$this->isQuotedIdentifier( $table ) # Paranoia check to prevent shared tables listing '`table`' && isset( $wgSharedTables ) && is_array( $wgSharedTables ) && in_array( $table, $wgSharedTables ) ) { # A shared table is selected $database = $wgSharedDB; $prefix = isset( $wgSharedPrefix ) ? $wgSharedPrefix : $prefix; } # Quote the $database and $table and apply the prefix if not quoted. if ( isset( $database ) ) { $database = ( !$quoted || $this->isQuotedIdentifier( $database ) ? $database : $this->addIdentifierQuotes( $database ) ); } $table = "{$prefix}{$table}"; if ( $quoted && !$this->isQuotedIdentifier( $table ) ) { $table = $this->addIdentifierQuotes( "{$table}" ); } # Merge our database and table into our final table name. $tableName = ( isset( $database ) ? "{$database}.{$table}" : "{$table}" ); return $tableName; } /** * Fetch a number of table names into an array * This is handy when you need to construct SQL for joins * * Example: * extract($dbr->tableNames('user','watchlist')); * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user * WHERE wl_user=user_id AND wl_user=$nameWithQuotes"; */ public function tableNames() { $inArray = func_get_args(); $retVal = array(); foreach ( $inArray as $name ) { $retVal[$name] = $this->tableName( $name ); } return $retVal; } /** * Fetch a number of table names into an zero-indexed numerical array * This is handy when you need to construct SQL for joins * * Example: * list( $user, $watchlist ) = $dbr->tableNamesN('user','watchlist'); * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user * WHERE wl_user=user_id AND wl_user=$nameWithQuotes"; */ public function tableNamesN() { $inArray = func_get_args(); $retVal = array(); foreach ( $inArray as $name ) { $retVal[] = $this->tableName( $name ); } return $retVal; } /** * Get an aliased table name * e.g. tableName AS newTableName * * @param $name string Table name, see tableName() * @param $alias string Alias (optional) * @return string SQL name for aliased table. Will not alias a table to its own name */ public function tableNameWithAlias( $name, $alias = false ) { if ( !$alias || $alias == $name ) { return $this->tableName( $name ); } else { return $this->tableName( $name ) . ' ' . $this->addIdentifierQuotes( $alias ); } } /** * Gets an array of aliased table names * * @param $tables array( [alias] => table ) * @return array of strings, see tableNameWithAlias() */ public function tableNamesWithAlias( $tables ) { $retval = array(); foreach ( $tables as $alias => $table ) { if ( is_numeric( $alias ) ) { $alias = $table; } $retval[] = $this->tableNameWithAlias( $table, $alias ); } return $retval; } /** * Get the aliased table name clause for a FROM clause * which might have a JOIN and/or USE INDEX clause * * @param $tables array( [alias] => table ) * @param $use_index array() Same as for select() * @param $join_conds array() Same as for select() * @return string */ protected function tableNamesWithUseIndexOrJOIN( $tables, $use_index = array(), $join_conds = array() ) { $ret = array(); $retJOIN = array(); $use_index = (array)$use_index; $join_conds = (array)$join_conds; foreach ( $tables as $alias => $table ) { if ( !is_string( $alias ) ) { // No alias? Set it equal to the table name $alias = $table; } // Is there a JOIN clause for this table? if ( isset( $join_conds[$alias] ) ) { list( $joinType, $conds ) = $join_conds[$alias]; $tableClause = $joinType; $tableClause .= ' ' . $this->tableNameWithAlias( $table, $alias ); if ( isset( $use_index[$alias] ) ) { // has USE INDEX? $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) ); if ( $use != '' ) { $tableClause .= ' ' . $use; } } $on = $this->makeList( (array)$conds, LIST_AND ); if ( $on != '' ) { $tableClause .= ' ON (' . $on . ')'; } $retJOIN[] = $tableClause; // Is there an INDEX clause for this table? } elseif ( isset( $use_index[$alias] ) ) { $tableClause = $this->tableNameWithAlias( $table, $alias ); $tableClause .= ' ' . $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) ); $ret[] = $tableClause; } else { $tableClause = $this->tableNameWithAlias( $table, $alias ); $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 ) ); } /** * Get the name of an index in a given table * * @param $index * * @return string */ function indexName( $index ) { // Backwards-compatibility hack $renamed = array( 'ar_usertext_timestamp' => 'usertext_timestamp', 'un_user_id' => 'user_id', 'un_user_ip' => 'user_ip', ); if ( isset( $renamed[$index] ) ) { return $renamed[$index]; } else { return $index; } } /** * If it's a string, adds quotes and backslashes * Otherwise returns as-is * * @param $s string * * @return string */ function addQuotes( $s ) { if ( $s === null ) { return 'NULL'; } else { # This will also quote numeric values. This should be harmless, # and protects against weird problems that occur when they really # _are_ strings such as article titles and string->number->string # conversion is not 1:1. return "'" . $this->strencode( $s ) . "'"; } } /** * Quotes an identifier using `backticks` or "double quotes" depending on the database type. * MySQL uses `backticks` while basically everything else uses double quotes. * Since MySQL is the odd one out here the double quotes are our generic * and we implement backticks in DatabaseMysql. * * @return string */ public function addIdentifierQuotes( $s ) { return '"' . str_replace( '"', '""', $s ) . '"'; } /** * Returns if the given identifier looks quoted or not according to * the database convention for quoting identifiers . * * @param $name string * * @return boolean */ public function isQuotedIdentifier( $name ) { return $name[0] == '"' && substr( $name, -1, 1 ) == '"'; } /** * Backwards compatibility, identifier quoting originated in DatabasePostgres * which used quote_ident which does not follow our naming conventions * was renamed to addIdentifierQuotes. * @deprecated since 1.18 use addIdentifierQuotes * * @return string */ function quote_ident( $s ) { wfDeprecated( __METHOD__ ); return $this->addIdentifierQuotes( $s ); } /** * Escape string for safe LIKE usage. * WARNING: you should almost never use this function directly, * instead use buildLike() that escapes everything automatically * @deprecated since 1.17, warnings in 1.17, removed in ??? */ public function escapeLike( $s ) { wfDeprecated( __METHOD__ ); return $this->escapeLikeInternal( $s ); } protected function escapeLikeInternal( $s ) { $s = str_replace( '\\', '\\\\', $s ); $s = $this->strencode( $s ); $s = str_replace( array( '%', '_' ), array( '\%', '\_' ), $s ); return $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. * * 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 */ function buildLike() { $params = func_get_args(); if ( count( $params ) > 0 && is_array( $params[0] ) ) { $params = $params[0]; } $s = ''; foreach ( $params as $value ) { if ( $value instanceof LikeMatch ) { $s .= $value->toString(); } else { $s .= $this->escapeLikeInternal( $value ); } } return " LIKE '" . $s . "' "; } /** * Returns a token for buildLike() that denotes a '_' to be used in a LIKE query * * @return LikeMatch */ function anyChar() { return new LikeMatch( '_' ); } /** * Returns a token for buildLike() that denotes a '%' to be used in a LIKE query * * @rerturn LikeMatch */ function anyString() { return new LikeMatch( '%' ); } /** * Returns an appropriately quoted sequence value for inserting a new row. * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL * subclass will return an integer, and save the value for insertId() */ function nextSequenceValue( $seqName ) { return null; } /** * 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 * MySQL. */ function useIndexClause( $index ) { return ''; } /** * REPLACE query wrapper. * * REPLACE is a very handy MySQL extension, which functions like an INSERT * except that when there is a duplicate key error, the old row is deleted * and the new row is inserted in its place. * * We simulate this with standard SQL with a DELETE followed by INSERT. To * perform the delete, we need to know what the unique indexes are so that * we know how to find the conflicting rows. * * It may be more efficient to leave off unique indexes which are unlikely * to collide. However if you do this, you run the risk of encountering * errors which wouldn't have occurred in MySQL. * * @param $rows Can be either a single row to insert, or multiple rows, * in the same format as for DatabaseBase::insert() * @param $uniqueIndexes is an array of indexes. Each element may be either * a field name or an array of field names * * @param $table String: The table to replace the row(s) in. * @param $uniqueIndexes Array: An associative array of indexes * @param $rows Array: Array of rows to replace * @param $fname String: Calling function name (use __METHOD__) for logs/profiling */ function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseBase::replace' ) { $quotedTable = $this->tableName( $table ); if ( count( $rows ) == 0 ) { return; } # Single row case if ( !is_array( reset( $rows ) ) ) { $rows = array( $rows ); } foreach( $rows as $row ) { # Delete rows which collide if ( $uniqueIndexes ) { $sql = "DELETE FROM $quotedTable WHERE "; $first = true; foreach ( $uniqueIndexes as $index ) { if ( $first ) { $first = false; $sql .= '( '; } else { $sql .