includes/Database.php

   1 <?php
   2 /**
   3  * This file deals with MySQL interface functions
   4  * and query specifics/optimisations
   5  */
   6
   7 /** Number of times to re-try an operation in case of deadlock */
   8 define( 'DEADLOCK_TRIES', 4 );
   9 /** Minimum time to wait before retry, in microseconds */
  10 define( 'DEADLOCK_DELAY_MIN', 500000 );
  11 /** Maximum time to wait before retry */
  12 define( 'DEADLOCK_DELAY_MAX', 1500000 );
  13
  14 /******************************************************************************
  15  * Utility classes
  16  *****************************************************************************/
  17
  18 /**
  19  * Utility class.
  20  * @addtogroup Database
  21  */
  22 class DBObject {
  23         public $mData;
  24
  25         function DBObject($data) {
  26                 $this->mData = $data;
  27         }
  28
  29         function isLOB() {
  30                 return false;
  31         }
  32
  33         function data() {
  34                 return $this->mData;
  35         }
  36 };
  37
  38 /**
  39  * Utility class.
  40  * @addtogroup Database
  41  */
  42 class MySQLField {
  43         private $name, $tablename, $default, $max_length, $nullable,
  44                 $is_pk, $is_unique, $is_key, $type;
  45         function __construct ($info) {
  46                 $this->name = $info->name;
  47                 $this->tablename = $info->table;
  48                 $this->default = $info->def;
  49                 $this->max_length = $info->max_length;
  50                 $this->nullable = !$info->not_null;
  51                 $this->is_pk = $info->primary_key;
  52                 $this->is_unique = $info->unique_key;
  53                 $this->is_multiple = $info->multiple_key;
  54                 $this->is_key = ($this->is_pk || $this->is_unique || $this->is_multiple);
  55                 $this->type = $info->type;
  56         }
  57
  58         function name() {
  59                 return $this->name;
  60         }
  61
  62         function tableName() {
  63                 return $this->tableName;
  64         }
  65
  66         function defaultValue() {
  67                 return $this->default;
  68         }
  69
  70         function maxLength() {
  71                 return $this->max_length;
  72         }
  73
  74         function nullable() {
  75                 return $this->nullable;
  76         }
  77
  78         function isKey() {
  79                 return $this->is_key;
  80         }
  81
  82         function isMultipleKey() {
  83                 return $this->is_multiple;
  84         }
  85
  86         function type() {
  87                 return $this->type;
  88         }
  89 }
  90
  91 /******************************************************************************
  92  * Error classes
  93  *****************************************************************************/
  94
  95 /**
  96  * Database error base class
  97  * @addtogroup Database
  98  */
  99 class DBError extends MWException {
 100         public $db;
 101
 102         /**
 103          * Construct a database error
 104          * @param Database $db The database object which threw the error
 105          * @param string $error A simple error message to be used for debugging
 106          */
 107         function __construct( Database &$db, $error ) {
 108                 $this->db =& $db;
 109                 parent::__construct( $error );
 110         }
 111 }
 112
 113 /**
 114  * @addtogroup Database
 115  */
 116 class DBConnectionError extends DBError {
 117         public $error;
 118
 119         function __construct( Database &$db, $error = 'unknown error' ) {
 120                 $msg = 'DB connection error';
 121                 if ( trim( $error ) != '' ) {
 122                         $msg .= ": $error";
 123                 }
 124                 $this->error = $error;
 125                 parent::__construct( $db, $msg );
 126         }
 127
 128         function useOutputPage() {
 129                 // Not likely to work
 130                 return false;
 131         }
 132
 133         function useMessageCache() {
 134                 // Not likely to work
 135                 return false;
 136         }
 137
 138         function getText() {
 139                 return $this->getMessage() . "\n";
 140         }
 141
 142         function getLogMessage() {
 143                 # Don't send to the exception log
 144                 return false;
 145         }
 146
 147         function getPageTitle() {
 148                 global $wgSitename;
 149                 return "$wgSitename has a problem";
 150         }
 151
 152         function getHTML() {
 153                 global $wgTitle, $wgUseFileCache, $title, $wgInputEncoding;
 154                 global $wgSitename, $wgServer, $wgMessageCache;
 155
 156                 # I give up, Brion is right. Getting the message cache to work when there is no DB is tricky.
 157                 # Hard coding strings instead.
 158
 159                 $noconnect = "<p><strong>Sorry! This site is experiencing technical difficulties.</strong></p><p>Try waiting a few minutes and reloading.</p><p><small>(Can't contact the database server: $1)</small></p>";
 160                 $mainpage = 'Main Page';
 161                 $searchdisabled = <<<EOT
 162 <p style="margin: 1.5em 2em 1em">$wgSitename search is disabled for performance reasons. You can search via Google in the meantime.
 163 <span style="font-size: 89%; display: block; margin-left: .2em">Note that their indexes of $wgSitename content may be out of date.</span></p>',
 164 EOT;
 165
 166                 $googlesearch = "
 167 <!-- SiteSearch Google -->
 168 <FORM method=GET action=\"http://www.google.com/search\">
 169 <TABLE bgcolor=\"#FFFFFF\"><tr><td>
 170 <A HREF=\"http://www.google.com/\">
 171 <IMG SRC=\"http://www.google.com/logos/Logo_40wht.gif\"
 172 border=\"0\" ALT=\"Google\"></A>
 173 </td>
 174 <td>
 175 <INPUT TYPE=text name=q size=31 maxlength=255 value=\"$1\">
 176 <INPUT type=submit name=btnG VALUE=\"Google Search\">
 177 <font size=-1>
 178 <input type=hidden name=domains value=\"$wgServer\"><br /><input type=radio name=sitesearch value=\"\"> WWW <input type=radio name=sitesearch value=\"$wgServer\" checked> $wgServer <br />
 179 <input type='hidden' name='ie' value='$2'>
 180 <input type='hidden' name='oe' value='$2'>
 181 </font>
 182 </td></tr></TABLE>
 183 </FORM>
 184 <!-- SiteSearch Google -->";
 185                 $cachederror = "The following is a cached copy of the requested page, and may not be up to date. ";
 186
 187                 # No database access
 188                 if ( is_object( $wgMessageCache ) ) {
 189                         $wgMessageCache->disable();
 190                 }
 191
 192                 if ( trim( $this->error ) == '' ) {
 193                         $this->error = $this->db->getProperty('mServer');
 194                 }
 195
 196                 $text = str_replace( '$1', $this->error, $noconnect );
 197                 $text .= wfGetSiteNotice();
 198
 199                 if($wgUseFileCache) {
 200                         if($wgTitle) {
 201                                 $t =& $wgTitle;
 202                         } else {
 203                                 if($title) {
 204                                         $t = Title::newFromURL( $title );
 205                                 } elseif (@/**/$_REQUEST['search']) {
 206                                         $search = $_REQUEST['search'];
 207                                         return $searchdisabled .
 208                                           str_replace( array( '$1', '$2' ), array( htmlspecialchars( $search ),
 209                                           $wgInputEncoding ), $googlesearch );
 210                                 } else {
 211                                         $t = Title::newFromText( $mainpage );
 212                                 }
 213                         }
 214
 215                         $cache = new HTMLFileCache( $t );
 216                         if( $cache->isFileCached() ) {
 217                                 // FIXME: $msg is not defined on the next line.
 218                                 $msg = '<p style="color: red"><b>'.$msg."<br />\n" .
 219                                         $cachederror . "</b></p>\n";
 220
 221                                 $tag = '<div id="article">';
 222                                 $text = str_replace(
 223                                         $tag,
 224                                         $tag . $msg,
 225                                         $cache->fetchPageText() );
 226                         }
 227                 }
 228
 229                 return $text;
 230         }
 231 }
 232
 233 /**
 234  * @addtogroup Database
 235  */
 236 class DBQueryError extends DBError {
 237         public $error, $errno, $sql, $fname;
 238
 239         function __construct( Database &$db, $error, $errno, $sql, $fname ) {
 240                 $message = "A database error has occurred\n" .
 241                   "Query: $sql\n" .
 242                   "Function: $fname\n" .
