includes/db/DatabaseMysql.php

   1 <?php
   2 /**
   3  * This is the MySQL database abstraction layer.
   4  *
   5  * @file
   6  * @ingroup Database
   7  */
   8
   9 /**
  10  * Database abstraction object for mySQL
  11  * Inherit all methods and properties of Database::Database()
  12  *
  13  * @ingroup Database
  14  * @see Database
  15  */
  16 class DatabaseMysql extends DatabaseBase {
  17         function getType() {
  18                 return 'mysql';
  19         }
  20
  21         protected function doQuery( $sql ) {
  22                 if( $this->bufferResults() ) {
  23                         $ret = mysql_query( $sql, $this->mConn );
  24                 } else {
  25                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
  26                 }
  27                 return $ret;
  28         }
  29
  30         function open( $server, $user, $password, $dbName ) {
  31                 global $wgAllDBsAreLocalhost;
  32                 wfProfileIn( __METHOD__ );
  33
  34                 # Load mysql.so if we don't have it
  35                 wfDl( 'mysql' );
  36
  37                 # Fail now
  38                 # Otherwise we get a suppressed fatal error, which is very hard to track down
  39                 if ( !function_exists( 'mysql_connect' ) ) {
  40                         throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
  41                 }
  42
  43                 # Debugging hack -- fake cluster
  44                 if ( $wgAllDBsAreLocalhost ) {
  45                         $realServer = 'localhost';
  46                 } else {
  47                         $realServer = $server;
  48                 }
  49                 $this->close();
  50                 $this->mServer = $server;
  51                 $this->mUser = $user;
  52                 $this->mPassword = $password;
  53                 $this->mDBname = $dbName;
  54
  55                 wfProfileIn("dbconnect-$server");
  56
  57                 # The kernel's default SYN retransmission period is far too slow for us,
  58                 # so we use a short timeout plus a manual retry. Retrying means that a small
  59                 # but finite rate of SYN packet loss won't cause user-visible errors.
  60                 $this->mConn = false;
  61                 if ( ini_get( 'mysql.connect_timeout' ) <= 3 ) {
  62                         $numAttempts = 2;
  63                 } else {
  64                         $numAttempts = 1;
  65                 }
  66                 $this->installErrorHandler();
  67                 for ( $i = 0; $i < $numAttempts && !$this->mConn; $i++ ) {
  68                         if ( $i > 1 ) {
  69                                 usleep( 1000 );
  70                         }
  71                         if ( $this->mFlags & DBO_PERSISTENT ) {
  72                                 $this->mConn = mysql_pconnect( $realServer, $user, $password );
  73                         } else {
  74                                 # Create a new connection...
  75                                 $this->mConn = mysql_connect( $realServer, $user, $password, true );
  76                         }
  77                         #if ( $this->mConn === false ) {
  78                                 #$iplus = $i + 1;
  79                                 #wfLogDBError("Connect loop error $iplus of $max ($server): " . mysql_errno() . " - " . mysql_error()."\n");
  80                         #}
  81                 }
  82                 $phpError = $this->restoreErrorHandler();
  83                 # Always log connection errors
  84                 if ( !$this->mConn ) {
  85                         $error = $this->lastError();
  86                         if ( !$error ) {
  87                                 $error = $phpError;
  88                         }
  89                         wfLogDBError( "Error connecting to {$this->mServer}: $error\n" );
  90                         wfDebug( "DB connection error\n" );
  91                         wfDebug( "Server: $server, User: $user, Password: " .
  92                                 substr( $password, 0, 3 ) . "..., error: " . mysql_error() . "\n" );
  93                 }
  94
  95                 wfProfileOut("dbconnect-$server");
  96
  97                 if ( $dbName != '' && $this->mConn !== false ) {
  98                         $success = @/**/mysql_select_db( $dbName, $this->mConn );
  99                         if ( !$success ) {
 100                                 $error = "Error selecting database $dbName on server {$this->mServer} " .
 101                                         "from client host " . wfHostname() . "\n";
 102                                 wfLogDBError(" Error selecting database $dbName on server {$this->mServer} \n");
 103                                 wfDebug( $error );
 104                         }
 105                 } else {
 106                         # Delay USE query
 107                         $success = (bool)$this->mConn;
 108                 }
 109
 110                 if ( $success ) {
 111                         $version = $this->getServerVersion();
 112                         if ( version_compare( $version, '4.1' ) >= 0 ) {
 113                                 // Tell the server we're communicating with it in UTF-8.
