3 * @defgroup Database Database
7 * This file deals with database interface functions
8 * and query specifics/optimisations
11 /** Number of times to re-try an operation in case of deadlock */
12 define( 'DEADLOCK_TRIES', 4 );
13 /** Minimum time to wait before retry, in microseconds */
14 define( 'DEADLOCK_DELAY_MIN', 500000 );
15 /** Maximum time to wait before retry */
16 define( 'DEADLOCK_DELAY_MAX', 1500000 );
19 * Base interface for all DBMS-specific code. At a bare minimum, all of the
20 * following must be implemented to support MediaWiki
25 interface DatabaseType {
27 * Get the type of the DBMS, as it appears in $wgDBtype.
31 public function getType();
34 * Open a connection to the database. Usually aborts on failure
36 * @param $server String: database server host
37 * @param $user String: database user name
38 * @param $password String: database user password
39 * @param $dbName String: database name
41 * @throws DBConnectionError
43 public function open( $server, $user, $password, $dbName );
46 * The DBMS-dependent part of query()
47 * @todo Fixme: Make this private someday
49 * @param $sql String: SQL query.
50 * @return Result object to feed to fetchObject, fetchRow, ...; or false on failure
53 /*private*/ function doQuery( $sql );
56 * Fetch the next row from the given result object, in object form.
57 * Fields can be retrieved with $row->fieldname, with fields acting like
60 * @param $res SQL result object as returned from DatabaseBase::query(), etc.
62 * @throws DBUnexpectedError Thrown if the database returns an error
64 public function fetchObject( $res );
67 * Fetch the next row from the given result object, in associative array
68 * form. Fields are retrieved with $row['fieldname'].
70 * @param $res SQL result object as returned from DatabaseBase::query(), etc.
72 * @throws DBUnexpectedError Thrown if the database returns an error
74 public function fetchRow( $res );
77 * Get the number of rows in a result object
79 * @param $res Mixed: A SQL result
82 public function numRows( $res );
85 * Get the number of fields in a result object
86 * @see http://www.php.net/mysql_num_fields
88 * @param $res Mixed: A SQL result
91 public function numFields( $res );
94 * Get a field name in a result object
95 * @see http://www.php.net/mysql_field_name
97 * @param $res Mixed: A SQL result
101 public function fieldName( $res, $n );
104 * Get the inserted value of an auto-increment row
106 * The value inserted should be fetched from nextSequenceValue()
109 * $id = $dbw->nextSequenceValue('page_page_id_seq');
110 * $dbw->insert('page',array('page_id' => $id));
111 * $id = $dbw->insertId();
115 public function insertId();
118 * Change the position of the cursor in a result object
119 * @see http://www.php.net/mysql_data_seek
121 * @param $res Mixed: A SQL result
122 * @param $row Mixed: Either MySQL row or ResultWrapper
124 public function dataSeek( $res, $row );
127 * Get the last error number
128 * @see http://www.php.net/mysql_errno
132 public function lastErrno();
135 * Get a description of the last error
136 * @see http://www.php.net/mysql_error
140 public function lastError();
143 * mysql_fetch_field() wrapper
144 * Returns false if the field doesn't exist
146 * @param $table string: table name
147 * @param $field string: field name
149 public function fieldInfo( $table, $field );
152 * Get information about an index into an object
153 * @param $table string: Table name
154 * @param $index string: Index name
155 * @param $fname string: Calling function name
156 * @return Mixed: Database-specific index description class or false if the index does not exist
158 function indexInfo( $table, $index, $fname = 'Database::indexInfo' );
161 * Get the number of rows affected by the last write query
162 * @see http://www.php.net/mysql_affected_rows
166 public function affectedRows();
169 * Wrapper for addslashes()
171 * @param $s string: to be slashed.
172 * @return string: slashed string.
174 public function strencode( $s );
177 * Returns a wikitext link to the DB's website, e.g.,
178 * return "[http://www.mysql.com/ MySQL]";
179 * Should at least contain plain text, if for some reason
180 * your database has no website.
182 * @return string: wikitext of a link to the server software's web site
184 public static function getSoftwareLink();
187 * A string describing the current software version, like from
188 * mysql_get_server_info().
190 * @return string: Version information from the database server.
192 public function getServerVersion();
195 * A string describing the current software version, and possibly
196 * other details in a user-friendly way. Will be listed on Special:Version, etc.
197 * Use getServerVersion() to get machine-friendly information.
199 * @return string: Version information from the database server
201 public function getServerInfo();
205 * Database abstraction object
208 abstract class DatabaseBase implements DatabaseType {
210 # ------------------------------------------------------------------------------
212 # ------------------------------------------------------------------------------
214 protected $mLastQuery = '';
215 protected $mDoneWrites = false;
216 protected $mPHPError = false;
218 protected $mServer, $mUser, $mPassword, $mConn = null, $mDBname;
219 protected $mOpened = false;
221 protected $mTablePrefix;
223 protected $mTrxLevel = 0;
224 protected $mErrorCount = 0;
225 protected $mLBInfo = array();
226 protected $mFakeSlaveLag = null, $mFakeMaster = false;
227 protected $mDefaultBigSelects = null;
228 protected $mSchemaVars = false;
230 # ------------------------------------------------------------------------------
232 # ------------------------------------------------------------------------------
233 # These optionally set a variable and return the previous state
236 * A string describing the current software version, and possibly
237 * other details in a user-friendly way. Will be listed on Special:Version, etc.
238 * Use getServerVersion() to get machine-friendly information.
240 * @return string: Version information from the database server
242 public function getServerInfo() {
243 return $this->getServerVersion();
247 * Boolean, controls output of large amounts of debug information
249 function debug( $debug = null ) {
250 return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
254 * Turns buffering of SQL result sets on (true) or off (false).
255 * Default is "on" and it should not be changed without good reasons.
257 function bufferResults( $buffer = null ) {
258 if ( is_null( $buffer ) ) {
259 return !(bool)( $this->mFlags & DBO_NOBUFFER );
261 return !wfSetBit( $this->mFlags, DBO_NOBUFFER, !$buffer );
266 * Turns on (false) or off (true) the automatic generation and sending
267 * of a "we're sorry, but there has been a database error" page on
268 * database errors. Default is on (false). When turned off, the
269 * code should use lastErrno() and lastError() to handle the
270 * situation as appropriate.
272 function ignoreErrors( $ignoreErrors = null ) {
273 return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors );
277 * The current depth of nested transactions
278 * @param $level Integer: , default NULL.
280 function trxLevel( $level = null ) {
281 return wfSetVar( $this->mTrxLevel, $level );
285 * Number of errors logged, only useful when errors are ignored
287 function errorCount( $count = null ) {
288 return wfSetVar( $this->mErrorCount, $count );
291 function tablePrefix( $prefix = null ) {
292 return wfSetVar( $this->mTablePrefix, $prefix );
296 * Properties passed down from the server info array of the load balancer
298 function getLBInfo( $name = null ) {
299 if ( is_null( $name ) ) {
300 return $this->mLBInfo;
302 if ( array_key_exists( $name, $this->mLBInfo ) ) {
303 return $this->mLBInfo[$name];
310 function setLBInfo( $name, $value = null ) {
311 if ( is_null( $value ) ) {
312 $this->mLBInfo = $name;
314 $this->mLBInfo[$name] = $value;
319 * Set lag time in seconds for a fake slave
321 function setFakeSlaveLag( $lag ) {
322 $this->mFakeSlaveLag = $lag;
326 * Make this connection a fake master
328 function setFakeMaster( $enabled = true ) {
329 $this->mFakeMaster = $enabled;
333 * Returns true if this database supports (and uses) cascading deletes
335 function cascadingDeletes() {
340 * Returns true if this database supports (and uses) triggers (e.g. on the page table)
342 function cleanupTriggers() {
347 * Returns true if this database is strict about what can be put into an IP field.
348 * Specifically, it uses a NULL value instead of an empty string.
350 function strictIPs() {
355 * Returns true if this database uses timestamps rather than integers
357 function realTimestamps() {
362 * Returns true if this database does an implicit sort when doing GROUP BY
364 function implicitGroupby() {
369 * Returns true if this database does an implicit order by when the column has an index
370 * For example: SELECT page_title FROM page LIMIT 1
372 function implicitOrderby() {
377 * Returns true if this database requires that SELECT DISTINCT queries require that all
378 ORDER BY expressions occur in the SELECT list per the SQL92 standard
380 function standardSelectDistinct() {
385 * Returns true if this database can do a native search on IP columns
386 * e.g. this works as expected: .. WHERE rc_ip = '127.42.12.102/32';
388 function searchableIPs() {
393 * Returns true if this database can use functional indexes
395 function functionalIndexes() {
400 * Return the last query that went through DatabaseBase::query()
403 function lastQuery() { return $this->mLastQuery; }
407 * Returns true if the connection may have been used for write queries.
408 * Should return true if unsure.
410 function doneWrites() { return $this->mDoneWrites; }
413 * Is a connection to the database open?