 243                   "Error: $errno $error\n";
 244
 245                 parent::__construct( $db, $message );
 246                 $this->error = $error;
 247                 $this->errno = $errno;
 248                 $this->sql = $sql;
 249                 $this->fname = $fname;
 250         }
 251
 252         function getText() {
 253                 if ( $this->useMessageCache() ) {
 254                         return wfMsg( 'dberrortextcl', htmlspecialchars( $this->getSQL() ),
 255                           htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) ) . "\n";
 256                 } else {
 257                         return $this->getMessage();
 258                 }
 259         }
 260
 261         function getSQL() {
 262                 global $wgShowSQLErrors;
 263                 if( !$wgShowSQLErrors ) {
 264                         return $this->msg( 'sqlhidden', 'SQL hidden' );
 265                 } else {
 266                         return $this->sql;
 267                 }
 268         }
 269
 270         function getLogMessage() {
 271                 # Don't send to the exception log
 272                 return false;
 273         }
 274
 275         function getPageTitle() {
 276                 return $this->msg( 'databaseerror', 'Database error' );
 277         }
 278
 279         function getHTML() {
 280                 if ( $this->useMessageCache() ) {
 281                         return wfMsgNoDB( 'dberrortext', htmlspecialchars( $this->getSQL() ),
 282                           htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) );
 283                 } else {
 284                         return nl2br( htmlspecialchars( $this->getMessage() ) );
 285                 }
 286         }
 287 }
 288
 289 /**
 290  * @addtogroup Database
 291  */
 292 class DBUnexpectedError extends DBError {}
 293
 294 /******************************************************************************/
 295
 296 /**
 297  * Database abstraction object
 298  * @addtogroup Database
 299  */
 300 class Database {
 301
 302 #------------------------------------------------------------------------------
 303 # Variables
 304 #------------------------------------------------------------------------------
 305
 306         protected $mLastQuery = '';
 307
 308         protected $mServer, $mUser, $mPassword, $mConn = null, $mDBname;
 309         protected $mOut, $mOpened = false;
 310
 311         protected $mFailFunction;
 312         protected $mTablePrefix;
 313         protected $mFlags;
 314         protected $mTrxLevel = 0;
 315         protected $mErrorCount = 0;
 316         protected $mLBInfo = array();
 317
 318 #------------------------------------------------------------------------------
 319 # Accessors
 320 #------------------------------------------------------------------------------
 321         # These optionally set a variable and return the previous state
 322
 323         /**
 324          * Fail function, takes a Database as a parameter
 325          * Set to false for default, 1 for ignore errors
 326          */
 327         function failFunction( $function = NULL ) {
 328                 return wfSetVar( $this->mFailFunction, $function );
 329         }
 330
 331         /**
 332          * Output page, used for reporting errors
 333          * FALSE means discard output
 334          */
 335         function setOutputPage( $out ) {
 336                 $this->mOut = $out;
 337         }
 338
 339         /**
 340          * Boolean, controls output of large amounts of debug information
 341          */
 342         function debug( $debug = NULL ) {
 343                 return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
 344         }
 345
 346         /**
 347          * Turns buffering of SQL result sets on (true) or off (false).
 348          * Default is "on" and it should not be changed without good reasons.
 349          */
 350         function bufferResults( $buffer = NULL ) {
 351                 if ( is_null( $buffer ) ) {
 352                         return !(bool)( $this->mFlags & DBO_NOBUFFER );
 353                 } else {
 354                         return !wfSetBit( $this->mFlags, DBO_NOBUFFER, !$buffer );
 355                 }
 356         }
 357
 358         /**
 359          * Turns on (false) or off (true) the automatic generation and sending
 360          * of a "we're sorry, but there has been a database error" page on
 361          * database errors. Default is on (false). When turned off, the
 362          * code should use lastErrno() and lastError() to handle the
 363          * situation as appropriate.
 364          */
 365         function ignoreErrors( $ignoreErrors = NULL ) {
 366                 return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors );
 367         }
 368
 369         /**
 370          * The current depth of nested transactions
 371          * @param $level Integer: , default NULL.
 372          */
 373         function trxLevel( $level = NULL ) {
 374                 return wfSetVar( $this->mTrxLevel, $level );
 375         }
 376
 377         /**
 378          * Number of errors logged, only useful when errors are ignored
 379          */
 380         function errorCount( $count = NULL ) {
 381                 return wfSetVar( $this->mErrorCount, $count );
 382         }
 383
 384         /**
 385          * Properties passed down from the server info array of the load balancer
 386          */
 387         function getLBInfo( $name = NULL ) {
 388                 if ( is_null( $name ) ) {
 389                         return $this->mLBInfo;
 390                 } else {
 391                         if ( array_key_exists( $name, $this->mLBInfo ) ) {
 392                                 return $this->mLBInfo[$name];
 393                         } else {
 394                                 return NULL;
 395                         }
 396                 }
 397         }
 398
 399         function setLBInfo( $name, $value = NULL ) {
 400                 if ( is_null( $value ) ) {
 401                         $this->mLBInfo = $name;
 402                 } else {
 403                         $this->mLBInfo[$name] = $value;
 404                 }
 405         }
 406
 407         /**
 408          * Returns true if this database supports (and uses) cascading deletes
 409          */
 410         function cascadingDeletes() {
 411                 return false;
 412         }
 413
 414         /**
 415          * Returns true if this database supports (and uses) triggers (e.g. on the page table)
 416          */
 417         function cleanupTriggers() {
 418                 return false;
 419         }
 420
 421         /**
 422          * Returns true if this database is strict about what can be put into an IP field.
 423          * Specifically, it uses a NULL value instead of an empty string.
 424          */
 425         function strictIPs() {
 426                 return false;
 427         }
 428
 429         /**
 430          * Returns true if this database uses timestamps rather than integers
 431         */
 432         function realTimestamps() {
 433                 return false;
 434         }
 435
 436         /**
 437          * Returns true if this database does an implicit sort when doing GROUP BY
 438          */
 439         function implicitGroupby() {
 440                 return true;
 441         }
 442
 443         /**
 444          * Returns true if this database can do a native search on IP columns
 445          * e.g. this works as expected: .. WHERE rc_ip = '127.42.12.102/32';
 446          */
 447         function searchableIPs() {
 448                 return false;
 449         }
 450
 451         /**#@+
 452          * Get function
 453          */
 454         function lastQuery() { return $this->mLastQuery; }
 455         function isOpen() { return $this->mOpened; }
 456         /**#@-*/
 457
 458         function setFlag( $flag ) {
 459                 $this->mFlags |= $flag;
 460         }
 461
 462         function clearFlag( $flag ) {
 463                 $this->mFlags &= ~$flag;
 464         }
 465
 466         function getFlag( $flag ) {
 467                 return !!($this->mFlags & $flag);
 468         }
 469
 470         /**
 471          * General read-only accessor
 472          */
 473         function getProperty( $name ) {
 474                 return $this->$name;
 475         }
 476
 477 #------------------------------------------------------------------------------
 478 # Other functions
 479 #------------------------------------------------------------------------------
 480
 481         /**@{{
 482          * Constructor.
 483          * @param string $server database server host
 484          * @param string $user database user name
 485          * @param string $password database user password
 486          * @param string $dbname database name
 487          * @param failFunction
 488          * @param $flags
 489          * @param $tablePrefix String: database table prefixes. By default use the prefix gave in LocalSettings.php
 490          */
 491         function __construct( $server = false, $user = false, $password = false, $dbName = false,
 492                 $failFunction = false, $flags = 0, $tablePrefix = 'get from global' ) {
 493
 494                 global $wgOut, $wgDBprefix, $wgCommandLineMode;
 495                 # Can't get a reference if it hasn't been set yet
 496                 if ( !isset( $wgOut ) ) {
 497                         $wgOut = NULL;
 498                 }
 499                 $this->mOut =& $wgOut;
 500
 501                 $this->mFailFunction = $failFunction;
 502                 $this->mFlags = $flags;
 503
 504                 if ( $this->mFlags & DBO_DEFAULT ) {
 505                         if ( $wgCommandLineMode ) {
 506                                 $this->mFlags &= ~DBO_TRX;
 507                         } else {
 508                                 $this->mFlags |= DBO_TRX;
 509                         }
 510                 }
 511
 512                 /*
 513                 // Faster read-only access
 514                 if ( wfReadOnly() ) {
 515                         $this->mFlags |= DBO_PERSISTENT;
 516                         $this->mFlags &= ~DBO_TRX;
 517                 }*/
 518
 519                 /** Get the default table prefix*/
 520                 if ( $tablePrefix == 'get from global' ) {
 521                         $this->mTablePrefix = $wgDBprefix;
 522                 } else {
 523                         $this->mTablePrefix = $tablePrefix;
 524                 }
 525
 526                 if ( $server ) {
 527                         $this->open( $server, $user, $password, $dbName );
 528                 }
 529         }
 530
 531         /**
 532          * @static
 533          * @param failFunction
 534          * @param $flags
 535          */
 536         static function newFromParams( $server, $user, $password, $dbName, $failFunction = false, $flags = 0 )
 537         {
 538                 return new Database( $server, $user, $password, $dbName, $failFunction, $flags );
 539         }
 540
 541         /**
 542          * Usually aborts on failure
 543          * If the failFunction is set to a non-zero integer, returns success
 544          */
 545         function open( $server, $user, $password, $dbName ) {
 546                 global $wguname;
 547                 wfProfileIn( __METHOD__ );
 548
 549                 # Test for missing mysql.so
 550                 # First try to load it
 551                 if (!@extension_loaded('mysql')) {
 552                         @dl('mysql.so');
 553                 }
 554
 555                 # Fail now
 556                 # Otherwise we get a suppressed fatal error, which is very hard to track down
 557                 if ( !function_exists( 'mysql_connect' ) ) {
 558                         throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
 559                 }
 560
 561                 $this->close();
 562                 $this->mServer = $server;
 563                 $this->mUser = $user;
 564                 $this->mPassword = $password;
 565                 $this->mDBname = $dbName;
 566
 567                 $success = false;
 568
 569                 wfProfileIn("dbconnect-$server");
 570
 571                 # LIVE PATCH by Tim, ask Domas for why: retry loop
 572                 $this->mConn = false;
 573                 $max = 3;
 574                 for ( $i = 0; $i < $max && !$this->mConn; $i++ ) {
 575                         if ( $i > 1 ) {
 576                                 usleep( 1000 );
 577                         }
 578                         if ( $this->mFlags & DBO_PERSISTENT ) {
 579                                 @/**/$this->mConn = mysql_pconnect( $server, $user, $password );
 580                         } else {
 581                                 # Create a new connection...
