query(sprintf($q,
$db->addQuotes($wgDBmwschema),
$db->addQuotes($table),
$db->addQuotes($field)));
$row = $db->fetchObject($res);
if (!$row)
return null;
$n = new IBM_DB2Field;
$n->type = $row->typname;
$n->nullable = ($row->attnotnull == 'N');
$n->name = $field;
$n->tablename = $table;
$n->max_length = $row->attlen;
return $n;
}
/**
* Get column name
* @return string column name
*/
function name() { return $this->name; }
/**
* Get table name
* @return string table name
*/
function tableName() { return $this->tablename; }
/**
* Get column type
* @return string column type
*/
function type() { return $this->type; }
/**
* Can column be null?
* @return bool true or false
*/
function nullable() { return $this->nullable; }
/**
* How much can you fit in the column per row?
* @return int length
*/
function maxLength() { return $this->max_length; }
}
/**
* Wrapper around binary large objects
* @ingroup Database
*/
class IBM_DB2Blob {
private $mData;
function __construct($data) {
$this->mData = $data;
}
function getData() {
return $this->mData;
}
}
/**
* Primary database interface
* @ingroup Database
*/
class DatabaseIbm_db2 extends Database {
/*
* Inherited members
protected $mLastQuery = '';
protected $mPHPError = false;
protected $mServer, $mUser, $mPassword, $mConn = null, $mDBname;
protected $mOut, $mOpened = false;
protected $mFailFunction;
protected $mTablePrefix;
protected $mFlags;
protected $mTrxLevel = 0;
protected $mErrorCount = 0;
protected $mLBInfo = array();
protected $mFakeSlaveLag = null, $mFakeMaster = false;
*
*/
/// Server port for uncataloged connections
protected $mPort = NULL;
/// Whether connection is cataloged
protected $mCataloged = NULL;
/// Schema for tables, stored procedures, triggers
protected $mSchema = NULL;
/// Whether the schema has been applied in this session
protected $mSchemaSet = false;
/// Result of last query
protected $mLastResult = NULL;
/// Number of rows affected by last INSERT/UPDATE/DELETE
protected $mAffectedRows = NULL;
/// Number of rows returned by last SELECT
protected $mNumRows = NULL;
const CATALOGED = "cataloged";
const UNCATALOGED = "uncataloged";
const USE_GLOBAL = "get from global";
/// Last sequence value used for a primary key
protected $mInsertId = NULL;
/*
* These can be safely inherited
*
* Getter/Setter: (18)
* failFunction
* setOutputPage
* bufferResults
* ignoreErrors
* trxLevel
* errorCount
* getLBInfo
* setLBInfo
* lastQuery
* isOpen
* setFlag
* clearFlag
* getFlag
* getProperty
* getDBname
* getServer
* tableNameCallback
* tablePrefix
*
* Administrative: (8)
* debug
* installErrorHandler
* restoreErrorHandler
* connectionErrorHandler
* reportConnectionError
* sourceFile
* sourceStream
* replaceVars
*
* Database: (5)
* query
* set
* selectField
* generalizeSQL
* update
* strreplace
* deadlockLoop
*
* Prepared Statement: 6
* prepare
* freePrepared
* execute
* safeQuery
* fillPrepared
* fillPreparedArg
*
* Slave/Master: (4)
* masterPosWait
* getSlavePos
* getMasterPos
* getLag
*
* Generation: (9)
* tableNames
* tableNamesN
* tableNamesWithUseIndexOrJOIN
* escapeLike
* delete
* insertSelect
* timestampOrNull
* resultObject
* aggregateValue
* selectSQLText
* selectRow
* makeUpdateOptions
*
* Reflection: (1)
* indexExists
*/
/*
* These need to be implemented TODO
*
* Administrative: 7 / 7
* constructor [Done]
* open [Done]
* openCataloged [Done]
* close [Done]
* newFromParams [Done]
* openUncataloged [Done]
* setup_database [Done]
*
* Getter/Setter: 13 / 13
* cascadingDeletes [Done]
* cleanupTriggers [Done]
* strictIPs [Done]
* realTimestamps [Done]
* impliciGroupby [Done]
* implicitOrderby [Done]
* searchableIPs [Done]
* functionalIndexes [Done]
* getWikiID [Done]
* isOpen [Done]
* getServerVersion [Done]
* getSoftwareLink [Done]
* getSearchEngine [Done]
*
* Database driver wrapper: 23 / 23
* lastError [Done]
* lastErrno [Done]
* doQuery [Done]
* tableExists [Done]
* fetchObject [Done]
* fetchRow [Done]
* freeResult [Done]
* numRows [Done]
* numFields [Done]
* fieldName [Done]
* insertId [Done]
* dataSeek [Done]
* affectedRows [Done]
* selectDB [Done]
* strencode [Done]
* conditional [Done]
* wasDeadlock [Done]
* ping [Done]
* getStatus [Done]
* setTimeout [Done]
* lock [Done]
* unlock [Done]
* insert [Done]
* select [Done]
*
* Slave/master: 2 / 2
* setFakeSlaveLag [Done]