 114                                 // This may engage various charset conversions.
 115                                 global $wgDBmysql5;
 116                                 if( $wgDBmysql5 ) {
 117                                         $this->query( 'SET NAMES utf8', __METHOD__ );
 118                                 } else {
 119                                         $this->query( 'SET NAMES binary', __METHOD__ );
 120                                 }
 121                                 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
 122                                 global $wgSQLMode;
 123                                 if ( is_string( $wgSQLMode ) ) {
 124                                         $mode = $this->addQuotes( $wgSQLMode );
 125                                         $this->query( "SET sql_mode = $mode", __METHOD__ );
 126                                 }
 127                         }
 128
 129                         // Turn off strict mode if it is on
 130                 } else {
 131                         $this->reportConnectionError( $phpError );
 132                 }
 133
 134                 $this->mOpened = $success;
 135                 wfProfileOut( __METHOD__ );
 136                 return $success;
 137         }
 138
 139         function close() {
 140                 $this->mOpened = false;
 141                 if ( $this->mConn ) {
 142                         if ( $this->trxLevel() ) {
 143                                 $this->commit();
 144                         }
 145                         return mysql_close( $this->mConn );
 146                 } else {
 147                         return true;
 148                 }
 149         }
 150
 151         function freeResult( $res ) {
 152                 if ( $res instanceof ResultWrapper ) {
 153                         $res = $res->result;
 154                 }
 155                 if ( !@/**/mysql_free_result( $res ) ) {
 156                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 157                 }
 158         }
 159
 160         function fetchObject( $res ) {
 161                 if ( $res instanceof ResultWrapper ) {
 162                         $res = $res->result;
 163                 }
 164                 @/**/$row = mysql_fetch_object( $res );
 165                 if( $this->lastErrno() ) {
 166                         throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
 167                 }
 168                 return $row;
 169         }
 170
 171         function fetchRow( $res ) {
 172                 if ( $res instanceof ResultWrapper ) {
 173                         $res = $res->result;
 174                 }
 175                 @/**/$row = mysql_fetch_array( $res );
 176                 if ( $this->lastErrno() ) {
 177                         throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
 178                 }
 179                 return $row;
 180         }
 181
 182         function numRows( $res ) {
 183                 if ( $res instanceof ResultWrapper ) {
 184                         $res = $res->result;
 185                 }
 186                 @/**/$n = mysql_num_rows( $res );
 187                 if( $this->lastErrno() ) {
 188                         throw new DBUnexpectedError( $this, 'Error in numRows(): ' . htmlspecialchars( $this->lastError() ) );
 189                 }
 190                 return $n;
 191         }
 192
 193         function numFields( $res ) {
 194                 if ( $res instanceof ResultWrapper ) {
 195                         $res = $res->result;
 196                 }
 197                 return mysql_num_fields( $res );
 198         }
 199
 200         function fieldName( $res, $n ) {
 201                 if ( $res instanceof ResultWrapper ) {
 202                         $res = $res->result;
 203                 }
 204                 return mysql_field_name( $res, $n );
 205         }
 206
 207         function insertId() { return mysql_insert_id( $this->mConn ); }
 208
 209         function dataSeek( $res, $row ) {
 210                 if ( $res instanceof ResultWrapper ) {
 211                         $res = $res->result;
 212                 }
 213                 return mysql_data_seek( $res, $row );
 214         }
 215
 216         function lastErrno() {
 217                 if ( $this->mConn ) {
 218                         return mysql_errno( $this->mConn );
 219                 } else {
 220                         return mysql_errno();
 221                 }
 222         }
 223
 224         function lastError() {
 225                 if ( $this->mConn ) {
 226                         # Even if it's non-zero, it can still be invalid
 227                         wfSuppressWarnings();
 228                         $error = mysql_error( $this->mConn );
 229                         if ( !$error ) {
 230                                 $error = mysql_error();
 231                         }
 232                         wfRestoreWarnings();
 233                 } else {
 234                         $error = mysql_error();
 235                 }
 236                 if( $error ) {
 237                         $error .= ' (' . $this->mServer . ')';
 238                 }
 239                 return $error;
 240         }
 241
 242         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
 243
 244         function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseMysql::replace' ) {
 245                 return $this->nativeReplace( $table, $rows, $fname );
 246         }
 247
 248         /**
 249          * Estimate rows in dataset
 250          * Returns estimated count, based on EXPLAIN output
 251          * Takes same arguments as Database::select()
 252          */
 253         public function estimateRowCount( $table, $vars='*', $conds='', $fname = 'DatabaseMysql::estimateRowCount', $options = array() ) {
 254                 $options['EXPLAIN'] = true;