416 function isOpen() { return $this->mOpened; }
419 * Set a flag for this connection
421 * @param $flag Integer: DBO_* constants from Defines.php:
422 * - DBO_DEBUG: output some debug info (same as debug())
423 * - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
424 * - DBO_IGNORE: ignore errors (same as ignoreErrors())
425 * - DBO_TRX: automatically start transactions
426 * - DBO_DEFAULT: automatically sets DBO_TRX if not in command line mode
427 * and removes it in command line mode
428 * - DBO_PERSISTENT: use persistant database connection
430 function setFlag( $flag ) {
431 $this->mFlags |= $flag;
435 * Clear a flag for this connection
437 * @param $flag: same as setFlag()'s $flag param
439 function clearFlag( $flag ) {
440 $this->mFlags &= ~$flag;
444 * Returns a boolean whether the flag $flag is set for this connection
446 * @param $flag: same as setFlag()'s $flag param
449 function getFlag( $flag ) {
450 return !!( $this->mFlags & $flag );
454 * General read-only accessor
456 function getProperty( $name ) {
460 function getWikiID() {
461 if ( $this->mTablePrefix ) {
462 return "{$this->mDBname}-{$this->mTablePrefix}";
464 return $this->mDBname;
469 * Return a path to the DBMS-specific schema, otherwise default to tables.sql
471 public function getSchema() {
473 if ( file_exists( "$IP/maintenance/" . $this->getType() . "/tables.sql" ) ) {
474 return "$IP/maintenance/" . $this->getType() . "/tables.sql";
476 return "$IP/maintenance/tables.sql";
480 # ------------------------------------------------------------------------------
482 # ------------------------------------------------------------------------------
486 * @param $server String: database server host
487 * @param $user String: database user name
488 * @param $password String: database user password
489 * @param $dbName String: database name
491 * @param $tablePrefix String: database table prefixes. By default use the prefix gave in LocalSettings.php
493 function __construct( $server = false, $user = false, $password = false, $dbName = false,
494 $flags = 0, $tablePrefix = 'get from global'
496 global $wgOut, $wgDBprefix, $wgCommandLineMode;
498 # Can't get a reference if it hasn't been set yet
499 if ( !isset( $wgOut ) ) {
502 $this->mFlags = $flags;
504 if ( $this->mFlags & DBO_DEFAULT ) {
505 if ( $wgCommandLineMode ) {
506 $this->mFlags &= ~DBO_TRX;
508 $this->mFlags |= DBO_TRX;
513 // Faster read-only access
514 if ( wfReadOnly() ) {
515 $this->mFlags |= DBO_PERSISTENT;
516 $this->mFlags &= ~DBO_TRX;
519 /** Get the default table prefix*/
520 if ( $tablePrefix == 'get from global' ) {
521 $this->mTablePrefix = $wgDBprefix;
523 $this->mTablePrefix = $tablePrefix;
527 $this->open( $server, $user, $password, $dbName );
532 * Same as new DatabaseMysql( ... ), kept for backward compatibility
535 static function newFromParams( $server, $user, $password, $dbName, $flags = 0 ) {
536 wfDeprecated( __METHOD__ );
537 return new DatabaseMysql( $server, $user, $password, $dbName, $flags );
541 * Given a DB type, construct the name of the appropriate child class of
542 * DatabaseBase. This is designed to replace all of the manual stuff like:
543 * $class = 'Database' . ucfirst( strtolower( $type ) );
544 * as well as validate against the canonical list of DB types we have
546 * This factory function is mostly useful for when you need to connect to a
547 * database other than the MediaWiki default (such as for external auth,
548 * an extension, et cetera). Do not use this to connect to the MediaWiki
549 * database. Example uses in core:
550 * @see LoadBalancer::reallyOpenConnection()
551 * @see ExternalUser_MediaWiki::initFromCond()
552 * @see ForeignDBRepo::getMasterDB()
553 * @see WebInstaller_DBConnect::execute()
555 * @param $dbType String A possible DB type
556 * @param $p Array An array of options to pass to the constructor.
557 * Valid options are: host, user, password, dbname, flags, tableprefix
558 * @return DatabaseBase subclass or null
560 public final static function newFromType( $dbType, $p = array() ) {
561 $canonicalDBTypes = array(
562 'mysql', 'postgres', 'sqlite', 'oracle', 'mssql', 'ibm_db2'
564 $dbType = strtolower( $dbType );
566 if( in_array( $dbType, $canonicalDBTypes ) ) {
567 $class = 'Database' . ucfirst( $dbType );
569 isset( $p['host'] ) ? $p['host'] : false,
570 isset( $p['user'] ) ? $p['user'] : false,
571 isset( $p['password'] ) ? $p['password'] : false,
572 isset( $p['dbname'] ) ? $p['dbname'] : false,
573 isset( $p['flags'] ) ? $p['flags'] : 0,
574 isset( $p['tableprefix'] ) ? $p['tableprefix'] : 'get from global'
581 protected function installErrorHandler() {
582 $this->mPHPError = false;
583 $this->htmlErrors = ini_set( 'html_errors', '0' );
584 set_error_handler( array( $this, 'connectionErrorHandler' ) );
587 protected function restoreErrorHandler() {
588 restore_error_handler();
589 if ( $this->htmlErrors !== false ) {
590 ini_set( 'html_errors', $this->htmlErrors );
592 if ( $this->mPHPError ) {
593 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->mPHPError );
594 $error = preg_replace( '!^.*?:(.*)$!', '$1', $error );
601 protected function connectionErrorHandler( $errno, $errstr ) {
602 $this->mPHPError = $errstr;
606 * Closes a database connection.
607 * if it is open : commits any open transactions
609 * @return Bool operation success. true if already closed.
612 # Stub, should probably be overridden
617 * @param $error String: fallback error message, used if none is given by DB
619 function reportConnectionError( $error = 'Unknown error' ) {
620 $myError = $this->lastError();
626 throw new DBConnectionError( $this, $error );
630 * Determine whether a query writes to the DB.
631 * Should return true if unsure.
633 function isWriteQuery( $sql ) {
634 return !preg_match( '/^(?:SELECT|BEGIN|COMMIT|SET|SHOW|\(SELECT)\b/i', $sql );
638 * Usually aborts on failure. If errors are explicitly ignored, returns success.
640 * @param $sql String: SQL query
641 * @param $fname String: Name of the calling function, for profiling/SHOW PROCESSLIST
642 * comment (you can use __METHOD__ or add some extra info)
643 * @param $tempIgnore Boolean: Whether to avoid throwing an exception on errors...
644 * maybe best to catch the exception instead?
645 * @return boolean or ResultWrapper. true for a successful write query, ResultWrapper object for a successful read query,
646 * or false on failure if $tempIgnore set
647 * @throws DBQueryError Thrown when the database returns an error of any kind
649 public function query( $sql, $fname = '', $tempIgnore = false ) {
652 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
653 if ( isset( $wgProfiler ) ) {
654 # generalizeSQL will probably cut down the query to reasonable
655 # logging size most of the time. The substr is really just a sanity check.
657 # Who's been wasting my precious column space? -- TS
658 # $profName = 'query: ' . $fname . ' ' . substr( DatabaseBase::generalizeSQL( $sql ), 0, 255 );
661 $queryProf = 'query-m: ' . substr( DatabaseBase::generalizeSQL( $sql ), 0, 255 );
662 $totalProf = 'DatabaseBase::query-master';
664 $queryProf = 'query: ' . substr( DatabaseBase::generalizeSQL( $sql ), 0, 255 );
665 $totalProf = 'DatabaseBase::query';
668 wfProfileIn( $totalProf );
669 wfProfileIn( $queryProf );
672 $this->mLastQuery = $sql;
673 if ( !$this->mDoneWrites && $this->isWriteQuery( $sql ) ) {
674 // Set a flag indicating that writes have been done
675 wfDebug( __METHOD__ . ": Writes done: $sql\n" );
676 $this->mDoneWrites = true;
679 # Add a comment for easy SHOW PROCESSLIST interpretation
682 if ( is_object( $wgUser ) && $wgUser->mDataLoaded ) {
683 $userName = $wgUser->getName();
684 if ( mb_strlen( $userName ) > 15 ) {
685 $userName = mb_substr( $userName, 0, 15 ) . '...';
687 $userName = str_replace( '/', '', $userName );
691 $commentedSql = preg_replace( '/\s/', " /* $fname $userName */ ", $sql, 1 );
693 # $commentedSql = $sql;
696 # If DBO_TRX is set, start a transaction
697 if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() &&
698 $sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK' ) {
699 // avoid establishing transactions for SHOW and SET statements too -
700 // that would delay transaction initializations to once connection
701 // is really used by application
702 $sqlstart = substr( $sql, 0, 10 ); // very much worth it, benchmark certified(tm)
703 if ( strpos( $sqlstart, "SHOW " ) !== 0 and strpos( $sqlstart, "SET " ) !== 0 )
707 if ( $this->debug() ) {
711 $sqlx = substr( $commentedSql, 0, 500 );
712 $sqlx = strtr( $sqlx, "\t\n", ' ' );
715 wfDebug( "Query $cnt (master): $sqlx\n" );
717 wfDebug( "Query $cnt (slave): $sqlx\n" );
721 if ( istainted( $sql ) & TC_MYSQL ) {
722 throw new MWException( 'Tainted query found' );
725 # Do the query and handle errors
726 $ret = $this->doQuery( $commentedSql );
728 # Try reconnecting if the connection was lost
729 if ( false === $ret && $this->wasErrorReissuable() ) {
730 # Transaction is gone, like it or not
731 $this->mTrxLevel = 0;
732 wfDebug( "Connection lost, reconnecting...\n" );
734 if ( $this->ping() ) {
735 wfDebug( "Reconnected\n" );
736 $sqlx = substr( $commentedSql, 0, 500 );
737 $sqlx = strtr( $sqlx, "\t\n", ' ' );
738 global $wgRequestTime;
739 $elapsed = round( microtime( true ) - $wgRequestTime, 3 );
740 if ( $elapsed < 300 ) {
741 # Not a database error to lose a transaction after a minute or two
742 wfLogDBError( "Connection lost and reconnected after {$elapsed}s, query: $sqlx\n" );
744 $ret = $this->doQuery( $commentedSql );
746 wfDebug( "Failed\n" );
750 if ( false === $ret ) {
751 $this->reportQueryError( $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore );
754 if ( isset( $wgProfiler ) ) {
755 wfProfileOut( $queryProf );
756 wfProfileOut( $totalProf );
759 return $this->resultObject( $ret );
763 * @param $error String
764 * @param $errno Integer
766 * @param $fname String
767 * @param $tempIgnore Boolean
769 function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
770 # Ignore errors during error handling to avoid infinite recursion
771 $ignore = $this->ignoreErrors( true );
772 ++$this->mErrorCount;
774 if ( $ignore || $tempIgnore ) {
775 wfDebug( "SQL ERROR (ignored): $error\n" );
776 $this->ignoreErrors( $ignore );
778 $sql1line = str_replace( "\n", "\\n", $sql );
779 wfLogDBError( "$fname\t{$this->mServer}\t$errno\t$error\t$sql1line\n" );
780 wfDebug( "SQL ERROR: " . $error . "\n" );
781 throw new DBQueryError( $this, $error, $errno, $sql, $fname );
787 * Intended to be compatible with the PEAR::DB wrapper functions.
788 * http://pear.php.net/manual/en/package.database.db.intro-execute.php
790 * ? = scalar value, quoted as necessary
791 * ! = raw SQL bit (a function for instance)
792 * & = filename; reads the file and inserts as a blob
793 * (we don't use this though...)
795 function prepare( $sql, $func = 'DatabaseBase::prepare' ) {
796 /* MySQL doesn't support prepared statements (yet), so just
797 pack up the query for reference. We'll manually replace
799 return array( 'query' => $sql, 'func' => $func );
802 function freePrepared( $prepared ) {
803 /* No-op by default */
807 * Execute a prepared query with the various arguments
808 * @param $prepared String: the prepared sql
809 * @param $args Mixed: Either an array here, or put scalars as varargs
811 function execute( $prepared, $args = null ) {
812 if ( !is_array( $args ) ) {
814 $args = func_get_args();
815 array_shift( $args );
818 $sql = $this->fillPrepared( $prepared['query'], $args );
820 return $this->query( $sql, $prepared['func'] );
824 * Prepare & execute an SQL statement, quoting and inserting arguments
825 * in the appropriate places.