 582                                 @/**/$this->mConn = mysql_connect( $server, $user, $password, true );
 583                         }
 584                         if ($this->mConn === false) {
 585                                 $iplus = $i + 1;
 586                                 #wfLogDBError("Connect loop error $iplus of $max ($server): " . mysql_errno() . " - " . mysql_error()."\n");
 587                         }
 588                 }
 589
 590                 wfProfileOut("dbconnect-$server");
 591
 592                 if ( $dbName != '' ) {
 593                         if ( $this->mConn !== false ) {
 594                                 $success = @/**/mysql_select_db( $dbName, $this->mConn );
 595                                 if ( !$success ) {
 596                                         $error = "Error selecting database $dbName on server {$this->mServer} " .
 597                                                 "from client host {$wguname['nodename']}\n";
 598                                         wfLogDBError(" Error selecting database $dbName on server {$this->mServer} \n");
 599                                         wfDebug( $error );
 600                                 }
 601                         } else {
 602                                 wfDebug( "DB connection error\n" );
 603                                 wfDebug( "Server: $server, User: $user, Password: " .
 604                                         substr( $password, 0, 3 ) . "..., error: " . mysql_error() . "\n" );
 605                                 $success = false;
 606                         }
 607                 } else {
 608                         # Delay USE query
 609                         $success = (bool)$this->mConn;
 610                 }
 611
 612                 if ( $success ) {
 613                         global $wgDBmysql5;
 614                         if( $wgDBmysql5 ) {
 615                                 // Tell the server we're communicating with it in UTF-8.
 616                                 // This may engage various charset conversions.
 617                                 $this->query( 'SET NAMES utf8' );
 618                         }
 619                 } else {
 620                         $this->reportConnectionError();
 621                 }
 622
 623                 $this->mOpened = $success;
 624                 wfProfileOut( __METHOD__ );
 625                 return $success;
 626         }
 627         /**@}}*/
 628
 629         /**
 630          * Closes a database connection.
 631          * if it is open : commits any open transactions
 632          *
 633          * @return bool operation success. true if already closed.
 634          */
 635         function close()
 636         {
 637                 $this->mOpened = false;
 638                 if ( $this->mConn ) {
 639                         if ( $this->trxLevel() ) {
 640                                 $this->immediateCommit();
 641                         }
 642                         return mysql_close( $this->mConn );
 643                 } else {
 644                         return true;
 645                 }
 646         }
 647
 648         /**
 649          * @param string $error fallback error message, used if none is given by MySQL
 650          */
 651         function reportConnectionError( $error = 'Unknown error' ) {
 652                 $myError = $this->lastError();
 653                 if ( $myError ) {
 654                         $error = $myError;
 655                 }
 656
 657                 if ( $this->mFailFunction ) {
 658                         # Legacy error handling method
 659                         if ( !is_int( $this->mFailFunction ) ) {
 660                                 $ff = $this->mFailFunction;
 661                                 $ff( $this, $error );
 662                         }
 663                 } else {
 664                         # New method
 665                         wfLogDBError( "Connection error: $error\n" );
 666                         throw new DBConnectionError( $this, $error );
 667                 }
 668         }
 669
 670         /**
 671          * Usually aborts on failure.  If errors are explicitly ignored, returns success.
 672          *
 673          * @param  $sql        String: SQL query
 674          * @param  $fname      String: Name of the calling function, for profiling/SHOW PROCESSLIST comment (you can use __METHOD__ or add some extra info)
 675          * @param  $tempIgnore Bool:   Whether to avoid throwing an exception on errors... maybe best to catch the exception instead?
 676          * @return Result object to feed to fetchObject, fetchRow, ...; or false on failure if $tempIgnore set
 677          * @throws DBQueryError Thrown when the database returns an error of any kind
 678          */
 679         public function query( $sql, $fname = '', $tempIgnore = false ) {
 680                 global $wgProfiling;
 681
 682                 if ( $wgProfiling ) {
 683                         # generalizeSQL will probably cut down the query to reasonable
 684                         # logging size most of the time. The substr is really just a sanity check.
 685
 686                         # Who's been wasting my precious column space? -- TS
 687                         #$profName = 'query: ' . $fname . ' ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 688
 689                         if ( is_null( $this->getLBInfo( 'master' ) ) ) {
 690                                 $queryProf = 'query: ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 691                                 $totalProf = 'Database::query';
 692                         } else {
 693                                 $queryProf = 'query-m: ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 694                                 $totalProf = 'Database::query-master';
 695                         }
 696                         wfProfileIn( $totalProf );
 697                         wfProfileIn( $queryProf );
 698                 }
 699
 700                 $this->mLastQuery = $sql;
 701
 702                 # Add a comment for easy SHOW PROCESSLIST interpretation
 703                 if ( $fname ) {
 704                         $commentedSql = preg_replace('/\s/', " /* $fname */ ", $sql, 1);
 705                 } else {
 706                         $commentedSql = $sql;
 707                 }
 708
 709                 # If DBO_TRX is set, start a transaction
 710                 if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() &&
 711                         $sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK'
 712                 ) {
 713                         $this->begin();
 714                 }
 715
 716                 if ( $this->debug() ) {
 717                         $sqlx = substr( $commentedSql, 0, 500 );
 718                         $sqlx = strtr( $sqlx, "\t\n", '  ' );
 719                         wfDebug( "SQL: $sqlx\n" );
 720                 }
 721
 722                 # Do the query and handle errors
 723                 $ret = $this->doQuery( $commentedSql );
 724
 725                 # Try reconnecting if the connection was lost
 726                 if ( false === $ret && ( $this->lastErrno() == 2013 || $this->lastErrno() == 2006 ) ) {
 727                         # Transaction is gone, like it or not
 728                         $this->mTrxLevel = 0;
 729                         wfDebug( "Connection lost, reconnecting...\n" );
 730                         if ( $this->ping() ) {
 731                                 wfDebug( "Reconnected\n" );
 732                                 $sqlx = substr( $commentedSql, 0, 500 );
 733                                 $sqlx = strtr( $sqlx, "\t\n", '  ' );
 734                                 global $wgRequestTime;
 735                                 $elapsed = round( microtime(true) - $wgRequestTime, 3 );
 736                                 wfLogDBError( "Connection lost and reconnected after {$elapsed}s, query: $sqlx\n" );
 737                                 $ret = $this->doQuery( $commentedSql );
 738                         } else {
 739                                 wfDebug( "Failed\n" );
 740                         }
 741                 }
 742
 743                 if ( false === $ret ) {
 744                         $this->reportQueryError( $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore );
 745                 }
 746
 747                 if ( $wgProfiling ) {
 748                         wfProfileOut( $queryProf );
 749                         wfProfileOut( $totalProf );
 750                 }
 751                 return $ret;
 752         }
 753
 754         /**
 755          * The DBMS-dependent part of query()
 756          * @param  $sql String: SQL query.
 757          * @return Result object to feed to fetchObject, fetchRow, ...; or false on failure
 758          * @access private
 759          */
 760         /*private*/ function doQuery( $sql ) {
 761                 if( $this->bufferResults() ) {
 762                         $ret = mysql_query( $sql, $this->mConn );
 763                 } else {
 764                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
 765                 }
 766                 return $ret;
 767         }
 768
 769         /**
 770          * @param $error
 771          * @param $errno
 772          * @param $sql
 773          * @param string $fname
 774          * @param bool $tempIgnore
 775          */
 776         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 777                 global $wgCommandLineMode;
 778                 # Ignore errors during error handling to avoid infinite recursion
 779                 $ignore = $this->ignoreErrors( true );
 780                 ++$this->mErrorCount;
 781
 782                 if( $ignore || $tempIgnore ) {
 783                         wfDebug("SQL ERROR (ignored): $error\n");
 784                         $this->ignoreErrors( $ignore );
 785                 } else {
 786                         $sql1line = str_replace( "\n", "\\n", $sql );
 787                         wfLogDBError("$fname\t{$this->mServer}\t$errno\t$error\t$sql1line\n");
 788                         wfDebug("SQL ERROR: " . $error . "\n");
 789                         throw new DBQueryError( $this, $error, $errno, $sql, $fname );
 790                 }
 791         }
 792
 793
 794         /**
 795          * Intended to be compatible with the PEAR::DB wrapper functions.
 796          * http://pear.php.net/manual/en/package.database.db.intro-execute.php
 797          *
 798          * ? = scalar value, quoted as necessary
 799          * ! = raw SQL bit (a function for instance)
 800          * & = filename; reads the file and inserts as a blob
 801          *     (we don't use this though...)
 802          */
 803         function prepare( $sql, $func = 'Database::prepare' ) {
 804                 /* MySQL doesn't support prepared statements (yet), so just
 805                    pack up the query for reference. We'll manually replace
 806                    the bits later. */
 807                 return array( 'query' => $sql, 'func' => $func );
 808         }
 809
 810         function freePrepared( $prepared ) {
 811                 /* No-op for MySQL */
 812         }
 813
 814         /**
 815          * Execute a prepared query with the various arguments
 816          * @param string $prepared the prepared sql
 817          * @param mixed $args Either an array here, or put scalars as varargs
 818          */
 819         function execute( $prepared, $args = null ) {
 820                 if( !is_array( $args ) ) {
 821                         # Pull the var args
 822                         $args = func_get_args();
 823                         array_shift( $args );
 824                 }
 825                 $sql = $this->fillPrepared( $prepared['query'], $args );
 826                 return $this->query( $sql, $prepared['func'] );
 827         }
 828
 829         /**
 830          * Prepare & execute an SQL statement, quoting and inserting arguments
 831          * in the appropriate places.