 255                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 256                 if ( $res === false ) {
 257                         return false;
 258                 }
 259                 if ( !$this->numRows( $res ) ) {
 260                         return 0;
 261                 }
 262
 263                 $rows = 1;
 264                 foreach ( $res as $plan ) {
 265                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 266                 }
 267                 return $rows;
 268         }
 269
 270         function fieldInfo( $table, $field ) {
 271                 $table = $this->tableName( $table );
 272                 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__, true );
 273                 if ( !$res ) {
 274                         return false;
 275                 }
 276                 $n = mysql_num_fields( $res->result );
 277                 for( $i = 0; $i < $n; $i++ ) {
 278                         $meta = mysql_fetch_field( $res->result, $i );
 279                         if( $field == $meta->name ) {
 280                                 return new MySQLField($meta);
 281                         }
 282                 }
 283                 return false;
 284         }
 285
 286         /**
 287          * Get information about an index into an object
 288          * Returns false if the index does not exist
 289          */
 290         function indexInfo( $table, $index, $fname = 'DatabaseMysql::indexInfo' ) {
 291                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 292                 # SHOW INDEX should work for 3.x and up:
 293                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 294                 $table = $this->tableName( $table );
 295                 $index = $this->indexName( $index );
 296                 $sql = 'SHOW INDEX FROM ' . $table;
 297                 $res = $this->query( $sql, $fname );
 298
 299                 if ( !$res ) {
 300                         return null;
 301                 }
 302
 303                 $result = array();
 304
 305                 foreach ( $res as $row ) {
 306                         if ( $row->Key_name == $index ) {
 307                                 $result[] = $row;
 308                         }
 309                 }
 310
 311                 return empty( $result ) ? false : $result;
 312         }
 313
 314         function selectDB( $db ) {
 315                 $this->mDBname = $db;
 316                 return mysql_select_db( $db, $this->mConn );
 317         }
 318
 319         function strencode( $s ) {
 320                 $sQuoted = mysql_real_escape_string( $s, $this->mConn );
 321
 322                 if($sQuoted === false) {
 323                         $this->ping();
 324                         $sQuoted = mysql_real_escape_string( $s, $this->mConn );
 325                 }
 326                 return $sQuoted;
 327         }
 328
 329         /**
 330          * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
 331          */
 332         public function addIdentifierQuotes( $s ) {
 333                 return "`" . $this->strencode( $s ) . "`";
 334         }
 335
 336         public function isQuotedIdentifier( $name ) {
 337                 return strlen($name) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
 338         }
 339
 340         function ping() {
 341                 $ping = mysql_ping( $this->mConn );
 342                 if ( $ping ) {
 343                         return true;
 344                 }
 345
 346                 mysql_close( $this->mConn );
 347                 $this->mOpened = false;
 348                 $this->mConn = false;
 349                 $this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
 350                 return true;
 351         }
 352
 353         /**
 354          * Returns slave lag.
 355          *
 356          * On MySQL 4.1.9 and later, this will do a SHOW SLAVE STATUS. On earlier
 357          * versions of MySQL, it uses SHOW PROCESSLIST, which requires the PROCESS
 358          * privilege.
 359          *
 360          * @result int
 361          */
 362         function getLag() {
 363                 if ( !is_null( $this->mFakeSlaveLag ) ) {
 364                         wfDebug( "getLag: fake slave lagged {$this->mFakeSlaveLag} seconds\n" );
 365                         return $this->mFakeSlaveLag;
 366                 }
 367
 368                 /*if ( version_compare( $this->getServerVersion(), '4.1.9', '>=' ) ) {
 369                         return $this->getLagFromSlaveStatus();
 370                 } else */{
 371                         return $this->getLagFromProcesslist();
 372                 }
 373         }
 374
 375         function getLagFromSlaveStatus() {
 376                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 377                 if ( !$res ) {
 378                         return false;
 379                 }
 380                 $row = $res->fetchObject();
 381                 if ( !$row ) {
 382                         return false;
 383                 }
 384                 if ( strval( $row->Seconds_Behind_Master ) === '' ) {
 385                         return false;
 386                 } else {
 387                         return intval( $row->Seconds_Behind_Master );
 388                 }
 389         }
 390
 391         function getLagFromProcesslist() {
 392                 $res = $this->query( 'SHOW PROCESSLIST', __METHOD__ );
 393                 if( !$res ) {
 394                         return false;
 395                 }
 396                 # Find slave SQL thread
 397                 foreach( $res as $row ) {
 398                         /* This should work for most situations - when default db
 399                          * for thread is not specified, it had no events executed,
 400                          * and therefore it doesn't know yet how lagged it is.