= ' ) OR ( '; } if ( is_array( $index ) ) { $first2 = true; foreach ( $index as $col ) { if ( $first2 ) { $first2 = false; } else { $sql .= ' AND '; } $sql .= $col . '=' . $this->addQuotes( $row[$col] ); } } else { $sql .= $index . '=' . $this->addQuotes( $row[$index] ); } } $sql .= ' )'; $this->query( $sql, $fname ); } # Now insert the row $this->insert( $table, $row ); } } /** * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE * statement. * * @param $table Table name * @param $rows Rows to insert * @param $fname Caller function name */ protected function nativeReplace( $table, $rows, $fname ) { $table = $this->tableName( $table ); # Single row case if ( !is_array( reset( $rows ) ) ) { $rows = array( $rows ); } $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES '; $first = true; foreach ( $rows as $row ) { if ( $first ) { $first = false; } else { $sql .= ','; } $sql .= '(' . $this->makeList( $row ) . ')'; } return $this->query( $sql, $fname ); } /** * DELETE where the condition is a join. * * MySQL overrides this to use a multi-table DELETE syntax, in other databases * we use sub-selects * * For safety, an empty $conds will not delete everything. If you want to * delete all rows where the join condition matches, set $conds='*'. * * 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 */ function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'DatabaseBase::deleteJoin' ) { if ( !$conds ) { throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' ); } $delTable = $this->tableName( $delTable ); $joinTable = $this->tableName( $joinTable ); $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable "; if ( $conds != '*' ) { $sql .= 'WHERE ' . $this->makeList( $conds, LIST_AND ); } $sql .= ')'; $this->query( $sql, $fname ); } /** * Returns the size of a text field, or -1 for "unlimited" */ function textFieldSize( $table, $field ) { $table = $this->tableName( $table ); $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";"; $res = $this->query( $sql, 'DatabaseBase::textFieldSize' ); $row = $this->fetchObject( $res ); $m = array(); if ( preg_match( '/\((.*)\)/', $row->Type, $m ) ) { $size = $m[1]; } else { $size = -1; } return $size; } /** * 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 * string and nothing bad should happen. * * @return string Returns the text of the low priority option if it is * supported, or a blank string otherwise */ function lowPriorityOption() { return ''; } /** * DELETE query wrapper. * * @param $table Array Table name * @param $conds String|Array of conditions. See $conds in DatabaseBase::select() for * the format. Use $conds == "*" to delete all rows * @param $fname String name of the calling function * * @return bool */ function delete( $table, $conds, $fname = 'DatabaseBase::delete' ) { if ( !$conds ) { throw new DBUnexpectedError( $this, 'DatabaseBase::delete() called with no conditions' ); } $table = $this->tableName( $table ); $sql = "DELETE FROM $table"; if ( $conds != '*' ) { $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND ); } return $this->query( $sql, $fname ); } /** * INSERT SELECT wrapper. Takes data from a SELECT query and inserts it * into another table. * * @param $destTable The table name to insert into * @param $srcTable May be either a table name, or an array of table names * to include in a join. * * @param $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() * * @param $conds Condition array. See $conds in DatabaseBase::select() for * the details of the format of condition arrays. May be "*" to copy the * whole table. * * @param $fname The function name of the caller, from __METHOD__ * * @param $insertOptions Options for the INSERT part of the query, see * DatabaseBase::insert() for details. * @param $selectOptions Options for the SELECT part of the query, see * DatabaseBase::select() for details. * * @return ResultWrapper */ function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'DatabaseBase::insertSelect', $insertOptions = array(), $selectOptions = array() ) { $destTable = $this->tableName( $destTable ); if ( is_array( $insertOptions ) ) { $insertOptions = implode( ' ', $insertOptions ); } if ( !is_array( $selectOptions ) ) { $selectOptions = array( $selectOptions ); } list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions ); if ( is_array( $srcTable ) ) { $srcTable = implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) ); } else { $srcTable = $this->tableName( $srcTable ); } $sql = "INSERT $insertOptions INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' . " SELECT $startOpts " . implode( ',', $varMap ) . " FROM $srcTable $useIndex "; if ( $conds != '*' ) { $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND ); } $sql .