* setFakeMaster [Done]
*
* Reflection: 6 / 6
* fieldExists [Done]
* indexInfo [Done]
* fieldInfo [Done]
* fieldType [Done]
* indexUnique [Done]
* textFieldSize [Done]
*
* Generation: 16 / 16
* tableName [Done]
* addQuotes [Done]
* makeList [Done]
* makeSelectOptions [Done]
* estimateRowCount [Done]
* nextSequenceValue [Done]
* useIndexClause [Done]
* replace [Done]
* deleteJoin [Done]
* lowPriorityOption [Done]
* limitResult [Done]
* limitResultForUpdate [Done]
* timestamp [Done]
* encodeBlob [Done]
* decodeBlob [Done]
* buildConcat [Done]
*/
######################################
# Getters and Setters
######################################
/**
* Returns true if this database supports (and uses) cascading deletes
*/
function cascadingDeletes() {
return true;
}
/**
* Returns true if this database supports (and uses) triggers (e.g. on the page table)
*/
function cleanupTriggers() {
return true;
}
/**
* 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 true;
}
/**
* Returns true if this database uses timestamps rather than integers
*/
function realTimestamps() {
return true;
}
/**
* Returns true if this database does an implicit sort when doing GROUP BY
*/
function implicitGroupby() {
return false;
}
/**
* 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 false;
}
/**
* 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 true;
}
/**
* Returns true if this database can use functional indexes
*/
function functionalIndexes() {
return true;
}
/**
* Returns a unique string representing the wiki on the server
*/
function getWikiID() {
if( $this->mSchema ) {
return "{$this->mDBname}-{$this->mSchema}";
} else {
return $this->mDBname;
}
}
######################################
# Setup
######################################
/**
*
* @param string $server hostname of database server
* @param string $user username
* @param string $password
* @param string $dbName database name on the server
* @param function $failFunction (optional)
* @param integer $flags database behaviour flags (optional, unused)
*/
public function DatabaseIbm_db2($server = false, $user = false, $password = false,
$dbName = false, $failFunction = false, $flags = 0,
$schema = self::USE_GLOBAL )
{
global $wgOut, $wgDBmwschema;
# Can't get a reference if it hasn't been set yet
if ( !isset( $wgOut ) ) {
$wgOut = NULL;
}
$this->mOut =& $wgOut;
$this->mFailFunction = $failFunction;
$this->mFlags = DBO_TRX | $flags;
if ( $schema == self::USE_GLOBAL ) {
$this->mSchema = $wgDBmwschema;
}
else {
$this->mSchema = $schema;
}
$this->open( $server, $user, $password, $dbName);
}
/**
* Opens a database connection and returns it
* Closes any existing connection
* @return a fresh connection
* @param string $server hostname
* @param string $user
* @param string $password
* @param string $dbName database name
*/
public function open( $server, $user, $password, $dbName )
{
// Load the port number
global $wgDBport_db2, $wgDBcataloged;
wfProfileIn( __METHOD__ );
// Load IBM DB2 driver if missing
if (!@extension_loaded('ibm_db2')) {
@dl('ibm_db2.so');
}
// Test for IBM DB2 support, to avoid suppressed fatal error
if ( !function_exists( 'db2_connect' ) ) {
$error = "DB2 functions missing, have you enabled the ibm_db2 extension for PHP?\n";
wfDebug($error);
$this->reportConnectionError($error);
}
if (!strlen($user)) { // Copied from Postgres
return null;
}
// Close existing connection
$this->close();
// Cache conn info
$this->mServer = $server;
$this->mPort = $port = $wgDBport_db2;
$this->mUser = $user;
$this->mPassword = $password;
$this->mDBname = $dbName;
$this->mCataloged = $cataloged = $wgDBcataloged;
if ( $cataloged == self::CATALOGED ) {
$this->openCataloged($dbName, $user, $password);
}
elseif ( $cataloged == self::UNCATALOGED ) {
$this->openUncataloged($dbName, $user, $password, $server, $port);
}
// Don't do this
// Not all MediaWiki code is transactional
// Rather, turn it off in the begin function and turn on after a commit
// db2_autocommit($this->mConn, DB2_AUTOCOMMIT_OFF);
db2_autocommit($this->mConn, DB2_AUTOCOMMIT_ON);
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 null;
}
$this->mOpened = true;
$this->applySchema();
wfProfileOut( __METHOD__ );
return $this->mConn;
}
/**
* Opens a cataloged database connection, sets mConn
*/
protected function openCataloged( $dbName, $user, $password )