 401                          *
 402                          * Relay log I/O thread does not select databases.
 403                          */
 404                         if ( $row->User == 'system user' &&
 405                                 $row->State != 'Waiting for master to send event' &&
 406                                 $row->State != 'Connecting to master' &&
 407                                 $row->State != 'Queueing master event to the relay log' &&
 408                                 $row->State != 'Waiting for master update' &&
 409                                 $row->State != 'Requesting binlog dump' &&
 410                                 $row->State != 'Waiting to reconnect after a failed master event read' &&
 411                                 $row->State != 'Reconnecting after a failed master event read' &&
 412                                 $row->State != 'Registering slave on master'
 413                                 ) {
 414                                 # This is it, return the time (except -ve)
 415                                 if ( $row->Time > 0x7fffffff ) {
 416                                         return false;
 417                                 } else {
 418                                         return $row->Time;
 419                                 }
 420                         }
 421                 }
 422                 return false;
 423         }
 424
 425         /**
 426          * Wait for the slave to catch up to a given master position.
 427          *
 428          * @param $pos DBMasterPos object
 429          * @param $timeout Integer: the maximum number of seconds to wait for synchronisation
 430          */
 431         function masterPosWait( DBMasterPos $pos, $timeout ) {
 432                 $fname = 'DatabaseBase::masterPosWait';
 433                 wfProfileIn( $fname );
 434
 435                 # Commit any open transactions
 436                 if ( $this->mTrxLevel ) {
 437                         $this->commit();
 438                 }
 439
 440                 if ( !is_null( $this->mFakeSlaveLag ) ) {
 441                         $status = parent::masterPosWait( $pos, $timeout );
 442                         wfProfileOut( $fname );
 443                         return $status;
 444                 }
 445
 446                 # Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
 447                 $encFile = $this->addQuotes( $pos->file );
 448                 $encPos = intval( $pos->pos );
 449                 $sql = "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)";
 450                 $res = $this->doQuery( $sql );
 451
 452                 if ( $res && $row = $this->fetchRow( $res ) ) {
 453                         wfProfileOut( $fname );
 454                         return $row[0];
 455                 } else {
 456                         wfProfileOut( $fname );
 457                         return false;
 458                 }
 459         }
 460
 461         /**
 462          * Get the position of the master from SHOW SLAVE STATUS
 463          *
 464          * @return MySQLMasterPos|false
 465          */
 466         function getSlavePos() {
 467                 if ( !is_null( $this->mFakeSlaveLag ) ) {
 468                         return parent::getSlavePos();
 469                 }
 470
 471                 $res = $this->query( 'SHOW SLAVE STATUS', 'DatabaseBase::getSlavePos' );
 472                 $row = $this->fetchObject( $res );
 473
 474                 if ( $row ) {
 475                         $pos = isset( $row->Exec_master_log_pos ) ? $row->Exec_master_log_pos : $row->Exec_Master_Log_Pos;
 476                         return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos );
 477                 } else {
 478                         return false;
 479                 }
 480         }
 481
 482         /**
 483          * Get the position of the master from SHOW MASTER STATUS
 484          *
 485          * @return MySQLMasterPos|false
 486          */
 487         function getMasterPos() {
 488                 if ( $this->mFakeMaster ) {
 489                         return parent::getMasterPos();
 490                 }
 491
 492                 $res = $this->query( 'SHOW MASTER STATUS', 'DatabaseBase::getMasterPos' );
 493                 $row = $this->fetchObject( $res );
 494
 495                 if ( $row ) {
 496                         return new MySQLMasterPos( $row->File, $row->Position );
 497                 } else {
 498                         return false;
 499                 }
 500         }
 501
 502         function getServerVersion() {
 503                 return mysql_get_server_info( $this->mConn );
 504         }
 505
 506         function useIndexClause( $index ) {
 507                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 508         }
 509
 510         function lowPriorityOption() {
 511                 return 'LOW_PRIORITY';
 512         }
 513
 514         public static function getSoftwareLink() {
 515                 return '[http://www.mysql.com/ MySQL]';
 516         }
 517
 518         function standardSelectDistinct() {
 519                 return false;
 520         }
 521
 522         public function setTimeout( $timeout ) {
 523                 $this->query( "SET net_read_timeout=$timeout" );
 524                 $this->query( "SET net_write_timeout=$timeout" );
 525         }
 526