 832          * @param string $query
 833          * @param string $args ...
 834          */
 835         function safeQuery( $query, $args = null ) {
 836                 $prepared = $this->prepare( $query, 'Database::safeQuery' );
 837                 if( !is_array( $args ) ) {
 838                         # Pull the var args
 839                         $args = func_get_args();
 840                         array_shift( $args );
 841                 }
 842                 $retval = $this->execute( $prepared, $args );
 843                 $this->freePrepared( $prepared );
 844                 return $retval;
 845         }
 846
 847         /**
 848          * For faking prepared SQL statements on DBs that don't support
 849          * it directly.
 850          * @param string $preparedSql - a 'preparable' SQL statement
 851          * @param array $args - array of arguments to fill it with
 852          * @return string executable SQL
 853          */
 854         function fillPrepared( $preparedQuery, $args ) {
 855                 reset( $args );
 856                 $this->preparedArgs =& $args;
 857                 return preg_replace_callback( '/(\\\\[?!&]|[?!&])/',
 858                         array( &$this, 'fillPreparedArg' ), $preparedQuery );
 859         }
 860
 861         /**
 862          * preg_callback func for fillPrepared()
 863          * The arguments should be in $this->preparedArgs and must not be touched
 864          * while we're doing this.
 865          *
 866          * @param array $matches
 867          * @return string
 868          * @private
 869          */
 870         function fillPreparedArg( $matches ) {
 871                 switch( $matches[1] ) {
 872                         case '\\?': return '?';
 873                         case '\\!': return '!';
 874                         case '\\&': return '&';
 875                 }
 876                 list( /* $n */ , $arg ) = each( $this->preparedArgs );
 877                 switch( $matches[1] ) {
 878                         case '?': return $this->addQuotes( $arg );
 879                         case '!': return $arg;
 880                         case '&':
 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.' );
 883                         default:
 884                                 throw new DBUnexpectedError( $this, 'Received invalid match. This should never happen!' );
 885                 }
 886         }
 887
 888         /**#@+
 889          * @param mixed $res A SQL result
 890          */
 891         /**
 892          * Free a result object
 893          */
 894         function freeResult( $res ) {
 895                 if ( !@/**/mysql_free_result( $res ) ) {
 896                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 897                 }
 898         }
 899
 900         /**
 901          * Fetch the next row from the given result object, in object form.
 902          * Fields can be retrieved with $row->fieldname, with fields acting like
 903          * member variables.
 904          *
 905          * @param $res SQL result object as returned from Database::query(), etc.
 906          * @return MySQL row object
 907          * @throws DBUnexpectedError Thrown if the database returns an error
 908          */
 909         function fetchObject( $res ) {
 910                 @/**/$row = mysql_fetch_object( $res );
 911                 if( $this->lastErrno() ) {
 912                         throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
 913                 }
 914                 return $row;
 915         }
 916
 917         /**
 918          * Fetch the next row from the given result object, in associative array
 919          * form.  Fields are retrieved with $row['fieldname'].
 920          *
 921          * @param $res SQL result object as returned from Database::query(), etc.
 922          * @return MySQL row object
 923          * @throws DBUnexpectedError Thrown if the database returns an error
 924          */
 925         function fetchRow( $res ) {
 926                 @/**/$row = mysql_fetch_array( $res );
 927                 if ( $this->lastErrno() ) {
 928                         throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
 929                 }
 930                 return $row;
 931         }
 932
 933         /**
 934          * Get the number of rows in a result object
 935          */
 936         function numRows( $res ) {
 937                 @/**/$n = mysql_num_rows( $res );
 938                 if( $this->lastErrno() ) {
 939                         throw new DBUnexpectedError( $this, 'Error in numRows(): ' . htmlspecialchars( $this->lastError() ) );
 940                 }
 941                 return $n;
 942         }
 943
 944         /**
 945          * Get the number of fields in a result object
 946          * See documentation for mysql_num_fields()
 947          */
 948         function numFields( $res ) { return mysql_num_fields( $res ); }
 949
 950         /**
 951          * Get a field name in a result object
 952          * See documentation for mysql_field_name():
 953          * http://www.php.net/mysql_field_name
 954          */
 955         function fieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 956
 957         /**
 958          * Get the inserted value of an auto-increment row
 959          *
 960          * The value inserted should be fetched from nextSequenceValue()
 961          *
 962          * Example:
 963          * $id = $dbw->nextSequenceValue('page_page_id_seq');
 964          * $dbw->insert('page',array('page_id' => $id));
 965          * $id = $dbw->insertId();
 966          */
 967         function insertId() { return mysql_insert_id( $this->mConn ); }
 968
 969         /**
 970          * Change the position of the cursor in a result object
 971          * See mysql_data_seek()
 972          */
 973         function dataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 974
 975         /**
 976          * Get the last error number
 977          * See mysql_errno()
 978          */
 979         function lastErrno() {
 980                 if ( $this->mConn ) {
 981                         return mysql_errno( $this->mConn );
 982                 } else {
 983                         return mysql_errno();
 984                 }
 985         }
 986
 987         /**
 988          * Get a description of the last error
 989          * See mysql_error() for more details
 990          */
 991         function lastError() {
 992                 if ( $this->mConn ) {
 993                         # Even if it's non-zero, it can still be invalid
 994                         wfSuppressWarnings();
 995                         $error = mysql_error( $this->mConn );
 996                         if ( !$error ) {
 997                                 $error = mysql_error();
 998                         }
 999                         wfRestoreWarnings();
1000                 } else {
1001                         $error = mysql_error();
1002                 }
1003                 if( $error ) {
1004                         $error .= ' (' . $this->mServer . ')';
1005                 }
1006                 return $error;
1007         }
1008         /**
1009          * Get the number of rows affected by the last write query
1010          * See mysql_affected_rows() for more details
1011          */
1012         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
1013         /**#@-*/ // end of template : @param $result
1014
1015         /**
1016          * Simple UPDATE wrapper
1017          * Usually aborts on failure
1018          * If errors are explicitly ignored, returns success
1019          *
1020          * This function exists for historical reasons, Database::update() has a more standard
1021          * calling convention and feature set
1022          */
1023         function set( $table, $var, $value, $cond, $fname = 'Database::set' )
1024         {
1025                 $table = $this->tableName( $table );
1026                 $sql = "UPDATE $table SET $var = '" .
1027                   $this->strencode( $value ) . "' WHERE ($cond)";
1028                 return (bool)$this->query( $sql, $fname );
1029         }
1030
1031         /**
1032          * Simple SELECT wrapper, returns a single field, input must be encoded
1033          * Usually aborts on failure
1034          * If errors are explicitly ignored, returns FALSE on failure
1035          */
1036         function selectField( $table, $var, $cond='', $fname = 'Database::selectField', $options = array() ) {
1037                 if ( !is_array( $options ) ) {
1038                         $options = array( $options );
1039                 }
1040                 $options['LIMIT'] = 1;
1041
1042                 $res = $this->select( $table, $var, $cond, $fname, $options );
1043                 if ( $res === false || !$this->numRows( $res ) ) {
1044                         return false;
1045                 }
1046                 $row = $this->fetchRow( $res );
1047                 if ( $row !== false ) {
1048                         $this->freeResult( $res );
1049                         return $row[0];
1050                 } else {
1051                         return false;
1052                 }
1053         }
1054
1055         /**
1056          * Returns an optional USE INDEX clause to go after the table, and a
1057          * string to go at the end of the query
1058          *
1059          * @private
1060          *
1061          * @param array $options an associative array of options to be turned into
1062          *              an SQL query, valid keys are listed in the function.