826 * @param $query String
829 function safeQuery( $query, $args = null ) {
830 $prepared = $this->prepare( $query, 'DatabaseBase::safeQuery' );
832 if ( !is_array( $args ) ) {
834 $args = func_get_args();
835 array_shift( $args );
838 $retval = $this->execute( $prepared, $args );
839 $this->freePrepared( $prepared );
845 * For faking prepared SQL statements on DBs that don't support
847 * @param $preparedQuery String: a 'preparable' SQL statement
848 * @param $args Array of arguments to fill it with
849 * @return string executable SQL
851 function fillPrepared( $preparedQuery, $args ) {
853 $this->preparedArgs =& $args;
855 return preg_replace_callback( '/(\\\\[?!&]|[?!&])/',
856 array( &$this, 'fillPreparedArg' ), $preparedQuery );
860 * preg_callback func for fillPrepared()
861 * The arguments should be in $this->preparedArgs and must not be touched
862 * while we're doing this.
864 * @param $matches Array
868 function fillPreparedArg( $matches ) {
869 switch( $matches[1] ) {
870 case '\\?': return '?';
871 case '\\!': return '!';
872 case '\\&': return '&';
875 list( /* $n */ , $arg ) = each( $this->preparedArgs );
877 switch( $matches[1] ) {
878 case '?': return $this->addQuotes( $arg );
879 case '!': return $arg;
881 # return $this->addQuotes( file_get_contents( $arg ) );
882 throw new DBUnexpectedError( $this, '& mode is not implemented. If it\'s really needed, uncomment the line above.' );
884 throw new DBUnexpectedError( $this, 'Received invalid match. This should never happen!' );
889 * Free a result object
890 * @param $res Mixed: A SQL result
892 function freeResult( $res ) {
893 # Stub. Might not really need to be overridden, since results should
894 # be freed by PHP when the variable goes out of scope anyway.
898 * Simple UPDATE wrapper
899 * Usually aborts on failure
900 * If errors are explicitly ignored, returns success
902 * This function exists for historical reasons, DatabaseBase::update() has a more standard
903 * calling convention and feature set
905 function set( $table, $var, $value, $cond, $fname = 'DatabaseBase::set' ) {
906 $table = $this->tableName( $table );
907 $sql = "UPDATE $table SET $var = '" .
908 $this->strencode( $value ) . "' WHERE ($cond)";
910 return (bool)$this->query( $sql, $fname );
914 * Simple SELECT wrapper, returns a single field, input must be encoded
915 * Usually aborts on failure
916 * If errors are explicitly ignored, returns FALSE on failure
918 function selectField( $table, $var, $cond = '', $fname = 'DatabaseBase::selectField', $options = array() ) {
919 if ( !is_array( $options ) ) {
920 $options = array( $options );
923 $options['LIMIT'] = 1;
925 $res = $this->select( $table, $var, $cond, $fname, $options );
927 if ( $res === false || !$this->numRows( $res ) ) {
931 $row = $this->fetchRow( $res );
933 if ( $row !== false ) {
934 return reset( $row );
941 * Returns an optional USE INDEX clause to go after the table, and a
942 * string to go at the end of the query
946 * @param $options Array: associative array of options to be turned into
947 * an SQL query, valid keys are listed in the function.
950 function makeSelectOptions( $options ) {
951 $preLimitTail = $postLimitTail = '';
954 $noKeyOptions = array();
956 foreach ( $options as $key => $option ) {
957 if ( is_numeric( $key ) ) {
958 $noKeyOptions[$option] = true;
962 if ( isset( $options['GROUP BY'] ) ) {
963 $preLimitTail .= " GROUP BY {$options['GROUP BY']}";
966 if ( isset( $options['HAVING'] ) ) {
967 $preLimitTail .= " HAVING {$options['HAVING']}";
970 if ( isset( $options['ORDER BY'] ) ) {
971 $preLimitTail .= " ORDER BY {$options['ORDER BY']}";
974 // if (isset($options['LIMIT'])) {
975 // $tailOpts .= $this->limitResult('', $options['LIMIT'],
976 // isset($options['OFFSET']) ? $options['OFFSET']
980 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
981 $postLimitTail .= ' FOR UPDATE';
984 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
985 $postLimitTail .= ' LOCK IN SHARE MODE';
988 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
989 $startOpts .= 'DISTINCT';
992 # Various MySQL extensions
993 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
994 $startOpts .= ' /*! STRAIGHT_JOIN */';
997 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
998 $startOpts .= ' HIGH_PRIORITY';
1001 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1002 $startOpts .= ' SQL_BIG_RESULT';
1005 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1006 $startOpts .= ' SQL_BUFFER_RESULT';
1009 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1010 $startOpts .= ' SQL_SMALL_RESULT';
1013 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1014 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1017 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1018 $startOpts .= ' SQL_CACHE';
1021 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1022 $startOpts .= ' SQL_NO_CACHE';
1025 if ( isset( $options['USE INDEX'] ) && ! is_array( $options['USE INDEX'] ) ) {
1026 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1031 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1037 * @param $table Mixed: Array or string, table name(s) (prefix auto-added)
1038 * @param $vars Mixed: Array or string, field name(s) to be retrieved
1039 * @param $conds Mixed: Array or string, condition(s) for WHERE
1040 * @param $fname String: Calling function name (use __METHOD__) for logs/profiling
1041 * @param $options Array: Associative array of options (e.g. array('GROUP BY' => 'page_title')),
1042 * see DatabaseBase::makeSelectOptions code for list of supported stuff
1043 * @param $join_conds Array: Associative array of table join conditions (optional)
1044 * (e.g. array( 'page' => array('LEFT JOIN','page_latest=rev_id') )
1045 * @return mixed Database result resource (feed to DatabaseBase::fetchObject or whatever), or false on failure
1047 function select( $table, $vars, $conds = '', $fname = 'DatabaseBase::select', $options = array(), $join_conds = array() ) {
1048 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1050 return $this->query( $sql, $fname );
1056 * @param $table Mixed: Array or string, table name(s) (prefix auto-added). Array keys are table aliases (optional)
1057 * @param $vars Mixed: Array or string, field name(s) to be retrieved
1058 * @param $conds Mixed: Array or string, condition(s) for WHERE
1059 * @param $fname String: Calling function name (use __METHOD__) for logs/profiling
1060 * @param $options Array: Associative array of options (e.g. array('GROUP BY' => 'page_title')),
1061 * see DatabaseBase::makeSelectOptions code for list of supported stuff
1062 * @param $join_conds Array: Associative array of table join conditions (optional)
1063 * (e.g. array( 'page' => array('LEFT JOIN','page_latest=rev_id') )
1064 * @return string, the SQL text
1066 function selectSQLText( $table, $vars, $conds = '', $fname = 'DatabaseBase::select', $options = array(), $join_conds = array() ) {
1067 if ( is_array( $vars ) ) {
1068 $vars = implode( ',', $vars );
1071 if ( !is_array( $options ) ) {
1072 $options = array( $options );
1075 if ( is_array( $table ) ) {
1076 if ( !empty( $join_conds ) || ( isset( $options['USE INDEX'] ) && is_array( @$options['USE INDEX'] ) ) ) {
1077 $from = ' FROM ' . $this->tableNamesWithUseIndexOrJOIN( $table, @$options['USE INDEX'], $join_conds );
1079 $from = ' FROM ' . implode( ',', $this->tableNamesWithAlias( $table ) );
1081 } elseif ( $table != '' ) {
1082 if ( $table { 0 } == ' ' ) {
1083 $from = ' FROM ' . $table;
1085 $from = ' FROM ' . $this->tableName( $table );
1091 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail ) = $this->makeSelectOptions( $options );
1093 if ( !empty( $conds ) ) {
1094 if ( is_array( $conds ) ) {
1095 $conds = $this->makeList( $conds, LIST_AND );
1097 $sql = "SELECT $startOpts $vars $from $useIndex WHERE $conds $preLimitTail";
1099 $sql = "SELECT $startOpts $vars $from $useIndex $preLimitTail";
1102 if ( isset( $options['LIMIT'] ) )
1103 $sql = $this->limitResult( $sql, $options['LIMIT'],
1104 isset( $options['OFFSET'] ) ? $options['OFFSET'] : false );
1105 $sql = "$sql $postLimitTail";
1107 if ( isset( $options['EXPLAIN'] ) ) {
1108 $sql = 'EXPLAIN ' . $sql;
1115 * Single row SELECT wrapper
1116 * Aborts or returns FALSE on error
1118 * @param $table String: table name
1119 * @param $vars String: the selected variables
1120 * @param $conds Array: a condition map, terms are ANDed together.
1121 * Items with numeric keys are taken to be literal conditions
1122 * Takes an array of selected variables, and a condition map, which is ANDed
1123 * e.g: selectRow( "page", array( "page_id" ), array( "page_namespace" =>
1124 * NS_MAIN, "page_title" => "Astronomy" ) ) would return an object where
1125 * $obj- >page_id is the ID of the Astronomy article
1126 * @param $fname String: Calling function name
1127 * @param $options Array
1128 * @param $join_conds Array
1130 * @todo migrate documentation to phpdocumentor format
1132 function selectRow( $table, $vars, $conds, $fname = 'DatabaseBase::selectRow', $options = array(), $join_conds = array() ) {
1133 $options['LIMIT'] = 1;
1134 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1136 if ( $res === false ) {
1140 if ( !$this->numRows( $res ) ) {
1144 $obj = $this->fetchObject( $res );
1150 * Estimate rows in dataset
1151 * Returns estimated count - not necessarily an accurate estimate across different databases,
1153 * Takes same arguments as DatabaseBase::select()
1155 * @param $table String: table name
1156 * @param $vars Array: unused
1157 * @param $conds Array: filters on the table
1158 * @param $fname String: function name for profiling
1159 * @param $options Array: options for select
1160 * @return Integer: row count
1162 public function estimateRowCount( $table, $vars = '*', $conds = '', $fname = 'DatabaseBase::estimateRowCount', $options = array() ) {
1164 $res = $this->select ( $table, 'COUNT(*) AS rowcount', $conds, $fname, $options );
1167 $row = $this->fetchRow( $res );
1168 $rows = ( isset( $row['rowcount'] ) ) ? $row['rowcount'] : 0;
1175 * Removes most variables from an SQL query and replaces them with X or N for numbers.
1176 * It's only slightly flawed. Don't use for anything important.
1178 * @param $sql String: A SQL Query
1180 static function generalizeSQL( $sql ) {
1181 # This does the same as the regexp below would do, but in such a way
1182 # as to avoid crashing php on some large strings.