= " $tailOpts"; return $this->query( $sql, $fname ); } /** * 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. For * UPDATE, limitResultForUpdate should be used. * * The version provided by default works in MySQL and SQLite. It will very * likely need to be overridden for most other DBMSes. * * @param $sql String: SQL query we will append the limit too * @param $limit Integer: the SQL limit * @param $offset Integer the SQL offset (default false) * * @return string */ function limitResult( $sql, $limit, $offset = false ) { 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} "; } function limitResultForUpdate( $sql, $num ) { return $this->limitResult( $sql, $num, 0 ); } /** * Returns true if current database backend supports ORDER BY or LIMIT for separate subqueries * within the UNION construct. * @return Boolean */ function unionSupportsOrderAndLimit() { return true; // True for almost every DB supported } /** * Construct a UNION query * This is used for providing overload point for other DB abstractions * not compatible with the MySQL syntax. * @param $sqls Array: SQL statements to combine * @param $all Boolean: use UNION ALL * @return String: SQL fragment */ 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 * to be overridden unless CASE isn't supported in your DBMS. * * @param $cond String: SQL expression which will result in a boolean value * @param $trueVal String: SQL expression to return if true * @param $falseVal String: SQL expression to return if false * @return String: SQL fragment */ function conditional( $cond, $trueVal, $falseVal ) { return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) "; } /** * Returns a comand for str_replace function in SQL query. * Uses REPLACE() in MySQL * * @param $orig String: column to modify * @param $old String: column to seek * @param $new String: column to replace with * * @return string */ function strreplace( $orig, $old, $new ) { return "REPLACE({$orig}, {$old}, {$new})"; } /** * Determines if the last failure was due to a deadlock * STUB * * @return bool */ function wasDeadlock() { return false; } /** * Determines if the last query error was something that should be dealt * with by pinging the connection and reissuing the query. * STUB * * @return bool */ function wasErrorReissuable() { return false; } /** * Determines if the last failure was due to the database being read-only. * STUB * * @return bool */ function wasReadOnlyError() { return false; } /** * Perform a deadlock-prone transaction. * * This function invokes a callback function to perform a set of write * queries. If a deadlock occurs during the processing, the transaction * will be rolled back and the callback function will be called again. * * Usage: * $dbw->deadlockLoop( callback, ... ); * * Extra arguments are passed through to the specified callback function. * * Returns whatever the callback function returned on its successful, * iteration, or false on error, for example if the retry limit was * reached. */ function deadlockLoop() { $myFname = 'DatabaseBase::deadlockLoop'; $this->begin(); $args = func_get_args(); $function = array_shift( $args ); $oldIgnore = $this->ignoreErrors( true ); $tries = DEADLOCK_TRIES; if ( is_array( $function ) ) { $fname = $function[0]; } else { $fname = $function; } do { $retVal = call_user_func_array( $function, $args ); $error = $this->lastError(); $errno = $this->lastErrno(); $sql = $this->lastQuery(); if ( $errno ) { if ( $this->wasDeadlock() ) { # Retry usleep( mt_rand( DEADLOCK_DELAY_MIN, DEADLOCK_DELAY_MAX ) ); } else { $this->reportQueryError( $error, $errno, $sql, $fname ); } } } while ( $this->wasDeadlock() && --$tries > 0 ); $this->ignoreErrors( $oldIgnore ); if ( $tries <= 0 ) { $this->rollback( $myFname ); $this->reportQueryError( $error, $errno, $sql, $fname ); return false; } else { $this->commit( $myFname ); return $retVal; } } /** * 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 * synchronisation * * @return An integer: 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 ) { $fname = 'DatabaseBase::masterPosWait'; wfProfileIn( $fname ); 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( $fname ); return -1; } elseif ( $wait > 0 ) { wfDebug( "Fake slave waiting $wait us\n" ); usleep( $wait ); wfProfileOut( $fname ); return 1; } else { wfDebug( "Fake slave up to date ($wait us)\n" ); wfProfileOut( $fname ); return 0; } } wfProfileOut( $fname ); # Real waits are implemented in the subclass. return 0; } /** * Get the replication position of this slave * * @return DBMasterPos, or false if