{
@$this->mConn = db2_connect($dbName, $user, $password);
}
/**
* Opens an uncataloged database connection, sets mConn
*/
protected function openUncataloged( $dbName, $user, $password, $server, $port )
{
$str = "DRIVER={IBM DB2 ODBC DRIVER};";
$str .= "DATABASE=$dbName;";
$str .= "HOSTNAME=$server;";
if ($port) $str .= "PORT=$port;";
$str .= "PROTOCOL=TCPIP;";
$str .= "UID=$user;";
$str .= "PWD=$password;";
@$this->mConn = db2_connect($str, $user, $password);
}
/**
* Closes a database connection, if it is open
* Returns success, true if already closed
*/
public function close() {
$this->mOpened = false;
if ( $this->mConn ) {
if ($this->trxLevel() > 0) {
$this->commit();
}
return db2_close( $this->mConn );
}
else {
return true;
}
}
/**
* Returns a fresh instance of this class
* @static
* @return
* @param string $server hostname of database server
* @param string $user username
* @param string $password
* @param string $dbName database name on the server
* @param function $failFunction (optional)
* @param integer $flags database behaviour flags (optional, unused)
*/
static function newFromParams( $server, $user, $password, $dbName, $failFunction = false, $flags = 0)
{
return new DatabaseIbm_db2( $server, $user, $password, $dbName, $failFunction, $flags );
}
/**
* Retrieves the most current database error
* Forces a database rollback
*/
public function lastError() {
if ($this->lastError2()) {
$this->rollback();
return true;
}
return false;
}
private function lastError2() {
$connerr = db2_conn_errormsg();
if ($connerr) return $connerr;
$stmterr = db2_stmt_errormsg();
if ($stmterr) return $stmterr;
if ($this->mConn) return "No open connection.";
if ($this->mOpened) return "No open connection allegedly.";
return false;
}
/**
* Get the last error number
* Return 0 if no error
* @return integer
*/
public function lastErrno() {
$connerr = db2_conn_error();
if ($connerr) return $connerr;
$stmterr = db2_stmt_error();
if ($stmterr) return $stmterr;
return 0;
}
/**
* Is a database connection open?
* @return
*/
public function isOpen() { return $this->mOpened; }
/**
* The DBMS-dependent part of query()
* @param $sql String: SQL query.
* @return object Result object to feed to fetchObject, fetchRow, ...; or false on failure
* @access private
*/
/*private*/
public function doQuery( $sql ) {
//print "$sql
";
// Switch into the correct namespace
$this->applySchema();
$ret = db2_exec( $this->mConn, $sql );
if( !$ret ) {
print "
";
print $sql;
print "
";
$error = db2_stmt_errormsg();
throw new DBUnexpectedError($this, 'SQL error: ' . htmlspecialchars( $error ) );
}
$this->mLastResult = $ret;
$this->mAffectedRows = NULL; // Not calculated until asked for
return $ret;
}
/**
* @return string Version information from the database
*/
public function getServerVersion() {
$info = db2_server_info( $this->mConn );
return $info->DBMS_VER;
}
/**
* Queries whether a given table exists
* @return boolean
*/
public function tableExists( $table ) {
$schema = $this->mSchema;
$sql = <<< EOF
SELECT COUNT(*) FROM SYSIBM.SYSTABLES ST
WHERE ST.NAME = '$table' AND ST.CREATOR = '$schema'
EOF;
$res = $this->query( $sql );
if (!$res) return false;
// If the table exists, there should be one of it
@$row = $this->fetchRow($res);
$count = $row[0];
if ($count == '1' or $count == 1) {
return true;
}
return false;
}
/**
* Fetch the next row from the given result object, in object form.
* Fields can be retrieved with $row->fieldname, with fields acting like
* member variables.
*
* @param $res SQL result object as returned from Database::query(), etc.
* @return DB2 row object
* @throws DBUnexpectedError Thrown if the database returns an error
*/
public function fetchObject( $res ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
@$row = db2_fetch_object( $res );
if( $this->lastErrno() ) {
throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
}
// Make field names lowercase for compatibility with MySQL
if ($row)
{
$row2 = new BlankObject();
foreach ($row as $key => $value)
{
$keyu = strtolower($key);
$row2->$keyu = $value;
}
$row = $row2;
}
return $row;
}
/**
* Fetch the next row from the given result object, in associative array
* form. Fields are retrieved with $row['fieldname'].
*
* @param $res SQL result object as returned from Database::query(), etc.