1183 # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
1185 $sql = str_replace ( "\\\\", '', $sql );
1186 $sql = str_replace ( "\\'", '', $sql );
1187 $sql = str_replace ( "\\\"", '', $sql );
1188 $sql = preg_replace ( "/'.*'/s", "'X'", $sql );
1189 $sql = preg_replace ( '/".*"/s', "'X'", $sql );
1191 # All newlines, tabs, etc replaced by single space
1192 $sql = preg_replace ( '/\s+/', ' ', $sql );
1195 $sql = preg_replace ( '/-?[0-9]+/s', 'N', $sql );
1201 * Determines whether a field exists in a table
1203 * @param $table String: table name
1204 * @param $field String: filed to check on that table
1205 * @param $fname String: calling function name (optional)
1206 * @return Boolean: whether $table has filed $field
1208 function fieldExists( $table, $field, $fname = 'DatabaseBase::fieldExists' ) {
1209 $info = $this->fieldInfo( $table, $field );
1215 * Determines whether an index exists
1216 * Usually aborts on failure
1217 * If errors are explicitly ignored, returns NULL on failure
1219 function indexExists( $table, $index, $fname = 'DatabaseBase::indexExists' ) {
1220 $info = $this->indexInfo( $table, $index, $fname );
1221 if ( is_null( $info ) ) {
1224 return $info !== false;
1229 * Query whether a given table exists
1231 function tableExists( $table ) {
1232 $table = $this->tableName( $table );
1233 $old = $this->ignoreErrors( true );
1234 $res = $this->query( "SELECT 1 FROM $table LIMIT 1", __METHOD__ );
1235 $this->ignoreErrors( $old );
1241 * mysql_field_type() wrapper
1243 function fieldType( $res, $index ) {
1244 if ( $res instanceof ResultWrapper ) {
1245 $res = $res->result;
1248 return mysql_field_type( $res, $index );
1252 * Determines if a given index is unique
1254 function indexUnique( $table, $index ) {
1255 $indexInfo = $this->indexInfo( $table, $index );
1257 if ( !$indexInfo ) {
1261 return !$indexInfo[0]->Non_unique;
1265 * INSERT wrapper, inserts an array into a table
1267 * $a may be a single associative array, or an array of these with numeric keys, for
1270 * Usually aborts on failure
1271 * If errors are explicitly ignored, returns success
1273 * @param $table String: table name (prefix auto-added)
1274 * @param $a Array: Array of rows to insert
1275 * @param $fname String: Calling function name (use __METHOD__) for logs/profiling
1276 * @param $options Mixed: Associative array of options
1280 function insert( $table, $a, $fname = 'DatabaseBase::insert', $options = array() ) {
1281 # No rows to insert, easy just return now
1282 if ( !count( $a ) ) {
1286 $table = $this->tableName( $table );
1288 if ( !is_array( $options ) ) {
1289 $options = array( $options );
1292 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1294 $keys = array_keys( $a[0] );
1297 $keys = array_keys( $a );
1300 $sql = 'INSERT ' . implode( ' ', $options ) .
1301 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1305 foreach ( $a as $row ) {
1311 $sql .= '(' . $this->makeList( $row ) . ')';
1314 $sql .= '(' . $this->makeList( $a ) . ')';
1317 return (bool)$this->query( $sql, $fname );
1321 * Make UPDATE options for the DatabaseBase::update function
1324 * @param $options Array: The options passed to DatabaseBase::update
1327 function makeUpdateOptions( $options ) {
1328 if ( !is_array( $options ) ) {
1329 $options = array( $options );
1334 if ( in_array( 'LOW_PRIORITY', $options ) ) {
1335 $opts[] = $this->lowPriorityOption();
1338 if ( in_array( 'IGNORE', $options ) ) {
1342 return implode( ' ', $opts );
1346 * UPDATE wrapper, takes a condition array and a SET array
1348 * @param $table String: The table to UPDATE
1349 * @param $values Array: An array of values to SET
1350 * @param $conds Array: An array of conditions (WHERE). Use '*' to update all rows.
1351 * @param $fname String: The Class::Function calling this function
1353 * @param $options Array: An array of UPDATE options, can be one or
1354 * more of IGNORE, LOW_PRIORITY
1357 function update( $table, $values, $conds, $fname = 'DatabaseBase::update', $options = array() ) {
1358 $table = $this->tableName( $table );
1359 $opts = $this->makeUpdateOptions( $options );
1360 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, LIST_SET );
1362 if ( $conds != '*' ) {
1363 $sql .= " WHERE " . $this->makeList( $conds, LIST_AND );
1366 return $this->query( $sql, $fname );
1370 * Makes an encoded list of strings from an array
1372 * LIST_COMMA - comma separated, no field names
1373 * LIST_AND - ANDed WHERE clause (without the WHERE)
1374 * LIST_OR - ORed WHERE clause (without the WHERE)
1375 * LIST_SET - comma separated with field names, like a SET clause
1376 * LIST_NAMES - comma separated field names
1378 function makeList( $a, $mode = LIST_COMMA ) {
1379 if ( !is_array( $a ) ) {
1380 throw new DBUnexpectedError( $this, 'DatabaseBase::makeList called with incorrect parameters' );
1386 foreach ( $a as $field => $value ) {
1388 if ( $mode == LIST_AND ) {
1390 } elseif ( $mode == LIST_OR ) {
1399 if ( ( $mode == LIST_AND || $mode == LIST_OR ) && is_numeric( $field ) ) {
1400 $list .= "($value)";
1401 } elseif ( ( $mode == LIST_SET ) && is_numeric( $field ) ) {
1403 } elseif ( ( $mode == LIST_AND || $mode == LIST_OR ) && is_array( $value ) ) {
1404 if ( count( $value ) == 0 ) {
1405 throw new MWException( __METHOD__ . ': empty input' );
1406 } elseif ( count( $value ) == 1 ) {
1407 // Special-case single values, as IN isn't terribly efficient
1408 // Don't necessarily assume the single key is 0; we don't
1409 // enforce linear numeric ordering on other arrays here.
1410 $value = array_values( $value );
1411 $list .= $field . " = " . $this->addQuotes( $value[0] );
1413 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
1415 } elseif ( $value === null ) {
1416 if ( $mode == LIST_AND || $mode == LIST_OR ) {
1417 $list .= "$field IS ";
1418 } elseif ( $mode == LIST_SET ) {
1419 $list .= "$field = ";
1423 if ( $mode == LIST_AND || $mode == LIST_OR || $mode == LIST_SET ) {
1424 $list .= "$field = ";
1426 $list .= $mode == LIST_NAMES ? $value : $this->addQuotes( $value );
1434 * Build a partial where clause from a 2-d array such as used for LinkBatch.
1435 * The keys on each level may be either integers or strings.
1437 * @param $data Array: organized as 2-d array(baseKeyVal => array(subKeyVal => <ignored>, ...), ...)
1438 * @param $baseKey String: field name to match the base-level keys to (eg 'pl_namespace')
1439 * @param $subKey String: field name to match the sub-level keys to (eg 'pl_title')
1440 * @return Mixed: string SQL fragment, or false if no items in array.
1442 function makeWhereFrom2d( $data, $baseKey, $subKey ) {
1445 foreach ( $data as $base => $sub ) {
1446 if ( count( $sub ) ) {
1447 $conds[] = $this->makeList(
1448 array( $baseKey => $base, $subKey => array_keys( $sub ) ),
1454 return $this->makeList( $conds, LIST_OR );
1456 // Nothing to search for...
1462 * Bitwise operations
1465 function bitNot( $field ) {
1469 function bitAnd( $fieldLeft, $fieldRight ) {
1470 return "($fieldLeft & $fieldRight)";
1473 function bitOr( $fieldLeft, $fieldRight ) {
1474 return "($fieldLeft | $fieldRight)";
1478 * Change the current database
1480 * @todo Explain what exactly will fail if this is not overridden.
1481 * @return bool Success or failure
1483 function selectDB( $db ) {
1484 # Stub. Shouldn't cause serious problems if it's not overridden, but
1485 # if your database engine supports a concept similar to MySQL's
1486 # databases you may as well.
1491 * Get the current DB name
1493 function getDBname() {
1494 return $this->mDBname;
1498 * Get the server hostname or IP address
1500 function getServer() {
1501 return $this->mServer;
1505 * Format a table name ready for use in constructing an SQL query
1507 * This does two important things: it quotes the table names to clean them up,
1508 * and it adds a table prefix if only given a table name with no quotes.
1510 * All functions of this object which require a table name call this function
1511 * themselves. Pass the canonical name to such functions. This is only needed
1512 * when calling query() directly.
1514 * @param $name String: database table name
1515 * @return String: full database name
1517 function tableName( $name ) {
1518 global $wgSharedDB, $wgSharedPrefix, $wgSharedTables;
1519 # Skip the entire process when we have a string quoted on both ends.
1520 # Note that we check the end so that we will still quote any use of
1521 # use of `database`.table. But won't break things if someone wants
1522 # to query a database table with a dot in the name.
1523 if ( $name[0] == '`' && substr( $name, -1, 1 ) == '`' ) {
1527 # Lets test for any bits of text that should never show up in a table
1528 # name. Basically anything like JOIN or ON which are actually part of
1529 # SQL queries, but may end up inside of the table value to combine
1530 # sql. Such as how the API is doing.
1531 # Note that we use a whitespace test rather than a \b test to avoid
1532 # any remote case where a word like on may be inside of a table name
1533 # surrounded by symbols which may be considered word breaks.
1534 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
1538 # Split database and table into proper variables.
1539 # We reverse the explode so that database.table and table both output
1540 # the correct table.
1541 $dbDetails = array_reverse( explode( '.', $name, 2 ) );
1542 if ( isset( $dbDetails[1] ) ) {
1543 @list( $table, $database ) = $dbDetails;
1545 @list( $table ) = $dbDetails;
1547 $prefix = $this->mTablePrefix; # Default prefix
1549 # A database name has been specified in input. Quote the table name
1550 # because we don't want any prefixes added.
1551 if ( isset( $database ) ) {
1552 $table = ( $table[0] == '`' ? $table : "`{$table}`" );
1555 # Note that we use the long format because php will complain in in_array if
1556 # the input is not an array, and will complain in is_array if it is not set.
1557 if ( !isset( $database ) # Don't use shared database if pre selected.