this is not a slave. */ 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; } } /** * Get the position of this master * * @return DBMasterPos, or false if this is not a master */ function getMasterPos() { if ( $this->mFakeMaster ) { return new MySQLMasterPos( 'fake', microtime( true ) ); } else { return false; } } /** * Begin a transaction, committing any previously open transaction */ function begin( $fname = 'DatabaseBase::begin' ) { $this->query( 'BEGIN', $fname ); $this->mTrxLevel = 1; } /** * End a transaction */ function commit( $fname = 'DatabaseBase::commit' ) { if ( $this->mTrxLevel ) { $this->query( 'COMMIT', $fname ); $this->mTrxLevel = 0; } } /** * Rollback a transaction. * No-op on non-transactional databases. */ function rollback( $fname = 'DatabaseBase::rollback' ) { if ( $this->mTrxLevel ) { $this->query( 'ROLLBACK', $fname, true ); $this->mTrxLevel = 0; } } /** * Creates a new table with structure copied from existing table * Note that unlike most database abstraction functions, this function does not * automatically append database prefix, because it works at a lower * abstraction level. * The table names passed to this function shall not be quoted (this * function calls addIdentifierQuotes when needed). * * @param $oldName String: name of table whose structure should be copied * @param $newName String: name of table to be created * @param $temporary Boolean: whether the new table should be temporary * @param $fname String: calling function name * @return Boolean: true if operation was successful */ function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabaseBase::duplicateTableStructure' ) { throw new MWException( 'DatabaseBase::duplicateTableStructure is not implemented in descendant class' ); } /** * List all tables on the database * * @param $prefix Only show tables with this prefix, e.g. mw_ * @param $fname String: calling function name */ function listTables( $prefix = null, $fname = 'DatabaseBase::listTables' ) { throw new MWException( 'DatabaseBase::listTables is not implemented in descendant class' ); } /** * Convert a timestamp in one of the formats accepted by wfTimestamp() * to the format used for inserting into timestamp fields in this DBMS. * * The result is unquoted, and needs to be passed through addQuotes() * before it can be included in raw SQL. * * @return string */ function timestamp( $ts = 0 ) { return wfTimestamp( TS_MW, $ts ); } /** * Convert a timestamp in one of the formats accepted by wfTimestamp() * to the format used for inserting into timestamp fields in this DBMS. If * NULL is input, it is passed through, allowing NULL values to be inserted * into timestamp fields. * * The result is unquoted, and needs to be passed through addQuotes() * before it can be included in raw SQL. * * @return string */ function timestampOrNull( $ts = null ) { if ( is_null( $ts ) ) { return null; } else { return $this->timestamp( $ts ); } } /** * Take the result from a query, and wrap it in a ResultWrapper if * necessary. Boolean values are passed through as is, to indicate success * of write queries or failure. * * Once upon a time, DatabaseBase::query() returned a bare MySQL result * resource, and it was necessary to call this function to convert it to * a wrapper. Nowadays, raw database objects are never exposed to external * callers, so this is unnecessary in external code. For compatibility with * old code, ResultWrapper objects are passed through unaltered. */ function resultObject( $result ) { if ( empty( $result ) ) { return false; } elseif ( $result instanceof ResultWrapper ) { return $result; } elseif ( $result === true ) { // Successful write query return $result; } else { return new ResultWrapper( $this, $result ); } } /** * Return aggregated value alias */ function aggregateValue ( $valuedata, $valuename = 'value' ) { return $valuename; } /** * Ping the server and try to reconnect if it there is no connection * * @return bool Success or failure */ function ping() { # Stub. Not essential to override. return true; } /** * Get slave lag. Currently supported only by MySQL. * * Note that this function will generate a fatal error on many * installations. Most callers should use LoadBalancer::safeGetLag() * instead. * * @return Database replication lag in seconds */ function getLag() { return intval( $this->mFakeSlaveLag ); } /** * Return the maximum number of items allowed in a list, or 0 for unlimited. * * return int */ function maxListLen() { return 0; } /** * Some DBMSs have a special format for inserting into blob fields, they * 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(). */ function encodeBlob( $b ) { return $b; } /** * Some DBMSs return a special placeholder object representing blob fields * in result objects. Pass the object through this function to return the * original string. */ function decodeBlob( $b ) { return $b; } /** * Override database's default connection timeout. May be useful for very * long batch queries such as full-wiki dumps, where a single query reads * out over hours or days. May or may not be necessary for non-MySQL * databases. For most purposes, leaving it as a no-op should be fine. * * @param $timeout Integer in seconds */ public function setTimeout( $timeout ) {} /** * Read and execute SQL commands from a file. * * Returns true on success, error string or exception on failure (depending * on object's error ignore settings). * * @param $filename String: File name to open * @param $lineCallback Callback: Optional function called before reading each line * @param $resultCallback Callback: Optional function called for each MySQL result * @param $fname String: Calling function name or false if name should be * generated dynamically using $filename */ function sourceFile( $filename, $lineCallback = false, $resultCallback = false, $fname = false ) { wfSuppressWarnings(); $fp = fopen( $filename, 'r' ); wfRestoreWarnings(); if ( false === $fp ) { throw new MWException( "Could not open \"{$filename}\".\n" ); } if ( !$fname ) { $fname = __METHOD__ . "( $filename )"; } try { $error = $this->sourceStream( $fp, $lineCallback, $resultCallback, $fname ); } catch ( MWException $e ) { fclose( $fp ); throw $e; } fclose( $fp ); return $error; } /** * Get the full path of a patch file. Originally based on archive() * from updaters.inc. Keep in mind this always returns a patch, as * it fails back to MySQL if no DB-specific patch can be found * * @param $patch String The name of the patch, like patch-something.sql * @return String Full path to patch file */ public function patchPath( $patch ) { global $IP; $dbType = $this->getType(); if ( file_exists( "$IP/maintenance/$dbType/archives/$patch" ) ) { return "$IP/maintenance/$dbType/archives/$patch"; } else { return "$IP/maintenance/archives/$patch"; } } /** * Set variables to be used in sourceFile/sourceStream, in preference to the * 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 $vars False, or array mapping variable name to value. */ function setSchemaVars( $vars ) { $this->mSchemaVars = $vars; } /** * Read and execute commands from an open file handle. * * 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 line * @param $resultCallback Callback: Optional function called for each MySQL result * @param $fname String: Calling function name */ function sourceStream( $fp, $lineCallback = false, $resultCallback = false, $fname = 'DatabaseBase::sourceStream' ) { $cmd = ""; $done = false; $dollarquote = false; while ( ! feof( $fp ) ) { if ( $lineCallback ) { call_user_func( $lineCallback ); } $line = trim( fgets( $fp ) ); $sl = strlen( $line ) - 1; if ( $sl < 0 ) { continue; } if ( '-' == $line { 0 } && '-' == $line { 1 } ) { continue; } # # Allow dollar quoting for function declarations if ( substr( $line, 0, 4 ) == '$mw$' ) { if ( $dollarquote ) { $dollarquote = false; $done = true; } else { $dollarquote = true; } } elseif ( !$dollarquote ) { if ( ';' == $line { $sl } && ( $sl < 2 || ';' != $line { $sl - 1 } ) ) { $done = true; $line = substr( $line, 0, $sl ); } } if ( $cmd != '' ) { $cmd .= ' '; } $cmd .= "$line\n"; if ( $done ) { $cmd = str_replace( ';;', ";", $cmd ); $cmd = $this->replaceVars( $cmd ); $res = $this->query( $cmd, $fname ); if ( $resultCallback ) { call_user_func( $resultCallback, $res, $this ); } if ( false === $res ) { $err = $this->lastError(); return "Query \"{$cmd}\" failed with error code \"$err\".\n"; } $cmd = ''; $done = false; } } return true; } /** * Database independent variable replacement. Replaces a set of variables * in an SQL statement with their contents as given by $this->getSchemaVars(). * * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables. * * - '{$var}' should be used for text and is passed through the database's * addQuotes method. * - `{$var}` should be used for identifiers (eg: table and database names), * it is passed through the database's addIdentifierQuotes method which * can be overridden if the database uses something other than backticks. * - / *$var* / is just encoded, besides traditional table prefix and * table options its use should be avoided. * * @param $ins String: SQL statement to replace variables in * @return String The new SQL statement with variables replaced */ protected function replaceSchemaVars( $ins ) { $vars = $this->getSchemaVars(); foreach ( $vars as $var => $value ) { // replace '{$var}' $ins = str_replace( '\'{$' . $var . '}\'', $this->addQuotes( $value ), $ins ); // replace `{$var}` $ins = str_replace( '`{$' . $var . '}`', $this->addIdentifierQuotes( $value ), $ins ); // replace /*$var*/ $ins = str_replace( '/*$' . $var . '*/', $this->strencode( $value ) , $ins ); } return $ins; } /** * Replace variables in sourced SQL * * @param $ins string * * @return string */ protected function replaceVars( $ins ) { $ins = $this->replaceSchemaVars( $ins ); // Table prefixes $ins = preg_replace_callback( '!