1063          * @return array
1064          */
1065         function makeSelectOptions( $options ) {
1066                 $preLimitTail = $postLimitTail = '';
1067                 $startOpts = '';
1068
1069                 $noKeyOptions = array();
1070                 foreach ( $options as $key => $option ) {
1071                         if ( is_numeric( $key ) ) {
1072                                 $noKeyOptions[$option] = true;
1073                         }
1074                 }
1075
1076                 if ( isset( $options['GROUP BY'] ) ) $preLimitTail .= " GROUP BY {$options['GROUP BY']}";
1077                 if ( isset( $options['ORDER BY'] ) ) $preLimitTail .= " ORDER BY {$options['ORDER BY']}";
1078
1079                 //if (isset($options['LIMIT'])) {
1080                 //      $tailOpts .= $this->limitResult('', $options['LIMIT'],
1081                 //              isset($options['OFFSET']) ? $options['OFFSET']
1082                 //              : false);
1083                 //}
1084
1085                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) $postLimitTail .= ' FOR UPDATE';
1086                 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) $postLimitTail .= ' LOCK IN SHARE MODE';
1087                 if ( isset( $noKeyOptions['DISTINCT'] ) && isset( $noKeyOptions['DISTINCTROW'] ) ) $startOpts .= 'DISTINCT';
1088
1089                 # Various MySQL extensions
1090                 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) $startOpts .= ' /*! STRAIGHT_JOIN */';
1091                 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) $startOpts .= ' HIGH_PRIORITY';
1092                 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) $startOpts .= ' SQL_BIG_RESULT';
1093                 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) $startOpts .= ' SQL_BUFFER_RESULT';
1094                 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) $startOpts .= ' SQL_SMALL_RESULT';
1095                 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) $startOpts .= ' SQL_CALC_FOUND_ROWS';
1096                 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) $startOpts .= ' SQL_CACHE';
1097                 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) $startOpts .= ' SQL_NO_CACHE';
1098
1099                 if ( isset( $options['USE INDEX'] ) && ! is_array( $options['USE INDEX'] ) ) {
1100                         $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1101                 } else {
1102                         $useIndex = '';
1103                 }
1104
1105                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1106         }
1107
1108         /**
1109          * SELECT wrapper
1110          *
1111          * @param mixed  $table   Array or string, table name(s) (prefix auto-added)
1112          * @param mixed  $vars    Array or string, field name(s) to be retrieved
1113          * @param mixed  $conds   Array or string, condition(s) for WHERE
1114          * @param string $fname   Calling function name (use __METHOD__) for logs/profiling
1115          * @param array  $options Associative array of options (e.g. array('GROUP BY' => 'page_title')),
1116          *                        see Database::makeSelectOptions code for list of supported stuff
1117          * @return mixed Database result resource (feed to Database::fetchObject or whatever), or false on failure
1118          */
1119         function select( $table, $vars, $conds='', $fname = 'Database::select', $options = array() )
1120         {
1121                 if( is_array( $vars ) ) {
1122                         $vars = implode( ',', $vars );
1123                 }
1124                 if( !is_array( $options ) ) {
1125                         $options = array( $options );
1126                 }
1127                 if( is_array( $table ) ) {
1128                         if ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1129                                 $from = ' FROM ' . $this->tableNamesWithUseIndex( $table, $options['USE INDEX'] );
1130                         else
1131                                 $from = ' FROM ' . implode( ',', array_map( array( &$this, 'tableName' ), $table ) );
1132                 } elseif ($table!='') {
1133                         if ($table{0}==' ') {
1134                                 $from = ' FROM ' . $table;
1135                         } else {
1136                                 $from = ' FROM ' . $this->tableName( $table );
1137                         }
1138                 } else {
1139                         $from = '';
1140                 }
1141
1142                 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail ) = $this->makeSelectOptions( $options );
1143
1144                 if( !empty( $conds ) ) {
1145                         if ( is_array( $conds ) ) {
1146                                 $conds = $this->makeList( $conds, LIST_AND );
1147                         }
1148                         $sql = "SELECT $startOpts $vars $from $useIndex WHERE $conds $preLimitTail";
1149                 } else {
1150                         $sql = "SELECT $startOpts $vars $from $useIndex $preLimitTail";
1151                 }
1152
1153                 if (isset($options['LIMIT']))
1154                         $sql = $this->limitResult($sql, $options['LIMIT'],
1155                                 isset($options['OFFSET']) ? $options['OFFSET'] : false);
1156                 $sql = "$sql $postLimitTail";
1157
1158                 if (isset($options['EXPLAIN'])) {
1159                         $sql = 'EXPLAIN ' . $sql;
1160                 }
1161
1162                 return $this->query( $sql, $fname );
1163         }
1164
1165         /**
1166          * Single row SELECT wrapper
1167          * Aborts or returns FALSE on error
1168          *
1169          * $vars: the selected variables
1170          * $conds: a condition map, terms are ANDed together.
1171          *   Items with numeric keys are taken to be literal conditions
1172          * Takes an array of selected variables, and a condition map, which is ANDed
1173          * e.g: selectRow( "page", array( "page_id" ), array( "page_namespace" =>
1174          * NS_MAIN, "page_title" => "Astronomy" ) )   would return an object where
1175          * $obj- >page_id is the ID of the Astronomy article
1176          *
1177          * @todo migrate documentation to phpdocumentor format
1178          */
1179         function selectRow( $table, $vars, $conds, $fname = 'Database::selectRow', $options = array() ) {
1180                 $options['LIMIT'] = 1;
1181                 $res = $this->select( $table, $vars, $conds, $fname, $options );
1182                 if ( $res === false )
1183                         return false;
1184                 if ( !$this->numRows($res) ) {
1185                         $this->freeResult($res);
1186                         return false;
1187                 }
1188                 $obj = $this->fetchObject( $res );
1189                 $this->freeResult( $res );
1190                 return $obj;
1191
1192         }
1193
1194         /**
1195          * Estimate rows in dataset
1196          * Returns estimated count, based on EXPLAIN output
1197          * Takes same arguments as Database::select()
1198          */
1199
1200         function estimateRowCount( $table, $vars='*', $conds='', $fname = 'Database::estimateRowCount', $options = array() ) {
1201                 $options['EXPLAIN']=true;
1202                 $res = $this->select ($table, $vars, $conds, $fname, $options );
1203                 if ( $res === false )
1204                         return false;
1205                 if (!$this->numRows($res)) {
1206                         $this->freeResult($res);
1207                         return 0;
1208                 }
1209
1210                 $rows=1;
1211
1212                 while( $plan = $this->fetchObject( $res ) ) {
1213                         $rows *= ($plan->rows > 0)?$plan->rows:1; // avoid resetting to zero
1214                 }
1215
1216                 $this->freeResult($res);
1217                 return $rows;
1218         }
1219
1220
1221         /**
1222          * Removes most variables from an SQL query and replaces them with X or N for numbers.
1223          * It's only slightly flawed. Don't use for anything important.
1224          *
1225          * @param string $sql A SQL Query
1226          * @static
1227          */
1228         static function generalizeSQL( $sql ) {
1229                 # This does the same as the regexp below would do, but in such a way
1230                 # as to avoid crashing php on some large strings.
1231                 # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
1232
1233                 $sql = str_replace ( "\\\\", '', $sql);
1234                 $sql = str_replace ( "\\'", '', $sql);
1235                 $sql = str_replace ( "\\\"", '', $sql);
1236                 $sql = preg_replace ("/'.*'/s", "'X'", $sql);
1237                 $sql = preg_replace ('/".*"/s', "'X'", $sql);
1238
1239                 # All newlines, tabs, etc replaced by single space
1240                 $sql = preg_replace ( '/\s+/', ' ', $sql);
1241
1242                 # All numbers => N
1243                 $sql = preg_replace ('/-?[0-9]+/s', 'N', $sql);
1244
1245                 return $sql;
1246         }
1247
1248         /**
1249          * Determines whether a field exists in a table
1250          * Usually aborts on failure
1251          * If errors are explicitly ignored, returns NULL on failure
1252          */
1253         function fieldExists( $table, $field, $fname = 'Database::fieldExists' ) {
1254                 $table = $this->tableName( $table );
1255                 $res = $this->query( 'DESCRIBE '.$table, $fname );
1256                 if ( !$res ) {
1257                         return NULL;
1258                 }
1259
1260                 $found = false;
1261
1262                 while ( $row = $this->fetchObject( $res ) ) {
1263                         if ( $row->Field == $field ) {
1264                                 $found = true;
1265                                 break;
1266                         }
1267                 }
1268                 return $found;
1269         }
1270
1271         /**
1272          * Determines whether an index exists
1273          * Usually aborts on failure
1274          * If errors are explicitly ignored, returns NULL on failure
1275          */
1276         function indexExists( $table, $index, $fname = 'Database::indexExists' ) {
1277                 $info = $this->indexInfo( $table, $index, $fname );
1278                 if ( is_null( $info ) ) {
1279                         return NULL;
1280                 } else {
1281                         return $info !== false;
1282                 }
1283         }
1284
1285
1286         /**
1287          * Get information about an index into an object
1288          * Returns false if the index does not exist
1289          */
1290         function indexInfo( $table, $index, $fname = 'Database::indexInfo' ) {
1291                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
1292                 # SHOW INDEX should work for 3.x and up:
1293                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
1294                 $table = $this->tableName( $table );
1295                 $sql = 'SHOW INDEX FROM '.$table;
1296                 $res = $this->query( $sql, $fname );
1297                 if ( !$res ) {
1298                         return NULL;
1299                 }
1300
1301                 $result = array();
1302                 while ( $row = $this->fetchObject( $res ) ) {
1303                         if ( $row->Key_name == $index ) {
1304                                 $result[] = $row;
1305                         }
1306                 }
1307                 $this->freeResult($res);
1308
1309                 return empty($result) ? false : $result;
1310         }
1311
1312         /**
1313          * Query whether a given table exists
1314          */
1315         function tableExists( $table ) {
1316                 $table = $this->tableName( $table );
1317                 $old = $this->ignoreErrors( true );
1318                 $res = $this->query( "SELECT 1 FROM $table LIMIT 1" );
1319                 $this->ignoreErrors( $old );
1320                 if( $res ) {
1321                         $this->freeResult( $res );
1322                         return true;
1323                 } else {
1324                         return false;
1325                 }
1326         }
1327
1328         /**
1329          * mysql_fetch_field() wrapper
1330          * Returns false if the field doesn't exist
1331          *
1332          * @param $table
1333          * @param $field
1334          */
1335         function fieldInfo( $table, $field ) {
1336                 $table = $this->tableName( $table );
1337                 $res = $this->query( "SELECT * FROM $table LIMIT 1" );
1338                 $n = mysql_num_fields( $res );
1339                 for( $i = 0; $i < $n; $i++ ) {
1340                         $meta = mysql_fetch_field( $res, $i );
1341                         if( $field == $meta->name ) {
1342                                 return new MySQLField($meta);
1343                         }
1344                 }
1345                 return false;
1346         }
1347
1348         /**
1349          * mysql_field_type() wrapper
1350          */
1351         function fieldType( $res, $index ) {
1352                 return mysql_field_type( $res, $index );
1353         }
1354
1355         /**
1356          * Determines if a given index is unique
1357          */
1358         function indexUnique( $table, $index ) {
1359                 $indexInfo = $this->indexInfo( $table, $index );
1360                 if ( !$indexInfo ) {
1361                         return NULL;
1362                 }
1363                 return !$indexInfo[0]->Non_unique;
1364         }
1365
1366         /**
1367          * INSERT wrapper, inserts an array into a table
1368          *
1369          * $a may be a single associative array, or an array of these with numeric keys, for
1370          * multi-row insert.