1558 && isset( $wgSharedDB ) # We have a shared database
1559 && $table[0] != '`' # Paranoia check to prevent shared tables listing '`table`'
1560 && isset( $wgSharedTables )
1561 && is_array( $wgSharedTables )
1562 && in_array( $table, $wgSharedTables ) ) { # A shared table is selected
1563 $database = $wgSharedDB;
1564 $prefix = isset( $wgSharedPrefix ) ? $wgSharedPrefix : $prefix;
1567 # Quote the $database and $table and apply the prefix if not quoted.
1568 if ( isset( $database ) ) {
1569 $database = ( $database[0] == '`' ? $database : "`{$database}`" );
1571 $table = ( $table[0] == '`' ? $table : "`{$prefix}{$table}`" );
1573 # Merge our database and table into our final table name.
1574 $tableName = ( isset( $database ) ? "{$database}.{$table}" : "{$table}" );
1580 * Fetch a number of table names into an array
1581 * This is handy when you need to construct SQL for joins
1584 * extract($dbr->tableNames('user','watchlist'));
1585 * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1586 * WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1588 public function tableNames() {
1589 $inArray = func_get_args();
1592 foreach ( $inArray as $name ) {
1593 $retVal[$name] = $this->tableName( $name );
1600 * Fetch a number of table names into an zero-indexed numerical array
1601 * This is handy when you need to construct SQL for joins
1604 * list( $user, $watchlist ) = $dbr->tableNamesN('user','watchlist');
1605 * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1606 * WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1608 public function tableNamesN() {
1609 $inArray = func_get_args();
1612 foreach ( $inArray as $name ) {
1613 $retVal[] = $this->tableName( $name );
1620 * Get an aliased table name
1621 * e.g. tableName AS newTableName
1623 * @param $name string Table name, see tableName()
1624 * @param $alias string Alias (optional)
1625 * @return string SQL name for aliased table. Will not alias a table to its own name
1627 public function tableNameWithAlias( $name, $alias = false ) {
1628 if ( !$alias || $alias == $name ) {
1629 return $this->tableName( $name );
1631 return $this->tableName( $name ) . ' ' . $this->addIdentifierQuotes( $alias );
1636 * Gets an array of aliased table names
1638 * @param $tables array( [alias] => table )
1639 * @return array of strings, see tableNameWithAlias()
1641 public function tableNamesWithAlias( $tables ) {
1643 foreach ( $tables as $alias => $table ) {
1644 if ( is_numeric( $alias ) ) {
1647 $retval[] = $this->tableNameWithAlias( $table, $alias );
1655 function tableNamesWithUseIndexOrJOIN( $tables, $use_index = array(), $join_conds = array() ) {
1658 $use_index_safe = is_array( $use_index ) ? $use_index : array();
1659 $join_conds_safe = is_array( $join_conds ) ? $join_conds : array();
1661 foreach ( $tables as $alias => $table ) {
1662 if ( !is_string( $alias ) ) {
1663 // No alias? Set it equal to the table name
1666 // Is there a JOIN and INDEX clause for this table?
1667 if ( isset( $join_conds_safe[$alias] ) && isset( $use_index_safe[$alias] ) ) {
1668 $tableClause = $join_conds_safe[$alias][0] . ' ' . $this->tableNameWithAlias( $table, $alias );
1669 $tableClause .= ' ' . $this->useIndexClause( implode( ',', (array)$use_index_safe[$alias] ) );
1670 $on = $this->makeList( (array)$join_conds_safe[$alias][1], LIST_AND );
1672 $tableClause .= ' ON (' . $on . ')';
1675 $retJOIN[] = $tableClause;
1676 // Is there an INDEX clause?
1677 } else if ( isset( $use_index_safe[$alias] ) ) {
1678 $tableClause = $this->tableNameWithAlias( $table, $alias );
1679 $tableClause .= ' ' . $this->useIndexClause( implode( ',', (array)$use_index_safe[$alias] ) );
1680 $ret[] = $tableClause;
1681 // Is there a JOIN clause?
1682 } else if ( isset( $join_conds_safe[$alias] ) ) {
1683 $tableClause = $join_conds_safe[$alias][0] . ' ' . $this->tableNameWithAlias( $table, $alias );
1684 $on = $this->makeList( (array)$join_conds_safe[$alias][1], LIST_AND );
1686 $tableClause .= ' ON (' . $on . ')';
1689 $retJOIN[] = $tableClause;
1691 $tableClause = $this->tableNameWithAlias( $table, $alias );
1692 $ret[] = $tableClause;
1696 // We can't separate explicit JOIN clauses with ',', use ' ' for those
1697 $straightJoins = !empty( $ret ) ? implode( ',', $ret ) : "";
1698 $otherJoins = !empty( $retJOIN ) ? implode( ' ', $retJOIN ) : "";
1700 // Compile our final table clause
1701 return implode( ' ', array( $straightJoins, $otherJoins ) );
1705 * Get the name of an index in a given table
1707 function indexName( $index ) {
1708 // Backwards-compatibility hack
1710 'ar_usertext_timestamp' => 'usertext_timestamp',
1711 'un_user_id' => 'user_id',
1712 'un_user_ip' => 'user_ip',
1715 if ( isset( $renamed[$index] ) ) {
1716 return $renamed[$index];
1723 * If it's a string, adds quotes and backslashes
1724 * Otherwise returns as-is
1726 function addQuotes( $s ) {
1727 if ( $s === null ) {
1730 # This will also quote numeric values. This should be harmless,
1731 # and protects against weird problems that occur when they really
1732 # _are_ strings such as article titles and string->number->string
1733 # conversion is not 1:1.
1734 return "'" . $this->strencode( $s ) . "'";
1739 * Quotes an identifier using `backticks` or "double quotes" depending on the database type.
1740 * MySQL uses `backticks` while basically everything else uses double quotes.
1741 * Since MySQL is the odd one out here the double quotes are our generic
1742 * and we implement backticks in DatabaseMysql.
1744 public function addIdentifierQuotes( $s ) {
1745 return '"' . str_replace( '"', '""', $s ) . '"';
1749 * Backwards compatibility, identifier quoting originated in DatabasePostgres
1750 * which used quote_ident which does not follow our naming conventions
1751 * was renamed to addIdentifierQuotes.
1752 * @deprecated use addIdentifierQuotes
1754 function quote_ident( $s ) {
1755 wfDeprecated( __METHOD__ );
1756 return $this->addIdentifierQuotes( $s );
1760 * Escape string for safe LIKE usage.
1761 * WARNING: you should almost never use this function directly,
1762 * instead use buildLike() that escapes everything automatically
1763 * Deprecated in 1.17, warnings in 1.17, removed in ???
1765 public function escapeLike( $s ) {
1766 wfDeprecated( __METHOD__ );
1767 return $this->escapeLikeInternal( $s );
1770 protected function escapeLikeInternal( $s ) {
1771 $s = str_replace( '\\', '\\\\', $s );
1772 $s = $this->strencode( $s );
1773 $s = str_replace( array( '%', '_' ), array( '\%', '\_' ), $s );
1779 * LIKE statement wrapper, receives a variable-length argument list with parts of pattern to match
1780 * containing either string literals that will be escaped or tokens returned by anyChar() or anyString().
1781 * Alternatively, the function could be provided with an array of aforementioned parameters.
1783 * Example: $dbr->buildLike( 'My_page_title/', $dbr->anyString() ) returns a LIKE clause that searches
1784 * for subpages of 'My page title'.
1785 * Alternatively: $pattern = array( 'My_page_title/', $dbr->anyString() ); $query .= $dbr->buildLike( $pattern );
1788 * @return String: fully built LIKE statement
1790 function buildLike() {
1791 $params = func_get_args();
1793 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
1794 $params = $params[0];
1799 foreach ( $params as $value ) {
1800 if ( $value instanceof LikeMatch ) {
1801 $s .= $value->toString();
1803 $s .= $this->escapeLikeInternal( $value );
1807 return " LIKE '" . $s . "' ";
1811 * Returns a token for buildLike() that denotes a '_' to be used in a LIKE query
1813 function anyChar() {
1814 return new LikeMatch( '_' );
1818 * Returns a token for buildLike() that denotes a '%' to be used in a LIKE query
1820 function anyString() {
1821 return new LikeMatch( '%' );
1825 * Returns an appropriately quoted sequence value for inserting a new row.
1826 * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL
1827 * subclass will return an integer, and save the value for insertId()
1829 function nextSequenceValue( $seqName ) {
1834 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
1835 * is only needed because a) MySQL must be as efficient as possible due to
1836 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
1837 * which index to pick. Anyway, other databases might have different
1838 * indexes on a given table. So don't bother overriding this unless you're
1841 function useIndexClause( $index ) {
1846 * REPLACE query wrapper
1847 * PostgreSQL simulates this with a DELETE followed by INSERT
1848 * $row is the row to insert, an associative array
1849 * $uniqueIndexes is an array of indexes. Each element may be either a
1850 * field name or an array of field names
1852 * It may be more efficient to leave off unique indexes which are unlikely to collide.
1853 * However if you do this, you run the risk of encountering errors which wouldn't have
1856 * @param $table String: The table to replace the row(s) in.
1857 * @param $uniqueIndexes Array: An associative array of indexes
1858 * @param $rows Array: Array of rows to replace
1859 * @param $fname String: Calling function name (use __METHOD__) for logs/profiling
1861 function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseBase::replace' ) {
1862 $table = $this->tableName( $table );
1865 if ( !is_array( reset( $rows ) ) ) {
1866 $rows = array( $rows );
1869 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
1872 foreach ( $rows as $row ) {
1879 $sql .= '(' . $this->makeList( $row ) . ')';
1882 return $this->query( $sql, $fname );
1886 * DELETE where the condition is a join
1887 * MySQL does this with a multi-table DELETE syntax, PostgreSQL does it with sub-selects
1889 * For safety, an empty $conds will not delete everything. If you want to delete all rows where the
1890 * join condition matches, set $conds='*'
1892 * DO NOT put the join condition in $conds
1894 * @param $delTable String: The table to delete from.
1895 * @param $joinTable String: The other table.
1896 * @param $delVar String: The variable to join on, in the first table.
1897 * @param $joinVar String: The variable to join on, in the second table.
1898 * @param $conds Array: Condition array of field names mapped to variables, ANDed together in the WHERE clause
1899 * @param $fname String: Calling function name (use __METHOD__) for logs/profiling
1901 function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'DatabaseBase::deleteJoin' ) {
1903 throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
1906 $delTable = $this->tableName( $delTable );
1907 $joinTable = $this->tableName( $joinTable );
1908 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1910 if ( $conds != '*' ) {
1911 $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
1914 return $this->query( $sql, $fname );
1918 * Returns the size of a text field, or -1 for "unlimited"
1920 function textFieldSize( $table, $field ) {
1921 $table = $this->tableName( $table );
1922 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
1923 $res = $this->query( $sql, 'DatabaseBase::textFieldSize' );
1924 $row = $this->fetchObject( $res );
1928 if ( preg_match( '/\((.*)\)/', $row->Type, $m ) ) {
1938 * A string to insert into queries to show that they're low-priority, like
1939 * MySQL's LOW_PRIORITY. If no such feature exists, return an empty
1940 * string and nothing bad should happen.