* @return DB2 row object
* @throws DBUnexpectedError Thrown if the database returns an error
*/
public function fetchRow( $res ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
@$row = db2_fetch_array( $res );
if ( $this->lastErrno() ) {
throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
}
return $row;
}
/**
* Override if introduced to base Database class
*/
public function initial_setup() {
// do nothing
}
/**
* Create tables, stored procedures, and so on
*/
public function setup_database() {
// Timeout was being changed earlier due to mysterious crashes
// Changing it now may cause more problems than not changing it
//set_time_limit(240);
try {
// TODO: switch to root login if available
// Switch into the correct namespace
$this->applySchema();
$this->begin();
$res = dbsource( "../maintenance/ibm_db2/tables.sql", $this);
$res = null;
// TODO: update mediawiki_version table
// TODO: populate interwiki links
$this->commit();
}
catch (MWException $mwe)
{
print "
$mwe
";
}
}
/**
* Escapes strings
* Doesn't escape numbers
* @param string s string to escape
* @return escaped string
*/
public function addQuotes( $s ) {
//wfDebug("DB2::addQuotes($s)\n");
if ( is_null( $s ) ) {
return "NULL";
} else if ($s instanceof Blob) {
return "'".$s->fetch($s)."'";
}
$s = $this->strencode($s);
if ( is_numeric($s) ) {
return $s;
}
else {
return "'$s'";
}
}
/**
* Escapes strings
* Only escapes numbers going into non-numeric fields
* @param string s string to escape
* @return escaped string
*/
public function addQuotesSmart( $table, $field, $s ) {
if ( is_null( $s ) ) {
return "NULL";
} else if ($s instanceof Blob) {
return "'".$s->fetch($s)."'";
}
$s = $this->strencode($s);
if ( is_numeric($s) ) {
// Check with the database if the column is actually numeric
// This allows for numbers in titles, etc
$res = $this->doQuery("SELECT $field FROM $table FETCH FIRST 1 ROWS ONLY");
$type = db2_field_type($res, strtoupper($field));
if ( $this->is_numeric_type( $type ) ) {
//wfDebug("DB2: Numeric value going in a numeric column: $s in $type $field in $table\n");
return $s;
}
else {
wfDebug("DB2: Numeric in non-numeric: '$s' in $type $field in $table\n");
return "'$s'";
}
}
else {
return "'$s'";
}
}
/**
* Verifies that a DB2 column/field type is numeric
* @return bool true if numeric
* @param string $type DB2 column type
*/
public function is_numeric_type( $type ) {
switch (strtoupper($type)) {
case 'SMALLINT':
case 'INTEGER':
case 'INT':
case 'BIGINT':
case 'DECIMAL':
case 'REAL':
case 'DOUBLE':
case 'DECFLOAT':
return true;
}
return false;
}
/**
* Alias for addQuotes()
* @param string s string to escape
* @return escaped string
*/
public function strencode( $s ) {
// Bloody useless function
// Prepends backslashes to \x00, \n, \r, \, ', " and \x1a.
// But also necessary
$s = db2_escape_string($s);
// Wide characters are evil -- some of them look like '
$s = utf8_encode($s);
// Fix its stupidity
$from = array("\\\\", "\\'", '\\n', '\\t', '\\"', '\\r');
$to = array("\\", "''", "\n", "\t", '"', "\r");
$s = str_replace($from, $to, $s); // DB2 expects '', not \' escaping
return $s;
}
/**
* Switch into the database schema
*/
protected function applySchema() {
if ( !($this->mSchemaSet) ) {
$this->mSchemaSet = true;
$this->begin();
$this->doQuery("SET SCHEMA = $this->mSchema");
$this->commit();
}
}
/**
* Start a transaction (mandatory)
*/
public function begin() {
// turn off auto-commit
db2_autocommit($this->mConn, DB2_AUTOCOMMIT_OFF);
$this->mTrxLevel = 1;
}
/**
* End a transaction
* Must have a preceding begin()
*/
public function commit() {
db2_commit($this->mConn);
// turn auto-commit back on
db2_autocommit($this->mConn, DB2_AUTOCOMMIT_ON);
$this->mTrxLevel = 0;
}
/**
* Cancel a transaction
*/
public function rollback() {
db2_rollback($this->mConn);
// turn auto-commit back on
// not sure if this is appropriate
db2_autocommit($this->mConn, DB2_AUTOCOMMIT_ON);
$this->mTrxLevel = 0;
}
/**
* Makes an encoded list of strings from an array
* $mode:
* LIST_COMMA - comma separated, no field names
* LIST_AND - ANDed WHERE clause (without the WHERE)
* 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
*/
public function makeList( $a, $mode = LIST_COMMA ) {
wfDebug("DB2::makeList()\n");
if ( !is_array( $a ) ) {
throw new DBUnexpectedError( $this, 'Database::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($value).") ";
}
} elseif( is_null($value) ) {
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 = ";
}
if ( $mode == LIST_NAMES ) {
$list .= $value;
}
// Leo: Can't insert quoted numbers into numeric columns
// (?) Might cause other problems. May have to check column type before insertion.