1371          *
1372          * Usually aborts on failure
1373          * If errors are explicitly ignored, returns success
1374          */
1375         function insert( $table, $a, $fname = 'Database::insert', $options = array() ) {
1376                 # No rows to insert, easy just return now
1377                 if ( !count( $a ) ) {
1378                         return true;
1379                 }
1380
1381                 $table = $this->tableName( $table );
1382                 if ( !is_array( $options ) ) {
1383                         $options = array( $options );
1384                 }
1385                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1386                         $multi = true;
1387                         $keys = array_keys( $a[0] );
1388                 } else {
1389                         $multi = false;
1390                         $keys = array_keys( $a );
1391                 }
1392
1393                 $sql = 'INSERT ' . implode( ' ', $options ) .
1394                         " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1395
1396                 if ( $multi ) {
1397                         $first = true;
1398                         foreach ( $a as $row ) {
1399                                 if ( $first ) {
1400                                         $first = false;
1401                                 } else {
1402                                         $sql .= ',';
1403                                 }
1404                                 $sql .= '(' . $this->makeList( $row ) . ')';
1405                         }
1406                 } else {
1407                         $sql .= '(' . $this->makeList( $a ) . ')';
1408                 }
1409                 return (bool)$this->query( $sql, $fname );
1410         }
1411
1412         /**
1413          * Make UPDATE options for the Database::update function
1414          *
1415          * @private
1416          * @param array $options The options passed to Database::update
1417          * @return string
1418          */
1419         function makeUpdateOptions( $options ) {
1420                 if( !is_array( $options ) ) {
1421                         $options = array( $options );
1422                 }
1423                 $opts = array();
1424                 if ( in_array( 'LOW_PRIORITY', $options ) )
1425                         $opts[] = $this->lowPriorityOption();
1426                 if ( in_array( 'IGNORE', $options ) )
1427                         $opts[] = 'IGNORE';
1428                 return implode(' ', $opts);
1429         }
1430
1431         /**
1432          * UPDATE wrapper, takes a condition array and a SET array
1433          *
1434          * @param string $table  The table to UPDATE
1435          * @param array  $values An array of values to SET
1436          * @param array  $conds  An array of conditions (WHERE). Use '*' to update all rows.
1437          * @param string $fname  The Class::Function calling this function
1438          *                       (for the log)
1439          * @param array  $options An array of UPDATE options, can be one or
1440          *                        more of IGNORE, LOW_PRIORITY
1441          */
1442         function update( $table, $values, $conds, $fname = 'Database::update', $options = array() ) {
1443                 $table = $this->tableName( $table );
1444                 $opts = $this->makeUpdateOptions( $options );
1445                 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, LIST_SET );
1446                 if ( $conds != '*' ) {
1447                         $sql .= " WHERE " . $this->makeList( $conds, LIST_AND );
1448                 }
1449                 $this->query( $sql, $fname );
1450         }
1451
1452         /**
1453          * Makes an encoded list of strings from an array
1454          * $mode:
1455          *        LIST_COMMA         - comma separated, no field names
1456          *        LIST_AND           - ANDed WHERE clause (without the WHERE)
1457          *        LIST_OR            - ORed WHERE clause (without the WHERE)
1458          *        LIST_SET           - comma separated with field names, like a SET clause
1459          *        LIST_NAMES         - comma separated field names
1460          */
1461         function makeList( $a, $mode = LIST_COMMA ) {
1462                 if ( !is_array( $a ) ) {
1463                         throw new DBUnexpectedError( $this, 'Database::makeList called with incorrect parameters' );
1464                 }
1465
1466                 $first = true;
1467                 $list = '';
1468                 foreach ( $a as $field => $value ) {
1469                         if ( !$first ) {
1470                                 if ( $mode == LIST_AND ) {
1471                                         $list .= ' AND ';
1472                                 } elseif($mode == LIST_OR) {
1473                                         $list .= ' OR ';
1474                                 } else {
1475                                         $list .= ',';
1476                                 }
1477                         } else {
1478                                 $first = false;
1479                         }
1480                         if ( ($mode == LIST_AND || $mode == LIST_OR) && is_numeric( $field ) ) {
1481                                 $list .= "($value)";
1482                         } elseif ( ($mode == LIST_SET) && is_numeric( $field ) ) {
1483                                 $list .= "$value";
1484                         } elseif ( ($mode == LIST_AND || $mode == LIST_OR) && is_array ($value) ) {
1485                                 $list .= $field." IN (".$this->makeList($value).") ";
1486                         } else {
1487                                 if ( $mode == LIST_AND || $mode == LIST_OR || $mode == LIST_SET ) {
1488                                         $list .= "$field = ";
1489                                 }
1490                                 $list .= $mode == LIST_NAMES ? $value : $this->addQuotes( $value );
1491                         }
1492                 }
1493                 return $list;
1494         }
1495
1496         /**
1497          * Change the current database
1498          */
1499         function selectDB( $db ) {
1500                 $this->mDBname = $db;
1501                 return mysql_select_db( $db, $this->mConn );
1502         }
1503
1504         /**
1505          * Format a table name ready for use in constructing an SQL query
1506          *
1507          * This does two important things: it quotes table names which as necessary,
1508          * and it adds a table prefix if there is one.
1509          *
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.
1513          *
1514          * @param string $name database table name
1515          */
1516         function tableName( $name ) {
1517                 global $wgSharedDB;
1518                 # Skip quoted literals
1519                 if ( $name{0} != '`' ) {
1520                         if ( $this->mTablePrefix !== '' &&  strpos( '.', $name ) === false ) {
1521                                 $name = "{$this->mTablePrefix}$name";
1522                         }
1523                         if ( isset( $wgSharedDB ) && "{$this->mTablePrefix}user" == $name ) {
1524                                 $name = "`$wgSharedDB`.`$name`";
1525                         } else {
1526                                 # Standard quoting
1527                                 $name = "`$name`";
1528                         }
1529                 }
1530                 return $name;
1531         }
1532
1533         /**
1534          * Fetch a number of table names into an array
1535          * This is handy when you need to construct SQL for joins
1536          *
1537          * Example:
1538          * extract($dbr->tableNames('user','watchlist'));
1539          * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1540          *         WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1541          */
1542         public function tableNames() {
1543                 $inArray = func_get_args();
1544                 $retVal = array();
1545                 foreach ( $inArray as $name ) {
1546                         $retVal[$name] = $this->tableName( $name );
1547                 }
1548                 return $retVal;
1549         }
1550
1551         /**
1552          * Fetch a number of table names into an zero-indexed numerical array
1553          * This is handy when you need to construct SQL for joins
1554          *
1555          * Example:
1556          * list( $user, $watchlist ) = $dbr->tableNames('user','watchlist');
1557          * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1558          *         WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1559          */
1560         public function tableNamesN() {
1561                 $inArray = func_get_args();
1562                 $retVal = array();
1563                 foreach ( $inArray as $name ) {
1564                         $retVal[] = $this->tableName( $name );
1565                 }
1566                 return $retVal;
1567         }
1568
1569         /**
1570          * @private
1571          */
1572         function tableNamesWithUseIndex( $tables, $use_index ) {
1573                 $ret = array();
1574
1575                 foreach ( $tables as $table )
1576                         if ( @$use_index[$table] !== null )
1577                                 $ret[] = $this->tableName( $table ) . ' ' . $this->useIndexClause( implode( ',', (array)$use_index[$table] ) );
1578                         else
1579                                 $ret[] = $this->tableName( $table );
1580
1581                 return implode( ',', $ret );
1582         }
1583
1584         /**
1585          * Wrapper for addslashes()
1586          * @param string $s String to be slashed.
1587          * @return string slashed string.
1588          */
1589         function strencode( $s ) {
1590                 return mysql_real_escape_string( $s, $this->mConn );
1591         }
1592
1593         /**
1594          * If it's a string, adds quotes and backslashes
1595          * Otherwise returns as-is
1596          */
1597         function addQuotes( $s ) {
1598                 if ( is_null( $s ) ) {
1599                         return 'NULL';
1600                 } else {
1601                         # This will also quote numeric values. This should be harmless,
1602                         # and protects against weird problems that occur when they really
1603                         # _are_ strings such as article titles and string->number->string
1604                         # conversion is not 1:1.
1605                         return "'" . $this->strencode( $s ) . "'";
1606                 }
1607         }
1608
1609         /**
1610          * Escape string for safe LIKE usage
1611          */
1612         function escapeLike( $s ) {
1613                 $s=$this->strencode( $s );
1614                 $s=str_replace(array('%','_'),array('\%','\_'),$s);
1615                 return $s;
1616         }
1617
1618         /**
1619          * Returns an appropriately quoted sequence value for inserting a new row.