1942 * @return string Returns the text of the low priority option if it is supported, or a blank string otherwise
1944 function lowPriorityOption() {
1949 * DELETE query wrapper
1951 * Use $conds == "*" to delete all rows
1953 function delete( $table, $conds, $fname = 'DatabaseBase::delete' ) {
1955 throw new DBUnexpectedError( $this, 'DatabaseBase::delete() called with no conditions' );
1958 $table = $this->tableName( $table );
1959 $sql = "DELETE FROM $table";
1961 if ( $conds != '*' ) {
1962 $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1965 return $this->query( $sql, $fname );
1969 * INSERT SELECT wrapper
1970 * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
1971 * Source items may be literals rather than field names, but strings should be quoted with DatabaseBase::addQuotes()
1972 * $conds may be "*" to copy the whole table
1973 * srcTable may be an array of tables.
1975 function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'DatabaseBase::insertSelect',
1976 $insertOptions = array(), $selectOptions = array() )
1978 $destTable = $this->tableName( $destTable );
1980 if ( is_array( $insertOptions ) ) {
1981 $insertOptions = implode( ' ', $insertOptions );
1984 if ( !is_array( $selectOptions ) ) {
1985 $selectOptions = array( $selectOptions );
1988 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
1990 if ( is_array( $srcTable ) ) {
1991 $srcTable = implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
1993 $srcTable = $this->tableName( $srcTable );
1996 $sql = "INSERT $insertOptions INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
1997 " SELECT $startOpts " . implode( ',', $varMap ) .
1998 " FROM $srcTable $useIndex ";
2000 if ( $conds != '*' ) {
2001 $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
2004 $sql .= " $tailOpts";
2006 return $this->query( $sql, $fname );
2010 * Construct a LIMIT query with optional offset. This is used for query
2011 * pages. The SQL should be adjusted so that only the first $limit rows
2012 * are returned. If $offset is provided as well, then the first $offset
2013 * rows should be discarded, and the next $limit rows should be returned.
2014 * If the result of the query is not ordered, then the rows to be returned
2015 * are theoretically arbitrary.
2017 * $sql is expected to be a SELECT, if that makes a difference. For
2018 * UPDATE, limitResultForUpdate should be used.
2020 * The version provided by default works in MySQL and SQLite. It will very
2021 * likely need to be overridden for most other DBMSes.
2023 * @param $sql String: SQL query we will append the limit too
2024 * @param $limit Integer: the SQL limit
2025 * @param $offset Integer the SQL offset (default false)
2027 function limitResult( $sql, $limit, $offset = false ) {
2028 if ( !is_numeric( $limit ) ) {
2029 throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" );
2032 return "$sql LIMIT "
2033 . ( ( is_numeric( $offset ) && $offset != 0 ) ? "{$offset}," : "" )
2037 function limitResultForUpdate( $sql, $num ) {
2038 return $this->limitResult( $sql, $num, 0 );
2042 * Returns true if current database backend supports ORDER BY or LIMIT for separate subqueries
2043 * within the UNION construct.
2046 function unionSupportsOrderAndLimit() {
2047 return true; // True for almost every DB supported
2051 * Construct a UNION query
2052 * This is used for providing overload point for other DB abstractions
2053 * not compatible with the MySQL syntax.
2054 * @param $sqls Array: SQL statements to combine
2055 * @param $all Boolean: use UNION ALL
2056 * @return String: SQL fragment
2058 function unionQueries( $sqls, $all ) {
2059 $glue = $all ? ') UNION ALL (' : ') UNION (';
2060 return '(' . implode( $glue, $sqls ) . ')';
2064 * Returns an SQL expression for a simple conditional. This doesn't need
2065 * to be overridden unless CASE isn't supported in your DBMS.
2067 * @param $cond String: SQL expression which will result in a boolean value
2068 * @param $trueVal String: SQL expression to return if true
2069 * @param $falseVal String: SQL expression to return if false
2070 * @return String: SQL fragment
2072 function conditional( $cond, $trueVal, $falseVal ) {
2073 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
2077 * Returns a comand for str_replace function in SQL query.
2078 * Uses REPLACE() in MySQL
2080 * @param $orig String: column to modify
2081 * @param $old String: column to seek
2082 * @param $new String: column to replace with
2084 function strreplace( $orig, $old, $new ) {
2085 return "REPLACE({$orig}, {$old}, {$new})";
2089 * Convert a field to an unix timestamp
2091 * @param $field String: field name
2092 * @return String: SQL statement
2094 public function unixTimestamp( $field ) {
2095 return "EXTRACT(epoch FROM $field)";
2099 * Determines if the last failure was due to a deadlock
2102 function wasDeadlock() {
2107 * Determines if the last query error was something that should be dealt
2108 * with by pinging the connection and reissuing the query.
2111 function wasErrorReissuable() {
2116 * Determines if the last failure was due to the database being read-only.
2119 function wasReadOnlyError() {
2124 * Perform a deadlock-prone transaction.
2126 * This function invokes a callback function to perform a set of write
2127 * queries. If a deadlock occurs during the processing, the transaction
2128 * will be rolled back and the callback function will be called again.
2131 * $dbw->deadlockLoop( callback, ... );
2133 * Extra arguments are passed through to the specified callback function.
2135 * Returns whatever the callback function returned on its successful,
2136 * iteration, or false on error, for example if the retry limit was
2139 function deadlockLoop() {
2140 $myFname = 'DatabaseBase::deadlockLoop';
2143 $args = func_get_args();
2144 $function = array_shift( $args );
2145 $oldIgnore = $this->ignoreErrors( true );
2146 $tries = DEADLOCK_TRIES;
2148 if ( is_array( $function ) ) {
2149 $fname = $function[0];
2155 $retVal = call_user_func_array( $function, $args );
2156 $error = $this->lastError();
2157 $errno = $this->lastErrno();
2158 $sql = $this->lastQuery();
2161 if ( $this->wasDeadlock() ) {
2163 usleep( mt_rand( DEADLOCK_DELAY_MIN, DEADLOCK_DELAY_MAX ) );
2165 $this->reportQueryError( $error, $errno, $sql, $fname );
2168 } while ( $this->wasDeadlock() && --$tries > 0 );
2170 $this->ignoreErrors( $oldIgnore );
2172 if ( $tries <= 0 ) {
2173 $this->rollback( $myFname );
2174 $this->reportQueryError( $error, $errno, $sql, $fname );
2177 $this->commit( $myFname );
2183 * Do a SELECT MASTER_POS_WAIT()
2185 * @param $pos MySQLMasterPos object
2186 * @param $timeout Integer: the maximum number of seconds to wait for synchronisation
2188 function masterPosWait( MySQLMasterPos $pos, $timeout ) {
2189 $fname = 'DatabaseBase::masterPosWait';
2190 wfProfileIn( $fname );
2192 # Commit any open transactions
2193 if ( $this->mTrxLevel ) {
2197 if ( !is_null( $this->mFakeSlaveLag ) ) {
2198 $wait = intval( ( $pos->pos - microtime( true ) + $this->mFakeSlaveLag ) * 1e6 );
2200 if ( $wait > $timeout * 1e6 ) {
2201 wfDebug( "Fake slave timed out waiting for $pos ($wait us)\n" );
2202 wfProfileOut( $fname );
2204 } elseif ( $wait > 0 ) {
2205 wfDebug( "Fake slave waiting $wait us\n" );
2207 wfProfileOut( $fname );
2210 wfDebug( "Fake slave up to date ($wait us)\n" );
2211 wfProfileOut( $fname );
2216 # Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
2217 $encFile = $this->addQuotes( $pos->file );
2218 $encPos = intval( $pos->pos );
2219 $sql = "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)";
2220 $res = $this->doQuery( $sql );
2222 if ( $res && $row = $this->fetchRow( $res ) ) {
2223 wfProfileOut( $fname );
2226 wfProfileOut( $fname );
2232 * Get the position of the master from SHOW SLAVE STATUS
2234 function getSlavePos() {
2235 if ( !is_null( $this->mFakeSlaveLag ) ) {
2236 $pos = new MySQLMasterPos( 'fake', microtime( true ) - $this->mFakeSlaveLag );
2237 wfDebug( __METHOD__ . ": fake slave pos = $pos\n" );
2241 $res = $this->query( 'SHOW SLAVE STATUS', 'DatabaseBase::getSlavePos' );
2242 $row = $this->fetchObject( $res );
2245 $pos = isset( $row->Exec_master_log_pos ) ? $row->Exec_master_log_pos : $row->Exec_Master_Log_Pos;
2246 return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos );
2253 * Get the position of the master from SHOW MASTER STATUS
2255 function getMasterPos() {
2256 if ( $this->mFakeMaster ) {
2257 return new MySQLMasterPos( 'fake', microtime( true ) );
2260 $res = $this->query( 'SHOW MASTER STATUS', 'DatabaseBase::getMasterPos' );
2261 $row = $this->fetchObject( $res );
2264 return new MySQLMasterPos( $row->File, $row->Position );
2271 * Begin a transaction, committing any previously open transaction
2273 function begin( $fname = 'DatabaseBase::begin' ) {
2274 $this->query( 'BEGIN', $fname );
2275 $this->mTrxLevel = 1;
2281 function commit( $fname = 'DatabaseBase::commit' ) {
2282 if ( $this->mTrxLevel ) {
2283 $this->query( 'COMMIT', $fname );
2284 $this->mTrxLevel = 0;
2289 * Rollback a transaction.
2290 * No-op on non-transactional databases.
2292 function rollback( $fname = 'DatabaseBase::rollback' ) {
2293 if ( $this->mTrxLevel ) {
2294 $this->query( 'ROLLBACK', $fname, true );
2295 $this->mTrxLevel = 0;
2300 * Begin a transaction, committing any previously open transaction
2301 * @deprecated use begin()
2303 function immediateBegin( $fname = 'DatabaseBase::immediateBegin' ) {
2304 wfDeprecated( __METHOD__ );
2309 * Commit transaction, if one is open
2310 * @deprecated use commit()
2312 function immediateCommit( $fname = 'DatabaseBase::immediateCommit' ) {
2313 wfDeprecated( __METHOD__ );
2318 * Creates a new table with structure copied from existing table
2319 * Note that unlike most database abstraction functions, this function does not
2320 * automatically append database prefix, because it works at a lower
2321 * abstraction level.