else if ( is_numeric($value) ) {
$list .= $value;
}
else {
$list .= $this->addQuotes( $value );
}
}
}
return $list;
}
/**
* Makes an encoded list of strings from an array
* Quotes numeric values being inserted into non-numeric fields
* @return string
* @param string $table name of the table
* @param array $a list of values
* @param $mode:
* LIST_COMMA - comma separated, no field names
* LIST_AND - ANDed WHERE clause (without the WHERE)
* 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
*/
public function makeListSmart( $table, $a, $mode = LIST_COMMA ) {
if ( !is_array( $a ) ) {
throw new DBUnexpectedError( $this, 'Database::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($value).") ";
}
} elseif( is_null($value) ) {
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 = ";
}
if ( $mode == LIST_NAMES ) {
$list .= $value;
}
else {
$list .= $this->addQuotesSmart( $table, $field, $value );
}
}
}
return $list;
}
/**
* 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
* $offset integer the SQL offset (default false)
*/
public function limitResult($sql, $limit, $offset=false) {
if( !is_numeric($limit) ) {
throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" );
}
if( $offset ) {
wfDebug("Offset parameter not supported in limitResult()\n");
}
// TODO implement proper offset handling
// idea: get all the rows between 0 and offset, advance cursor to offset
return "$sql FETCH FIRST $limit ROWS ONLY ";
}
/**
* Handle reserved keyword replacement in table names
* @return
* @param $name Object
*/
public function tableName( $name ) {
# Replace reserved words with better ones
switch( $name ) {
case 'user':
return 'mwuser';
case 'text':
return 'pagecontent';
default:
return $name;
}
}
/**
* Generates a timestamp in an insertable format
* @return string timestamp value
* @param timestamp $ts
*/
public function timestamp( $ts=0 ) {
// TS_MW cannot be easily distinguished from an integer
return wfTimestamp(TS_DB2,$ts);
}
/**
* Return the next in a sequence, save the value for retrieval via insertId()
* @param string seqName Name of a defined sequence in the database
* @return next value in that sequence
*/
public function nextSequenceValue( $seqName ) {
$safeseq = preg_replace( "/'/", "''", $seqName );
$res = $this->query( "VALUES NEXTVAL FOR $safeseq" );
$row = $this->fetchRow( $res );
$this->mInsertId = $row[0];
$this->freeResult( $res );
return $this->mInsertId;
}
/**
* This must be called after nextSequenceVal
* @return Last sequence value used as a primary key
*/
public function insertId() {
return $this->mInsertId;
}
/**
* INSERT wrapper, inserts an array into a table
*
* $args may be a single associative array, or an array of these with numeric keys,
* for multi-row insert
*
* @param array $table String: Name of the table to insert to.
* @param array $args Array: Items to insert into the table.
* @param array $fname String: Name of the function, for profiling
* @param mixed $options String or Array. Valid options: IGNORE
*
* @return bool Success of insert operation. IGNORE always returns true.
*/
public function insert( $table, $args, $fname = 'DatabaseIbm_db2::insert', $options = array() ) {
wfDebug("DB2::insert($table)\n");
if ( !count( $args ) ) {
return true;
}
$table = $this->tableName( $table );
if ( !is_array( $options ) )
$options = array( $options );
if ( isset( $args[0] ) && is_array( $args[0] ) ) {
}
else {
$args = array($args);
}
$keys = array_keys( $args[0] );
// If IGNORE is set, we use savepoints to emulate mysql's behavior
$ignore = in_array( 'IGNORE', $options ) ? 'mw' : '';
// Cache autocommit value at the start
$oldautocommit = db2_autocommit($this->mConn);
// If we are not in a transaction, we need to be for savepoint trickery
$didbegin = 0;
if (! $this->mTrxLevel) {
$this->begin();
$didbegin = 1;
}
if ( $ignore ) {
$olde = error_reporting( 0 );
// For future use, we may want to track the number of actual inserts
// Right now, insert (all writes) simply return true/false
$numrowsinserted = 0;
}
$sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
if ( !$ignore ) {
$first = true;
foreach ( $args as $row ) {
if ( $first ) {
$first = false;
} else {
$sql .= ',';
}
$sql .= '(' . $this->makeListSmart( $table, $row ) . ')';
}
$res = (bool)$this->query( $sql, $fname, $ignore );
}
else {
$res = true;
$origsql = $sql;
foreach ( $args as $row ) {
$tempsql = $origsql;
$tempsql .= '(' . $this->makeListSmart( $table, $row ) . ')';
if ( $ignore ) {
db2_exec($this->mConn, "SAVEPOINT $ignore");
}
$tempres = (bool)$this->query( $tempsql, $fname, $ignore );
if ( $ignore ) {
$bar = db2_stmt_error();
if ($bar != false) {
db2_exec( $this->mConn, "ROLLBACK TO SAVEPOINT $ignore" );
}
else {
db2_exec( $this->mConn, "RELEASE SAVEPOINT $ignore" );
$numrowsinserted++;
}
}
// If any of them fail, we fail overall for this function call
// Note that this will be ignored if IGNORE is set
if (! $tempres)
$res = false;
}
}
if ($didbegin) {
$this->commit();
}
// if autocommit used to be on, it's ok to commit everything
else if ($oldautocommit)
{
$this->commit();
}
if ( $ignore ) {
$olde = error_reporting( $olde );
// Set the affected row count for the whole operation
$this->mAffectedRows = $numrowsinserted;
// IGNORE always returns true
return true;
}
return $res;
}
/**
* UPDATE wrapper, takes a condition array and a SET array
*
* @param string $table The table to UPDATE
* @param array $values An array of values to SET
* @param array $conds An array of conditions (WHERE). Use '*' to update all rows.