1620          * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL
1621          * subclass will return an integer, and save the value for insertId()
1622          */
1623         function nextSequenceValue( $seqName ) {
1624                 return NULL;
1625         }
1626
1627         /**
1628          * USE INDEX clause
1629          * PostgreSQL doesn't have them and returns ""
1630          */
1631         function useIndexClause( $index ) {
1632                 return "FORCE INDEX ($index)";
1633         }
1634
1635         /**
1636          * REPLACE query wrapper
1637          * PostgreSQL simulates this with a DELETE followed by INSERT
1638          * $row is the row to insert, an associative array
1639          * $uniqueIndexes is an array of indexes. Each element may be either a
1640          * field name or an array of field names
1641          *
1642          * It may be more efficient to leave off unique indexes which are unlikely to collide.
1643          * However if you do this, you run the risk of encountering errors which wouldn't have
1644          * occurred in MySQL
1645          *
1646          * @todo migrate comment to phodocumentor format
1647          */
1648         function replace( $table, $uniqueIndexes, $rows, $fname = 'Database::replace' ) {
1649                 $table = $this->tableName( $table );
1650
1651                 # Single row case
1652                 if ( !is_array( reset( $rows ) ) ) {
1653                         $rows = array( $rows );
1654                 }
1655
1656                 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) .') VALUES ';
1657                 $first = true;
1658                 foreach ( $rows as $row ) {
1659                         if ( $first ) {
1660                                 $first = false;
1661                         } else {
1662                                 $sql .= ',';
1663                         }
1664                         $sql .= '(' . $this->makeList( $row ) . ')';
1665                 }
1666                 return $this->query( $sql, $fname );
1667         }
1668
1669         /**
1670          * DELETE where the condition is a join
1671          * MySQL does this with a multi-table DELETE syntax, PostgreSQL does it with sub-selects
1672          *
1673          * For safety, an empty $conds will not delete everything. If you want to delete all rows where the
1674          * join condition matches, set $conds='*'
1675          *
1676          * DO NOT put the join condition in $conds
1677          *
1678          * @param string $delTable The table to delete from.
1679          * @param string $joinTable The other table.
1680          * @param string $delVar The variable to join on, in the first table.
1681          * @param string $joinVar The variable to join on, in the second table.
1682          * @param array $conds Condition array of field names mapped to variables, ANDed together in the WHERE clause
1683          */
1684         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'Database::deleteJoin' ) {
1685                 if ( !$conds ) {
1686                         throw new DBUnexpectedError( $this, 'Database::deleteJoin() called with empty $conds' );
1687                 }
1688
1689                 $delTable = $this->tableName( $delTable );
1690                 $joinTable = $this->tableName( $joinTable );
1691                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1692                 if ( $conds != '*' ) {
1693                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
1694                 }
1695
1696                 return $this->query( $sql, $fname );
1697         }
1698
1699         /**
1700          * Returns the size of a text field, or -1 for "unlimited"
1701          */
1702         function textFieldSize( $table, $field ) {
1703                 $table = $this->tableName( $table );
1704                 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
1705                 $res = $this->query( $sql, 'Database::textFieldSize' );
1706                 $row = $this->fetchObject( $res );
1707                 $this->freeResult( $res );
1708
1709                 $m = array();
1710                 if ( preg_match( '/\((.*)\)/', $row->Type, $m ) ) {
1711                         $size = $m[1];
1712                 } else {
1713                         $size = -1;
1714                 }
1715                 return $size;
1716         }
1717
1718         /**
1719          * @return string Returns the text of the low priority option if it is supported, or a blank string otherwise
1720          */
1721         function lowPriorityOption() {
1722                 return 'LOW_PRIORITY';
1723         }
1724
1725         /**
1726          * DELETE query wrapper
1727          *
1728          * Use $conds == "*" to delete all rows
1729          */
1730         function delete( $table, $conds, $fname = 'Database::delete' ) {
1731                 if ( !$conds ) {
1732                         throw new DBUnexpectedError( $this, 'Database::delete() called with no conditions' );
1733                 }
1734                 $table = $this->tableName( $table );
1735                 $sql = "DELETE FROM $table";
1736                 if ( $conds != '*' ) {
1737                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1738                 }
1739                 return $this->query( $sql, $fname );
1740         }
1741
1742         /**
1743          * INSERT SELECT wrapper
1744          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
1745          * Source items may be literals rather than field names, but strings should be quoted with Database::addQuotes()
1746          * $conds may be "*" to copy the whole table
1747          * srcTable may be an array of tables.
1748          */
1749         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'Database::insertSelect',
1750                 $insertOptions = array(), $selectOptions = array() )
1751         {
1752                 $destTable = $this->tableName( $destTable );
1753                 if ( is_array( $insertOptions ) ) {
1754                         $insertOptions = implode( ' ', $insertOptions );
1755                 }
1756                 if( !is_array( $selectOptions ) ) {
1757                         $selectOptions = array( $selectOptions );
1758                 }
1759                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
1760                 if( is_array( $srcTable ) ) {
1761                         $srcTable =  implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
1762                 } else {
1763                         $srcTable = $this->tableName( $srcTable );
1764                 }
1765                 $sql = "INSERT $insertOptions INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
1766                         " SELECT $startOpts " . implode( ',', $varMap ) .
1767                         " FROM $srcTable $useIndex ";
1768                 if ( $conds != '*' ) {
1769                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1770                 }
1771                 $sql .= " $tailOpts";
1772                 return $this->query( $sql, $fname );
1773         }
1774
1775         /**
1776          * Construct a LIMIT query with optional offset
1777          * This is used for query pages
1778          * $sql string SQL query we will append the limit too
1779          * $limit integer the SQL limit
1780          * $offset integer the SQL offset (default false)
1781          */
1782         function limitResult($sql, $limit, $offset=false) {
1783                 if( !is_numeric($limit) ) {
1784                         throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" );
1785                 }
1786                 return " $sql LIMIT "
1787                                 . ( (is_numeric($offset) && $offset != 0) ? "{$offset}," : "" )
1788                                 . "{$limit} ";
1789         }
1790         function limitResultForUpdate($sql, $num) {
1791                 return $this->limitResult($sql, $num, 0);
1792         }
1793
1794         /**
1795          * Returns an SQL expression for a simple conditional.
1796          * Uses IF on MySQL.
1797          *
1798          * @param string $cond SQL expression which will result in a boolean value
1799          * @param string $trueVal SQL expression to return if true
1800          * @param string $falseVal SQL expression to return if false
1801          * @return string SQL fragment
1802          */
1803         function conditional( $cond, $trueVal, $falseVal ) {
1804                 return " IF($cond, $trueVal, $falseVal) ";
1805         }
1806
1807         /**
1808          * Determines if the last failure was due to a deadlock
1809          */
1810         function wasDeadlock() {
1811                 return $this->lastErrno() == 1213;
1812         }
1813
1814         /**
1815          * Perform a deadlock-prone transaction.
1816          *
1817          * This function invokes a callback function to perform a set of write
1818          * queries. If a deadlock occurs during the processing, the transaction
1819          * will be rolled back and the callback function will be called again.
1820          *
1821          * Usage:
1822          *   $dbw->deadlockLoop( callback, ... );
1823          *
1824          * Extra arguments are passed through to the specified callback function.
1825          *
1826          * Returns whatever the callback function returned on its successful,
1827          * iteration, or false on error, for example if the retry limit was
1828          * reached.