 527         public function lock( $lockName, $method, $timeout = 5 ) {
 528                 $lockName = $this->addQuotes( $lockName );
 529                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 530                 $row = $this->fetchObject( $result );
 531
 532                 if( $row->lockstatus == 1 ) {
 533                         return true;
 534                 } else {
 535                         wfDebug( __METHOD__." failed to acquire lock\n" );
 536                         return false;
 537                 }
 538         }
 539
 540         /**
 541          * FROM MYSQL DOCS: http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
 542          */
 543         public function unlock( $lockName, $method ) {
 544                 $lockName = $this->addQuotes( $lockName );
 545                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 546                 $row = $this->fetchObject( $result );
 547                 return $row->lockstatus;
 548         }
 549
 550         public function lockTables( $read, $write, $method, $lowPriority = true ) {
 551                 $items = array();
 552
 553                 foreach( $write as $table ) {
 554                         $tbl = $this->tableName( $table ) .
 555                                         ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
 556                                         ' WRITE';
 557                         $items[] = $tbl;
 558                 }
 559                 foreach( $read as $table ) {
 560                         $items[] = $this->tableName( $table ) . ' READ';
 561                 }
 562                 $sql = "LOCK TABLES " . implode( ',', $items );
 563                 $this->query( $sql, $method );
 564         }
 565
 566         public function unlockTables( $method ) {
 567                 $this->query( "UNLOCK TABLES", $method );
 568         }
 569
 570         /**
 571          * Get search engine class. All subclasses of this
 572          * need to implement this if they wish to use searching.
 573          *
 574          * @return String
 575          */
 576         public function getSearchEngine() {
 577                 return 'SearchMySQL';
 578         }
 579
 580         public function setBigSelects( $value = true ) {
 581                 if ( $value === 'default' ) {
 582                         if ( $this->mDefaultBigSelects === null ) {
 583                                 # Function hasn't been called before so it must already be set to the default
 584                                 return;
 585                         } else {
 586                                 $value = $this->mDefaultBigSelects;
 587                         }
 588                 } elseif ( $this->mDefaultBigSelects === null ) {
 589                         $this->mDefaultBigSelects = (bool)$this->selectField( false, '@@sql_big_selects' );
 590                 }
 591                 $encValue = $value ? '1' : '0';
 592                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
 593         }
 594
 595         /**
 596          * DELETE where the condition is a join. MySql uses multi-table deletes.
 597          */
 598         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'DatabaseBase::deleteJoin' ) {
 599                 if ( !$conds ) {
 600                         throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
 601                 }
 602
 603                 $delTable = $this->tableName( $delTable );
 604                 $joinTable = $this->tableName( $joinTable );
 605                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
 606
 607                 if ( $conds != '*' ) {
 608                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
 609                 }
 610
 611                 return $this->query( $sql, $fname );
 612         }
 613
 614         /**
 615          * Determines if the last failure was due to a deadlock
 616          */
 617         function wasDeadlock() {
 618                 return $this->lastErrno() == 1213;
 619         }
 620
 621         /**
 622          * Determines if the last query error was something that should be dealt
 623          * with by pinging the connection and reissuing the query
 624          */
 625         function wasErrorReissuable() {
 626                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
 627         }
 628
 629         /**
 630          * Determines if the last failure was due to the database being read-only.
 631          */
 632         function wasReadOnlyError() {
 633                 return $this->lastErrno() == 1223 ||
 634                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
 635         }
 636
 637         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabaseMysql::duplicateTableStructure' ) {
 638                 $tmp = $temporary ? 'TEMPORARY ' : '';
 639                 if ( strcmp( $this->getServerVersion(), '4.1' ) < 0 ) {
 640                         # Hack for MySQL versions < 4.1, which don't support
 641                         # "CREATE TABLE ... LIKE". Note that
 642                         # "CREATE TEMPORARY TABLE ... SELECT * FROM ... LIMIT 0"
 643                         # would not create the indexes we need....
 644                         #
 645                         # Note that we don't bother changing around the prefixes here be-
 646                         # cause we know we're using MySQL anyway.