* @param string $fname The Class::Function calling this function
* (for the log)
* @param array $options An array of UPDATE options, can be one or
* more of IGNORE, LOW_PRIORITY
* @return bool
*/
function update( $table, $values, $conds, $fname = 'Database::update', $options = array() ) {
$table = $this->tableName( $table );
$opts = $this->makeUpdateOptions( $options );
$sql = "UPDATE $opts $table SET " . $this->makeListSmart( $table, $values, LIST_SET );
if ( $conds != '*' ) {
$sql .= " WHERE " . $this->makeListSmart( $table, $conds, LIST_AND );
}
return $this->query( $sql, $fname );
}
/**
* DELETE query wrapper
*
* Use $conds == "*" to delete all rows
*/
function delete( $table, $conds, $fname = 'Database::delete' ) {
if ( !$conds ) {
throw new DBUnexpectedError( $this, 'Database::delete() called with no conditions' );
}
$table = $this->tableName( $table );
$sql = "DELETE FROM $table";
if ( $conds != '*' ) {
$sql .= ' WHERE ' . $this->makeListSmart( $table, $conds, LIST_AND );
}
return $this->query( $sql, $fname );
}
/**
* Returns the number of rows affected by the last query or 0
* @return int the number of rows affected by the last query
*/
public function affectedRows() {
if ( !is_null( $this->mAffectedRows ) ) {
// Forced result for simulated queries
return $this->mAffectedRows;
}
if( empty( $this->mLastResult ) )
return 0;
return db2_num_rows( $this->mLastResult );
}
/**
* USE INDEX clause
* DB2 doesn't have them and returns ""
* @param sting $index
*/
public function useIndexClause( $index ) {
return "";
}
/**
* Simulates REPLACE with a DELETE followed by INSERT
* @param $table Object
* @param array $uniqueIndexes array consisting of indexes and arrays of indexes
* @param array $rows Rows to insert
* @param string $fname Name of the function for profiling
* @return nothing
*/
function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseIbm_db2::replace' ) {
$table = $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 $table 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
$sql = "INSERT INTO $table (" . $this->makeList( array_keys( $row ), LIST_NAMES ) .') VALUES (' .
$this->makeList( $row, LIST_COMMA ) . ')';
$this->query( $sql, $fname );
}
}
/**
* Returns the number of rows in the result set
* Has to be called right after the corresponding select query
* @param Object $res result set
* @return int number of rows
*/
public function numRows( $res ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
if ( $this->mNumRows ) {
return $this->mNumRows;
}
else {
return 0;
}
}
/**
* Moves the row pointer of the result set
* @param Object $res result set
* @param int $row row number
* @return success or failure
*/
public function dataSeek( $res, $row ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
return db2_fetch_row( $res, $row );
}
###
# Fix notices in Block.php
###
/**
* Frees memory associated with a statement resource
* @param Object $res Statement resource to free
* @return bool success or failure
*/
public function freeResult( $res ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
if ( !@db2_free_result( $res ) ) {
throw new DBUnexpectedError($this, "Unable to free DB2 result\n" );
}
}
/**
* Returns the number of columns in a resource
* @param Object $res Statement resource
* @return Number of fields/columns in resource
*/
public function numFields( $res ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
return db2_num_fields( $res );
}
/**
* Returns the nth column name
* @param Object $res Statement resource
* @param int $n Index of field or column
* @return string name of nth column
*/
public function fieldName( $res, $n ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
return db2_field_name( $res, $n );
}
/**
* SELECT wrapper
*
* @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
*/
public function select( $table, $vars, $conds='', $fname = 'DatabaseIbm_db2::select', $options = array(), $join_conds = array() )
{
$res = parent::select( $table, $vars, $conds, $fname, $options, $join_conds );
// We must adjust for offset
if ( isset( $options['LIMIT'] ) ) {
if ( isset ($options['OFFSET'] ) ) {
$limit = $options['LIMIT'];
$offset = $options['OFFSET'];
}
}
// DB2 does not have a proper num_rows() function yet, so we must emulate it
// DB2 9.5.3/9.5.4 and the corresponding ibm_db2 driver will introduce a working one
// Yay!