2323 * @param $oldName String: name of table whose structure should be copied
2324 * @param $newName String: name of table to be created
2325 * @param $temporary Boolean: whether the new table should be temporary
2326 * @param $fname String: calling function name
2327 * @return Boolean: true if operation was successful
2329 function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabaseBase::duplicateTableStructure' ) {
2330 throw new MWException( 'DatabaseBase::duplicateTableStructure is not implemented in descendant class' );
2334 * Return MW-style timestamp used for MySQL schema
2336 function timestamp( $ts = 0 ) {
2337 return wfTimestamp( TS_MW, $ts );
2341 * Local database timestamp format or null
2343 function timestampOrNull( $ts = null ) {
2344 if ( is_null( $ts ) ) {
2347 return $this->timestamp( $ts );
2354 function resultObject( $result ) {
2355 if ( empty( $result ) ) {
2357 } elseif ( $result instanceof ResultWrapper ) {
2359 } elseif ( $result === true ) {
2360 // Successful write query
2363 return new ResultWrapper( $this, $result );
2368 * Return aggregated value alias
2370 function aggregateValue ( $valuedata, $valuename = 'value' ) {
2375 * Ping the server and try to reconnect if it there is no connection
2377 * @return bool Success or failure
2380 # Stub. Not essential to override.
2386 * Currently supported only by MySQL
2387 * @return Database replication lag in seconds
2390 return intval( $this->mFakeSlaveLag );
2394 * Get status information from SHOW STATUS in an associative array
2396 function getStatus( $which = "%" ) {
2397 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
2400 foreach ( $res as $row ) {
2401 $status[$row->Variable_name] = $row->Value;
2408 * Return the maximum number of items allowed in a list, or 0 for unlimited.
2410 function maxListLen() {
2414 function encodeBlob( $b ) {
2418 function decodeBlob( $b ) {
2423 * Override database's default connection timeout. May be useful for very
2424 * long batch queries such as full-wiki dumps, where a single query reads
2425 * out over hours or days. May or may not be necessary for non-MySQL
2426 * databases. For most purposes, leaving it as a no-op should be fine.
2428 * @param $timeout Integer in seconds
2430 public function setTimeout( $timeout ) {}
2433 * Read and execute SQL commands from a file.
2434 * Returns true on success, error string or exception on failure (depending on object's error ignore settings)
2435 * @param $filename String: File name to open
2436 * @param $lineCallback Callback: Optional function called before reading each line
2437 * @param $resultCallback Callback: Optional function called for each MySQL result
2438 * @param $fname String: Calling function name or false if name should be generated dynamically
2441 function sourceFile( $filename, $lineCallback = false, $resultCallback = false, $fname = false ) {
2442 $fp = fopen( $filename, 'r' );
2444 if ( false === $fp ) {
2445 if ( !defined( "MEDIAWIKI_INSTALL" ) )
2446 throw new MWException( "Could not open \"{$filename}\".\n" );
2448 return "Could not open \"{$filename}\".\n";
2452 $fname = __METHOD__ . "( $filename )";
2456 $error = $this->sourceStream( $fp, $lineCallback, $resultCallback, $fname );
2458 catch ( MWException $e ) {
2459 if ( defined( "MEDIAWIKI_INSTALL" ) ) {
2460 $error = $e->getMessage();
2473 * Get the full path of a patch file. Originally based on archive()
2474 * from updaters.inc. Keep in mind this always returns a patch, as
2475 * it fails back to MySQL if no DB-specific patch can be found
2477 * @param $patch String The name of the patch, like patch-something.sql
2478 * @return String Full path to patch file
2480 public function patchPath( $patch ) {
2483 $dbType = $this->getType();
2484 if ( file_exists( "$IP/maintenance/$dbType/archives/$patch" ) ) {
2485 return "$IP/maintenance/$dbType/archives/$patch";
2487 return "$IP/maintenance/archives/$patch";
2492 * Set variables to be used in sourceFile/sourceStream, in preference to the
2493 * ones in $GLOBALS. If an array is set here, $GLOBALS will not be used at
2494 * all. If it's set to false, $GLOBALS will be used.
2496 * @param $vars False, or array mapping variable name to value.
2498 function setSchemaVars( $vars ) {
2499 $this->mSchemaVars = $vars;
2503 * Read and execute commands from an open file handle
2504 * Returns true on success, error string or exception on failure (depending on object's error ignore settings)
2505 * @param $fp String: File handle
2506 * @param $lineCallback Callback: Optional function called before reading each line
2507 * @param $resultCallback Callback: Optional function called for each MySQL result
2508 * @param $fname String: Calling function name
2510 function sourceStream( $fp, $lineCallback = false, $resultCallback = false, $fname = 'DatabaseBase::sourceStream' ) {
2513 $dollarquote = false;
2515 while ( ! feof( $fp ) ) {
2516 if ( $lineCallback ) {
2517 call_user_func( $lineCallback );
2520 $line = trim( fgets( $fp, 1024 ) );
2521 $sl = strlen( $line ) - 1;
2527 if ( '-' == $line { 0 } && '-' == $line { 1 } ) {
2531 # # Allow dollar quoting for function declarations
2532 if ( substr( $line, 0, 4 ) == '$mw$' ) {
2533 if ( $dollarquote ) {
2534 $dollarquote = false;
2538 $dollarquote = true;
2541 else if ( !$dollarquote ) {
2542 if ( ';' == $line { $sl } && ( $sl < 2 || ';' != $line { $sl - 1 } ) ) {
2544 $line = substr( $line, 0, $sl );
2555 $cmd = str_replace( ';;', ";", $cmd );
2556 $cmd = $this->replaceVars( $cmd );
2557 $res = $this->query( $cmd, $fname );
2559 if ( $resultCallback ) {
2560 call_user_func( $resultCallback, $res, $this );
2563 if ( false === $res ) {
2564 $err = $this->lastError();
2565 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
2577 * Database independent variable replacement, replaces a set of variables
2578 * in a sql statement with their contents as given by $this->getSchemaVars().
2579 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables
2581 * '{$var}' should be used for text and is passed through the database's addQuotes method
2582 * `{$var}` should be used for identifiers (eg: table and database names), it is passed through
2583 * the database's addIdentifierQuotes method which can be overridden if the database
2584 * uses something other than backticks.
2585 * / *$var* / is just encoded, besides traditional dbprefix and tableoptions it's use should be avoided
2587 * @param $ins String: SQL statement to replace variables in
2588 * @return String The new SQL statement with variables replaced
2590 protected function replaceSchemaVars( $ins ) {
2591 $vars = $this->getSchemaVars();
2592 foreach ( $vars as $var => $value ) {
2594 $ins = str_replace( '\'{$' . $var . '}\'', $this->addQuotes( $value ), $ins );
2596 $ins = str_replace( '`{$' . $var . '}`', $this->addIdentifierQuotes( $value ), $ins );
2598 $ins = str_replace( '/*$' . $var . '*/', $this->strencode( $value ) , $ins );
2604 * Replace variables in sourced SQL
2606 protected function replaceVars( $ins ) {
2607 $ins = $this->replaceSchemaVars( $ins );
2610 $ins = preg_replace_callback( '!/\*(?:\$wgDBprefix|_)\*/([a-zA-Z_0-9]*)!',
2611 array( $this, 'tableNameCallback' ), $ins );
2614 $ins = preg_replace_callback( '!/\*i\*/([a-zA-Z_0-9]*)!',
2615 array( $this, 'indexNameCallback' ), $ins );
2621 * Get schema variables. If none have been set via setSchemaVars(), then
2622 * use some defaults from the current object.
2624 protected function getSchemaVars() {
2625 if ( $this->mSchemaVars ) {
2626 return $this->mSchemaVars;
2628 return $this->getDefaultSchemaVars();
2633 * Get schema variables to use if none have been set via setSchemaVars().
2634 * Override this in derived classes to provide variables for tables.sql
2635 * and SQL patch files.
2637 protected function getDefaultSchemaVars() {
2642 * Table name callback
2645 protected function tableNameCallback( $matches ) {
2646 return $this->tableName( $matches[1] );
2650 * Index name callback
2652 protected function indexNameCallback( $matches ) {
2653 return $this->indexName( $matches[1] );
2657 * Build a concatenation list to feed into a SQL query
2658 * @param $stringList Array: list of raw SQL expressions; caller is responsible for any quoting
2661 function buildConcat( $stringList ) {
2662 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2666 * Acquire a named lock
2668 * Abstracted from Filestore::lock() so child classes can implement for
2671 * @param $lockName String: name of lock to aquire
2672 * @param $method String: name of method calling us
2673 * @param $timeout Integer: timeout
2676 public function lock( $lockName, $method, $timeout = 5 ) {
2683 * @param $lockName String: Name of lock to release
2684 * @param $method String: Name of method calling us
2686 * @return Returns 1 if the lock was released, 0 if the lock was not established
2687 * by this thread (in which case the lock is not released), and NULL if the named
2688 * lock did not exist
2690 public function unlock( $lockName, $method ) {
2695 * Lock specific tables
2697 * @param $read Array of tables to lock for read access
2698 * @param $write Array of tables to lock for write access
2699 * @param $method String name of caller
2700 * @param $lowPriority bool Whether to indicate writes to be LOW PRIORITY
2702 public function lockTables( $read, $write, $method, $lowPriority = true ) {
2707 * Unlock specific tables
2709 * @param $method String the caller
2711 public function unlockTables( $method ) {
2716 * Get search engine class. All subclasses of this need to implement this
2717 * if they wish to use searching.
2721 public function getSearchEngine() {
2722 return 'SearchEngineDummy';
2726 * Allow or deny "big selects" for this session only. This is done by setting
2727 * the sql_big_selects session variable.
2729 * This is a MySQL-specific feature.