 647
 648                         $res = $this->query( 'SHOW CREATE TABLE ' . $this->addIdentifierQuotes( $oldName ) );
 649                         $row = $this->fetchRow( $res );
 650                         $oldQuery = $row[1];
 651                         $query = preg_replace( '/CREATE TABLE `(.*?)`/',
 652                                 "CREATE $tmp TABLE " . $this->addIdentifierQuotes( $newName ), $oldQuery );
 653                         if ($oldQuery === $query) {
 654                                 # Couldn't do replacement
 655                                 throw new MWException( "could not create temporary table $newName" );
 656                         }
 657                 } else {
 658                         $newName = $this->addIdentifierQuotes( $newName );
 659                         $oldName = $this->addIdentifierQuotes( $oldName );
 660                         $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
 661                 }
 662                 $this->query( $query, $fname );
 663         }
 664
 665         /**
 666          * List all tables on the database
 667          *
 668          * @param $prefix Only show tables with this prefix, e.g. mw_
 669          * @param $fname String: calling function name
 670          */
 671         function listTables( $prefix = null, $fname = 'DatabaseMysql::listTables' ) {
 672                 $result = $this->query( "SHOW TABLES", $fname);
 673
 674                 $endArray = array();
 675
 676                 foreach( $result as $table ) {
 677                         $vars = get_object_vars($table);
 678                         $table = array_pop( $vars );
 679
 680                         if( !$prefix || strpos( $table, $prefix ) === 0 ) {
 681                                 $endArray[] = $table;
 682                         }
 683                 }
 684
 685                 return $endArray;
 686         }
 687
 688         public function dropTable( $tableName, $fName = 'DatabaseMysql::dropTable' ) {
 689                 if( !$this->tableExists( $tableName ) ) {
 690                         return false;
 691                 }
 692                 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
 693         }
 694
 695         protected function getDefaultSchemaVars() {
 696                 $vars = parent::getDefaultSchemaVars();
 697                 $vars['wgDBTableOptions'] = $GLOBALS['wgDBTableOptions'];
 698                 return $vars;
 699         }
 700
 701         /**
 702          * Get status information from SHOW STATUS in an associative array
 703          *
 704          * @return array
 705          */
 706         function getMysqlStatus( $which = "%" ) {
 707                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
 708                 $status = array();
 709
 710                 foreach ( $res as $row ) {
 711                         $status[$row->Variable_name] = $row->Value;
 712                 }
 713
 714                 return $status;
 715         }
 716
 717 }
 718
 719 /**
 720  * Legacy support: Database == DatabaseMysql
 721  */
 722 class Database extends DatabaseMysql {}
 723
 724 /**
 725  * Utility class.
 726  * @ingroup Database
 727  */
 728 class MySQLField implements Field {
 729         private $name, $tablename, $default, $max_length, $nullable,
 730                 $is_pk, $is_unique, $is_multiple, $is_key, $type;
 731
 732         function __construct ( $info ) {
 733                 $this->name = $info->name;
 734                 $this->tablename = $info->table;
 735                 $this->default = $info->def;
 736                 $this->max_length = $info->max_length;
 737                 $this->nullable = !$info->not_null;
 738                 $this->is_pk = $info->primary_key;
 739                 $this->is_unique = $info->unique_key;
 740                 $this->is_multiple = $info->multiple_key;
 741                 $this->is_key = ( $this->is_pk || $this->is_unique || $this->is_multiple );
 742                 $this->type = $info->type;
 743         }
 744
 745         function name() {
 746                 return $this->name;
 747         }
 748
 749         function tableName() {
 750                 return $this->tableName;
 751         }
 752
 753         function type() {
 754                 return $this->type;
 755         }
 756
 757         function isNullable() {
 758                 return $this->nullable;
 759         }
 760
 761         function defaultValue() {
 762                 return $this->default;
 763         }
 764
 765         function isKey() {
 766                 return $this->is_key;
 767         }
 768
 769         function isMultipleKey() {
 770                 return $this->is_multiple;
 771         }
 772 }
 773
 774 class MySQLMasterPos implements DBMasterPos {
 775         var $file, $pos;
 776
 777         function __construct( $file, $pos ) {
 778                 $this->file = $file;
 779                 $this->pos = $pos;
 780         }
 781
 782         function __toString() {
 783                 return "{$this->file}/{$this->pos}";
 784         }
 785 }