// we want the count
$vars2 = array('count(*) as num_rows');
// respecting just the limit option
$options2 = array();
if ( isset( $options['LIMIT'] ) ) $options2['LIMIT'] = $options['LIMIT'];
// but don't try to emulate for GROUP BY
if ( isset( $options['GROUP BY'] ) ) return $res;
$res2 = parent::select( $table, $vars2, $conds, $fname, $options2, $join_conds );
$obj = $this->fetchObject($res2);
$this->mNumRows = $obj->num_rows;
wfDebug("DatabaseIbm_db2::select: There are $this->mNumRows rows.\n");
return $res;
}
/**
* Handles ordering, grouping, and having options ('GROUP BY' => colname)
* Has limited support for per-column options (colnum => 'DISTINCT')
*
* @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
*/
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'] ) ) $preLimitTail .= " GROUP BY {$options['GROUP BY']}";
if ( isset( $options['HAVING'] ) ) $preLimitTail .= " HAVING {$options['HAVING']}";
if ( isset( $options['ORDER BY'] ) ) $preLimitTail .= " ORDER BY {$options['ORDER BY']}";
if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) $startOpts .= 'DISTINCT';
return array( $startOpts, '', $preLimitTail, $postLimitTail );
}
/**
* Returns link to IBM DB2 free download
* @return string wikitext of a link to the server software's web site
*/
public function getSoftwareLink() {
return "[http://www.ibm.com/software/data/db2/express/?s_cmp=ECDDWW01&s_tact=MediaWiki IBM DB2]";
}
/**
* Does nothing
* @param object $db
* @return bool true
*/
public function selectDB( $db ) {
return true;
}
/**
* Returns an SQL expression for a simple conditional.
* Uses CASE on DB2
*
* @param string $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
*/
public function conditional( $cond, $trueVal, $falseVal ) {
return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
}
###
# Fix search crash
###
/**
* Get search engine class. All subclasses of this
* need to implement this if they wish to use searching.
*
* @return string
*/
public function getSearchEngine() {
return "SearchIBM_DB2";
}
###
# Tuesday the 14th of October, 2008
###
/**
* Did the last database access fail because of deadlock?
* @return bool
*/
public function wasDeadlock() {
// get SQLSTATE
$err = $this->lastErrno();
switch($err) {
case '40001': // sql0911n, Deadlock or timeout, rollback
case '57011': // sql0904n, Resource unavailable, no rollback
case '57033': // sql0913n, Deadlock or timeout, no rollback
wfDebug("In a deadlock because of SQLSTATE $err");
return true;
}
return false;
}
/**
* Ping the server and try to reconnect if it there is no connection
* The connection may be closed and reopened while this happens
* @return bool whether the connection exists
*/
public function ping() {
// db2_ping() doesn't exist
// Emulate
$this->close();
if ($this->mCataloged == NULL) {
return false;
}
else if ($this->mCataloged) {
$this->mConn = $this->openCataloged($this->mDBName, $this->mUser, $this->mPassword);
}
else if (!$this->mCataloged) {
$this->mConn = $this->openUncataloged($this->mDBName, $this->mUser, $this->mPassword, $this->mServer, $this->mPort);
}
return false;
}
######################################
# Unimplemented and not applicable
######################################
/**
* Not implemented
* @return string ''
* @deprecated
*/
public function getStatus( $which ) { wfDebug('Not implemented for DB2: getStatus()'); return ''; }
/**
* Not implemented
* @deprecated
*/
public function setTimeout( $timeout ) { wfDebug('Not implemented for DB2: setTimeout()'); }
/**
* Not implemented
* TODO
* @return bool true
*/
public function lock( $lockName, $method ) { wfDebug('Not implemented for DB2: lock()'); return true; }
/**
* Not implemented
* TODO
* @return bool true
*/
public function unlock( $lockName, $method ) { wfDebug('Not implemented for DB2: unlock()'); return true; }
/**
* Not implemented
* @deprecated
*/
public function setFakeSlaveLag( $lag ) { wfDebug('Not implemented for DB2: setFakeSlaveLag()'); }
/**
* Not implemented
* @deprecated
*/
public function setFakeMaster( $enabled ) { wfDebug('Not implemented for DB2: setFakeMaster()'); }
/**
* Not implemented
* @return string $sql
* @deprecated
*/
public function limitResultForUpdate($sql, $num) { return $sql; }
/**
* No such option
* @return string ''
* @deprecated
*/
public function lowPriorityOption() { return ''; }
######################################
# Reflection
######################################
/**
* Query whether a given column exists in the mediawiki schema
* @param string $table name of the table