2731 * @param $value Mixed: true for allow, false for deny, or "default" to restore the initial value
2733 public function setBigSelects( $value = true ) {
2738 /******************************************************************************
2740 *****************************************************************************/
2749 function __construct( $data ) {
2750 $this->mData = $data;
2758 return $this->mData;
2766 * This allows us to distinguish a blob from a normal string and an array of strings
2771 function __construct( $data ) {
2772 $this->mData = $data;
2776 return $this->mData;
2781 * Base for all database-specific classes representing information about database fields
2792 * Name of table this field belongs to
2795 function tableName();
2804 * Whether this field can store NULL values
2807 function isNullable();
2810 /******************************************************************************
2812 *****************************************************************************/
2815 * Database error base class
2818 class DBError extends MWException {
2822 * Construct a database error
2823 * @param $db Database object which threw the error
2824 * @param $error A simple error message to be used for debugging
2826 function __construct( DatabaseBase &$db, $error ) {
2828 parent::__construct( $error );
2831 function getText() {
2832 global $wgShowDBErrorBacktrace;
2834 $s = $this->getMessage() . "\n";
2836 if ( $wgShowDBErrorBacktrace ) {
2837 $s .= "Backtrace:\n" . $this->getTraceAsString() . "\n";
2847 class DBConnectionError extends DBError {
2850 function __construct( DatabaseBase &$db, $error = 'unknown error' ) {
2851 $msg = 'DB connection error';
2853 if ( trim( $error ) != '' ) {
2857 $this->error = $error;
2859 parent::__construct( $db, $msg );
2862 function useOutputPage() {
2863 // Not likely to work
2867 function useMessageCache() {
2868 // Not likely to work
2872 function getLogMessage() {
2873 # Don't send to the exception log
2877 function getPageTitle() {
2878 global $wgSitename, $wgLang;
2880 $header = "$wgSitename has a problem";
2882 if ( $wgLang instanceof Language ) {
2883 $header = htmlspecialchars( $wgLang->getMessage( 'dberr-header' ) );
2889 function getHTML() {
2890 global $wgLang, $wgMessageCache, $wgUseFileCache, $wgShowDBErrorBacktrace;
2892 $sorry = 'Sorry! This site is experiencing technical difficulties.';
2893 $again = 'Try waiting a few minutes and reloading.';
2894 $info = '(Can\'t contact the database server: $1)';
2896 if ( $wgLang instanceof Language ) {
2897 $sorry = htmlspecialchars( $wgLang->getMessage( 'dberr-problems' ) );
2898 $again = htmlspecialchars( $wgLang->getMessage( 'dberr-again' ) );
2899 $info = htmlspecialchars( $wgLang->getMessage( 'dberr-info' ) );
2902 # No database access
2903 if ( is_object( $wgMessageCache ) ) {
2904 $wgMessageCache->disable();
2907 if ( trim( $this->error ) == '' ) {
2908 $this->error = $this->db->getProperty( 'mServer' );
2911 $noconnect = "<p><strong>$sorry</strong><br />$again</p><p><small>$info</small></p>";
2912 $text = str_replace( '$1', $this->error, $noconnect );
2914 if ( $wgShowDBErrorBacktrace ) {
2915 $text .= '<p>Backtrace:</p><p>' . nl2br( htmlspecialchars( $this->getTraceAsString() ) );
2918 $extra = $this->searchForm();
2920 if ( $wgUseFileCache ) {
2922 $cache = $this->fileCachedPage();
2923 # Cached version on file system?
2924 if ( $cache !== null ) {
2925 # Hack: extend the body for error messages
2926 $cache = str_replace( array( '</html>', '</body>' ), '', $cache );
2927 # Add cache notice...
2928 $cachederror = "This is a cached copy of the requested page, and may not be up to date. ";
2930 # Localize it if possible...
2931 if ( $wgLang instanceof Language ) {
2932 $cachederror = htmlspecialchars( $wgLang->getMessage( 'dberr-cachederror' ) );
2935 $warning = "<div style='color:red;font-size:150%;font-weight:bold;'>$cachederror</div>";
2937 # Output cached page with notices on bottom and re-close body
2938 return "{$cache}{$warning}<hr />$text<hr />$extra</body></html>";
2940 } catch ( MWException $e ) {
2941 // Do nothing, just use the default page
2945 # Headers needed here - output is just the error message
2946 return $this->htmlHeader() . "$text<hr />$extra" . $this->htmlFooter();
2949 function searchForm() {
2950 global $wgSitename, $wgServer, $wgLang;
2952 $usegoogle = "You can try searching via Google in the meantime.";
2953 $outofdate = "Note that their indexes of our content may be out of date.";
2954 $googlesearch = "Search";
2956 if ( $wgLang instanceof Language ) {
2957 $usegoogle = htmlspecialchars( $wgLang->getMessage( 'dberr-usegoogle' ) );
2958 $outofdate = htmlspecialchars( $wgLang->getMessage( 'dberr-outofdate' ) );
2959 $googlesearch = htmlspecialchars( $wgLang->getMessage( 'searchbutton' ) );
2962 $search = htmlspecialchars( @$_REQUEST['search'] );
2964 $server = htmlspecialchars( $wgServer );
2965 $sitename = htmlspecialchars( $wgSitename );
2968 <div style="margin: 1.5em">$usegoogle<br />
2969 <small>$outofdate</small></div>
2970 <!-- SiteSearch Google -->
2971 <form method="get" action="http://www.google.com/search" id="googlesearch">
2972 <input type="hidden" name="domains" value="$server" />
2973 <input type="hidden" name="num" value="50" />
2974 <input type="hidden" name="ie" value="UTF-8" />
2975 <input type="hidden" name="oe" value="UTF-8" />
2977 <input type="text" name="q" size="31" maxlength="255" value="$search" />
2978 <input type="submit" name="btnG" value="$googlesearch" />
2980 <input type="radio" name="sitesearch" id="gwiki" value="$server" checked="checked" /><label for="gwiki">$sitename</label>
2981 <input type="radio" name="sitesearch" id="gWWW" value="" /><label for="gWWW">WWW</label>
2984 <!-- SiteSearch Google -->
2989 function fileCachedPage() {
2990 global $wgTitle, $wgLang, $wgOut;
2992 if ( $wgOut->isDisabled() ) {
2993 return; // Done already?
2996 $mainpage = 'Main Page';
2998 if ( $wgLang instanceof Language ) {
2999 $mainpage = htmlspecialchars( $wgLang->getMessage( 'mainpage' ) );
3005 $t = Title::newFromText( $mainpage );
3008 $cache = new HTMLFileCache( $t );
3009 if ( $cache->isFileCached() ) {
3010 return $cache->fetchPageText();
3016 function htmlBodyOnly() {
3024 class DBQueryError extends DBError {
3025 public $error, $errno, $sql, $fname;
3027 function __construct( DatabaseBase &$db, $error, $errno, $sql, $fname ) {
3028 $message = "A database error has occurred. Did you forget to run maintenance/update.php after upgrading? See: http://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script\n" .
3030 "Function: $fname\n" .
3031 "Error: $errno $error\n";
3033 parent::__construct( $db, $message );
3035 $this->error = $error;
3036 $this->errno = $errno;
3038 $this->fname = $fname;
3041 function getText() {
3042 global $wgShowDBErrorBacktrace;
3044 if ( $this->useMessageCache() ) {
3045 $s = wfMsg( 'dberrortextcl', htmlspecialchars( $this->getSQL() ),
3046 htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) ) . "\n";
3048 if ( $wgShowDBErrorBacktrace ) {
3049 $s .= "Backtrace:\n" . $this->getTraceAsString() . "\n";
3054 return parent::getText();
3059 global $wgShowSQLErrors;
3061 if ( !$wgShowSQLErrors ) {
3062 return $this->msg( 'sqlhidden', 'SQL hidden' );
3068 function getLogMessage() {
3069 # Don't send to the exception log
3073 function getPageTitle() {
3074 return $this->msg( 'databaseerror', 'Database error' );
3077 function getHTML() {
3078 global $wgShowDBErrorBacktrace;
3080 if ( $this->useMessageCache() ) {
3081 $s = wfMsgNoDB( 'dberrortext', htmlspecialchars( $this->getSQL() ),
3082 htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) );
3084 $s = nl2br( htmlspecialchars( $this->getMessage() ) );
3087 if ( $wgShowDBErrorBacktrace ) {
3088 $s .= '<p>Backtrace:</p><p>' . nl2br( htmlspecialchars( $this->getTraceAsString() ) );
3098 class DBUnexpectedError extends DBError {}
3102 * Result wrapper for grabbing data queried by someone else
3105 class ResultWrapper implements Iterator {
3106 var $db, $result, $pos = 0, $currentRow = null;
3109 * Create a new result object from a result resource and a Database object
3111 function __construct( $database, $result ) {
3112 $this->db = $database;
3114 if ( $result instanceof ResultWrapper ) {
3115 $this->result = $result->result;
3117 $this->result = $result;
3122 * Get the number of rows in a result object
3124 function numRows() {
3125 return $this->db->numRows( $this );
3129 * Fetch the next row from the given result object, in object form.
3130 * Fields can be retrieved with $row->fieldname, with fields acting like
3133 * @return MySQL row object
3134 * @throws DBUnexpectedError Thrown if the database returns an error
3136 function fetchObject() {
3137 return $this->db->fetchObject( $this );
3141 * Fetch the next row from the given result object, in associative array
3142 * form. Fields are retrieved with $row['fieldname'].
3144 * @return MySQL row object
3145 * @throws DBUnexpectedError Thrown if the database returns an error
3147 function fetchRow() {
3148 return $this->db->fetchRow( $this );
3152 * Free a result object
3155 $this->db->freeResult( $this );
3156 unset( $this->result );
3161 * Change the position of the cursor in a result object
3162 * See mysql_data_seek()
3164 function seek( $row ) {
3165 $this->db->dataSeek( $this, $row );
3168 /*********************
3169 * Iterator functions
3170 * Note that using these in combination with the non-iterator functions
3171 * above may cause rows to be skipped or repeated.
3175 if ( $this->numRows() ) {
3176 $this->db->dataSeek( $this, 0 );
3179 $this->currentRow = null;
3182 function current() {
3183 if ( is_null( $this->currentRow ) ) {
3186 return $this->currentRow;
3195 $this->currentRow = $this->fetchObject();
3196 return $this->currentRow;
3200 return $this->current() !== false;
3205 * Overloads the relevant methods of the real ResultsWrapper so it
3206 * doesn't go anywhere near an actual database.
3208 class FakeResultWrapper extends ResultWrapper {
3209 var $result = array();
3210 var $db = null; // And it's going to stay that way :D
3212 var $currentRow = null;
3214 function __construct( $array ) {
3215 $this->result = $array;
3218 function numRows() {
3219 return count( $this->result );
3222 function fetchRow() {
3223 $this->currentRow = $this->result[$this->pos++];
3224 return $this->currentRow;
3227 function seek( $row ) {
3233 // Callers want to be able to access fields with $this->fieldName
3234 function fetchObject() {
3235 $this->currentRow = $this->result[$this->pos++];
3236 return (object)$this->currentRow;
3241 $this->currentRow = null;
3246 * Used by DatabaseBase::buildLike() to represent characters that have special meaning in SQL LIKE clauses
3247 * and thus need no escaping. Don't instantiate it manually, use DatabaseBase::anyChar() and anyString() instead.
3252 public function __construct( $s ) {
3256 public function toString() {