/\*(?:\$wgDBprefix|_)\*/([a-zA-Z_0-9]*)!', array( $this, 'tableNameCallback' ), $ins ); // Index names $ins = preg_replace_callback( '!/\*i\*/([a-zA-Z_0-9]*)!', array( $this, 'indexNameCallback' ), $ins ); return $ins; } /** * Get schema variables. If none have been set via setSchemaVars(), then * use some defaults from the current object. */ protected function getSchemaVars() { if ( $this->mSchemaVars ) { return $this->mSchemaVars; } else { return $this->getDefaultSchemaVars(); } } /** * Get schema variables to use if none have been set via setSchemaVars(). * * Override this in derived classes to provide variables for tables.sql * and SQL patch files. * * @return array */ protected function getDefaultSchemaVars() { return array(); } /** * Table name callback * * @param $matches array * * @return string */ protected function tableNameCallback( $matches ) { return $this->tableName( $matches[1] ); } /** * Index name callback * * @param $matches array * * @return string */ protected function indexNameCallback( $matches ) { return $this->indexName( $matches[1] ); } /** * Build a concatenation list to feed into a SQL query * @param $stringList Array: list of raw SQL expressions; caller is responsible for any quoting * @return String */ function buildConcat( $stringList ) { return 'CONCAT(' . implode( ',', $stringList ) . ')'; } /** * Acquire a named lock * * Abstracted from Filestore::lock() so child classes can implement for * their own needs. * * @param $lockName String: name of lock to aquire * @param $method String: name of method calling us * @param $timeout Integer: timeout * @return Boolean */ public function lock( $lockName, $method, $timeout = 5 ) { return true; } /** * Release a lock. * * @param $lockName String: Name of lock to release * @param $method String: Name of method calling us * * @return Returns 1 if the lock was released, 0 if the lock was not established * by this thread (in which case the lock is not released), and NULL if the named * lock did not exist */ public function unlock( $lockName, $method ) { return true; } /** * Lock specific tables * * @param $read Array of tables to lock for read access * @param $write Array of tables to lock for write access * @param $method String name of caller * @param $lowPriority bool Whether to indicate writes to be LOW PRIORITY * * @return bool */ public function lockTables( $read, $write, $method, $lowPriority = true ) { return true; } /** * Unlock specific tables * * @param $method String the caller * * @return bool */ public function unlockTables( $method ) { return true; } /** * Delete a table * @param $tableName string * @param $fName string * @return bool|ResultWrapper */ public function dropTable( $tableName, $fName = 'DatabaseBase::dropTable' ) { if( !$this->tableExists( $tableName ) ) { return false; } $sql = "DROP TABLE " . $this->tableName( $tableName ); if( $this->cascadingDeletes() ) { $sql .= " CASCADE"; } return $this->query( $sql, $fName ); } /** * Get search engine class. All subclasses of this need to implement this * if they wish to use searching. * * @return String */ public function getSearchEngine() { return 'SearchEngineDummy'; } /** * Find out when 'infinity' is. Most DBMSes support this. This is a special * keyword for timestamps in PostgreSQL, and works with CHAR(14) as well * because "i" sorts after all numbers. * * @return String */ public function getInfinity() { return 'infinity'; } /** * Encode an expiry time * * @param $expiry String: timestamp for expiry, or the 'infinity' string * @return String */ public function encodeExpiry( $expiry ) { if ( $expiry == '' || $expiry == $this->getInfinity() ) { return $this->getInfinity(); } else { return $this->timestamp( $expiry ); } } /** * Allow or deny "big selects" for this session only. This is done by setting * the sql_big_selects session variable. * * This is a MySQL-specific feature. * * @param $value Mixed: true for allow, false for deny, or "default" to * restore the initial value */ public function setBigSelects( $value = true ) { // no-op } }