* @param string $field name of the column
* @param string $fname function name for logging and profiling
*/
public function fieldExists( $table, $field, $fname = 'DatabaseIbm_db2::fieldExists' ) {
$table = $this->tableName( $table );
$schema = $this->mSchema;
$etable = preg_replace("/'/", "''", $table);
$eschema = preg_replace("/'/", "''", $schema);
$ecol = preg_replace("/'/", "''", $field);
$sql = <<query( $sql, $fname );
$count = $res ? $this->numRows($res) : 0;
if ($res)
$this->freeResult( $res );
return $count;
}
/**
* Returns information about an index
* If errors are explicitly ignored, returns NULL on failure
* @param string $table table name
* @param string $index index name
* @param string
* @return object query row in object form
*/
public function indexInfo( $table, $index, $fname = 'DatabaseIbm_db2::indexExists' ) {
$table = $this->tableName( $table );
$sql = <<query( $sql, $fname );
if ( !$res ) {
return NULL;
}
$row = $this->fetchObject( $res );
if ($row != NULL) return $row;
else return false;
}
/**
* Returns an information object on a table column
* @param string $table table name
* @param string $field column name
* @return IBM_DB2Field
*/
public function fieldInfo( $table, $field ) {
return IBM_DB2Field::fromText($this, $table, $field);
}
/**
* db2_field_type() wrapper
* @param Object $res Result of executed statement
* @param mixed $index number or name of the column
* @return string column type
*/
public function fieldType( $res, $index ) {
if ( $res instanceof ResultWrapper ) {
$res = $res->result;
}
return db2_field_type( $res, $index );
}
/**
* Verifies that an index was created as unique
* @param string $table table name
* @param string $index index name
* @param string $fnam function name for profiling
* @return bool
*/
public function indexUnique ($table, $index, $fname = 'Database::indexUnique' ) {
$table = $this->tableName( $table );
$sql = <<query( $sql, $fname );
if ( !$res ) {
return null;
}
if ($this->fetchObject( $res )) {
return true;
}
return false;
}
/**
* Returns the size of a text field, or -1 for "unlimited"
* @param string $table table name
* @param string $field column name
* @return int length or -1 for unlimited
*/
public function textFieldSize( $table, $field ) {
$table = $this->tableName( $table );
$sql = <<query($sql);
$row = $this->fetchObject($res);
$size = $row->size;
$this->freeResult( $res );
return $size;
}
/**
* DELETE where the condition is a join
* @param string $delTable deleting from this table
* @param string $joinTable using data from this table
* @param string $delVar variable in deleteable table
* @param string $joinVar variable in data table
* @param array $conds conditionals for join table
* @param string $fname function name for profiling
*/
public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = "DatabaseIbm_db2::deleteJoin" ) {
if ( !$conds ) {
throw new DBUnexpectedError($this, 'Database::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 );
}
/**
* Estimate rows in dataset
* Returns estimated count, based on COUNT(*) output
* Takes same arguments as Database::select()
* @param string $table table name
* @param array $vars unused
* @param array $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 = 'Database::estimateRowCount', $options = array() ) {
$rows = 0;
$res = $this->select ($table, 'COUNT(*) as mwrowcount', $conds, $fname, $options );
if ($res) {
$row = $this->fetchRow($res);
$rows = (isset($row['mwrowcount'])) ? $row['mwrowcount'] : 0;
}
$this->freeResult($res);
return $rows;
}
/**
* Description is left as an exercise for the reader
* @param mixed $b data to be encoded
* @return IBM_DB2Blob
*/
public function encodeBlob($b) {
return new IBM_DB2Blob($b);
}
/**
* Description is left as an exercise for the reader
* @param IBM_DB2Blob $b data to be decoded
* @return mixed
*/
public function decodeBlob($b) {
return $b->getData();
}
/**
* Convert into a list of string being concatenated
* @param array $stringList strings that need to be joined together by the SQL engine
* @return string joined by the concatenation operator
*/
public function buildConcat( $stringList ) {
// || is equivalent to CONCAT
// Sample query: VALUES 'foo' CONCAT 'bar' CONCAT 'baz'
return implode( ' || ', $stringList );
}
/**
* Generates the SQL required to convert a DB2 timestamp into a Unix epoch
* @param string $column name of timestamp column
* @return string SQL code
*/
public function extractUnixEpoch( $column ) {
// TODO
// see SpecialAncientpages
}
}
?>