1829          */
1830         function deadlockLoop() {
1831                 $myFname = 'Database::deadlockLoop';
1832
1833                 $this->begin();
1834                 $args = func_get_args();
1835                 $function = array_shift( $args );
1836                 $oldIgnore = $this->ignoreErrors( true );
1837                 $tries = DEADLOCK_TRIES;
1838                 if ( is_array( $function ) ) {
1839                         $fname = $function[0];
1840                 } else {
1841                         $fname = $function;
1842                 }
1843                 do {
1844                         $retVal = call_user_func_array( $function, $args );
1845                         $error = $this->lastError();
1846                         $errno = $this->lastErrno();
1847                         $sql = $this->lastQuery();
1848
1849                         if ( $errno ) {
1850                                 if ( $this->wasDeadlock() ) {
1851                                         # Retry
1852                                         usleep( mt_rand( DEADLOCK_DELAY_MIN, DEADLOCK_DELAY_MAX ) );
1853                                 } else {
1854                                         $this->reportQueryError( $error, $errno, $sql, $fname );
1855                                 }
1856                         }
1857                 } while( $this->wasDeadlock() && --$tries > 0 );
1858                 $this->ignoreErrors( $oldIgnore );
1859                 if ( $tries <= 0 ) {
1860                         $this->query( 'ROLLBACK', $myFname );
1861                         $this->reportQueryError( $error, $errno, $sql, $fname );
1862                         return false;
1863                 } else {
1864                         $this->query( 'COMMIT', $myFname );
1865                         return $retVal;
1866                 }
1867         }
1868
1869         /**
1870          * Do a SELECT MASTER_POS_WAIT()
1871          *
1872          * @param string $file the binlog file
1873          * @param string $pos the binlog position
1874          * @param integer $timeout the maximum number of seconds to wait for synchronisation
1875          */
1876         function masterPosWait( $file, $pos, $timeout ) {
1877                 $fname = 'Database::masterPosWait';
1878                 wfProfileIn( $fname );
1879
1880
1881                 # Commit any open transactions
1882                 $this->immediateCommit();
1883
1884                 # Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
1885                 $encFile = $this->strencode( $file );
1886                 $sql = "SELECT MASTER_POS_WAIT('$encFile', $pos, $timeout)";
1887                 $res = $this->doQuery( $sql );
1888                 if ( $res && $row = $this->fetchRow( $res ) ) {
1889                         $this->freeResult( $res );
1890                         wfProfileOut( $fname );
1891                         return $row[0];
1892                 } else {
1893                         wfProfileOut( $fname );
1894                         return false;
1895                 }
1896         }
1897
1898         /**
1899          * Get the position of the master from SHOW SLAVE STATUS
1900          */
1901         function getSlavePos() {
1902                 $res = $this->query( 'SHOW SLAVE STATUS', 'Database::getSlavePos' );
1903                 $row = $this->fetchObject( $res );
1904                 if ( $row ) {
1905                         return array( $row->Master_Log_File, $row->Read_Master_Log_Pos );
1906                 } else {
1907                         return array( false, false );
1908                 }
1909         }
1910
1911         /**
1912          * Get the position of the master from SHOW MASTER STATUS
1913          */
1914         function getMasterPos() {
1915                 $res = $this->query( 'SHOW MASTER STATUS', 'Database::getMasterPos' );
1916                 $row = $this->fetchObject( $res );
1917                 if ( $row ) {
1918                         return array( $row->File, $row->Position );
1919                 } else {
1920                         return array( false, false );
1921                 }
1922         }
1923
1924         /**
1925          * Begin a transaction, committing any previously open transaction
1926          */
1927         function begin( $fname = 'Database::begin' ) {
1928                 $this->query( 'BEGIN', $fname );
1929                 $this->mTrxLevel = 1;
1930         }
1931
1932         /**
1933          * End a transaction
1934          */
1935         function commit( $fname = 'Database::commit' ) {
1936                 $this->query( 'COMMIT', $fname );
1937                 $this->mTrxLevel = 0;
1938         }
1939
1940         /**
1941          * Rollback a transaction
1942          */
1943         function rollback( $fname = 'Database::rollback' ) {
1944                 $this->query( 'ROLLBACK', $fname );
1945                 $this->mTrxLevel = 0;
1946         }
1947
1948         /**
1949          * Begin a transaction, committing any previously open transaction
1950          * @deprecated use begin()
1951          */
1952         function immediateBegin( $fname = 'Database::immediateBegin' ) {
1953                 $this->begin();
1954         }
1955
1956         /**
1957          * Commit transaction, if one is open
1958          * @deprecated use commit()
1959          */
1960         function immediateCommit( $fname = 'Database::immediateCommit' ) {
1961                 $this->commit();
1962         }
1963
1964         /**
1965          * Return MW-style timestamp used for MySQL schema
1966          */
1967         function timestamp( $ts=0 ) {
1968                 return wfTimestamp(TS_MW,$ts);
1969         }
1970
1971         /**
1972          * Local database timestamp format or null
1973          */
1974         function timestampOrNull( $ts = null ) {
1975                 if( is_null( $ts ) ) {
1976                         return null;
1977                 } else {
1978                         return $this->timestamp( $ts );
1979                 }
1980         }
1981
1982         /**
1983          * @todo document
1984          */
1985         function resultObject( $result ) {
1986                 if( empty( $result ) ) {
1987                         return NULL;
1988                 } else {
1989                         return new ResultWrapper( $this, $result );
1990                 }
1991         }
1992
1993         /**
1994          * Return aggregated value alias
1995          */
1996         function aggregateValue ($valuedata,$valuename='value') {
1997                 return $valuename;
1998         }
1999
2000         /**
2001          * @return string wikitext of a link to the server software's web site
2002          */
2003         function getSoftwareLink() {
2004                 return "[http://www.mysql.com/ MySQL]";
2005         }
2006
2007         /**
2008          * @return string Version information from the database
2009          */
2010         function getServerVersion() {
2011                 return mysql_get_server_info( $this->mConn );
2012         }
2013
2014         /**
2015          * Ping the server and try to reconnect if it there is no connection
2016          */
2017         function ping() {
2018                 if( function_exists( 'mysql_ping' ) ) {
2019                         return mysql_ping( $this->mConn );
2020                 } else {
2021                         wfDebug( "Tried to call mysql_ping but this is ancient PHP version. Faking it!\n" );
2022                         return true;
2023                 }
2024         }
2025
2026         /**
2027          * Get slave lag.
2028          * At the moment, this will only work if the DB user has the PROCESS privilege
2029          */
2030         function getLag() {
2031                 $res = $this->query( 'SHOW PROCESSLIST' );
2032                 # Find slave SQL thread. Assumed to be the second one running, which is a bit
2033                 # dubious, but unfortunately there's no easy rigorous way
2034                 while ( $row = $this->fetchObject( $res ) ) {
2035                         /* This should work for most situations - when default db
2036                          * for thread is not specified, it had no events executed,
2037                          * and therefore it doesn't know yet how lagged it is.
2038                          *
2039                          * Relay log I/O thread does not select databases.
2040                          */
2041                         if ( $row->User == 'system user' &&
2042                                 $row->State != 'Waiting for master to send event' &&
2043                                 $row->State != 'Connecting to master' &&
2044                                 $row->State != 'Queueing master event to the relay log' &&
2045                                 $row->State != 'Waiting for master update' &&
2046                                 $row->State != 'Requesting binlog dump'
2047                                 ) {
2048                                 # This is it, return the time (except -ve)
2049                                 if ( $row->Time > 0x7fffffff ) {
2050                                         return false;
2051                                 } else {
2052                                         return $row->Time;
2053                                 }
2054                         }
2055                 }
2056                 return false;
2057         }
2058
2059         /**
2060          * Get status information from SHOW STATUS in an associative array
2061          */
2062         function getStatus($which="%") {
2063                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
2064                 $status = array();
2065                 while ( $row = $this->fetchObject( $res ) ) {
2066                         $status[$row->Variable_name] = $row->Value;
2067                 }
2068                 return $status;
2069         }
2070
2071         /**
2072          * Return the maximum number of items allowed in a list, or 0 for unlimited.
2073          */
2074         function maxListLen() {
2075                 return 0;
2076         }
2077
2078         function encodeBlob($b) {
2079                 return $b;
2080         }
2081
2082         function decodeBlob($b) {
2083                 return $b;
2084         }
2085
2086         /**
2087          * Override database's default connection timeout.
2088          * May be useful for very long batch queries such as
2089          * full-wiki dumps, where a single query reads out
2090          * over hours or days.
2091          * @param int $timeout in seconds
2092          */
2093         public function setTimeout( $timeout ) {
2094                 $this->query( "SET net_read_timeout=$timeout" );
2095                 $this->query( "SET net_write_timeout=$timeout" );
2096         }
2097
2098         /**
2099          * Read and execute SQL commands from a file.
2100          * Returns true on success, error string on failure
2101          */
2102         function sourceFile( $filename ) {
2103                 $fp = fopen( $filename, 'r' );
2104                 if ( false === $fp ) {
2105                         return "Could not open \"{$filename}\".\n";
2106                 }
2107
2108                 $cmd = "";
2109                 $done = false;
2110                 $dollarquote = false;
2111
2112                 while ( ! feof( $fp ) ) {
2113                         $line = trim( fgets( $fp, 1024 ) );
2114                         $sl = strlen( $line ) - 1;
2115
2116                         if ( $sl < 0 ) { continue; }
2117                         if ( '-' == $line{0} && '-' == $line{1} ) { continue; }
2118
2119                         ## Allow dollar quoting for function declarations
2120                         if (substr($line,0,4) == '$mw$') {
2121                                 if ($dollarquote) {
2122                                         $dollarquote = false;
2123                                         $done = true;
2124                                 }
2125                                 else {
2126                                         $dollarquote = true;
2127                                 }
2128                         }
2129                         else if (!$dollarquote) {
2130                                 if ( ';' == $line{$sl} && ($sl < 2 || ';' != $line{$sl - 1})) {
2131                                         $done = true;
2132                                         $line = substr( $line, 0, $sl );
2133                                 }
2134                         }
2135
2136                         if ( '' != $cmd ) { $cmd .= ' '; }
2137                         $cmd .= "$line\n";
2138
2139                         if ( $done ) {
2140                                 $cmd = str_replace(';;', ";", $cmd);
2141                                 $cmd = $this->replaceVars( $cmd );
2142                                 $res = $this->query( $cmd, 'dbsource', true );
2143
2144                                 if ( false === $res ) {
2145                                         $err = $this->lastError();
2146                                         return "Query \"{$cmd}\" failed with error code \"$err\".\n";
2147                                 }
2148
2149                                 $cmd = '';
2150                                 $done = false;
2151                         }
2152                 }
2153                 fclose( $fp );
2154                 return true;
2155         }
2156
2157         /**
2158          * Replace variables in sourced SQL
2159          */
2160         protected function replaceVars( $ins ) {
2161                 $varnames = array(
2162                         'wgDBserver', 'wgDBname', 'wgDBintlname', 'wgDBuser',
2163                         'wgDBpassword', 'wgDBsqluser', 'wgDBsqlpassword',
2164                         'wgDBadminuser', 'wgDBadminpassword',
2165                 );
2166
2167                 // Ordinary variables
2168                 foreach ( $varnames as $var ) {
2169                         if( isset( $GLOBALS[$var] ) ) {
2170                                 $val = addslashes( $GLOBALS[$var] ); // FIXME: safety check?
2171                                 $ins = str_replace( '{$' . $var . '}', $val, $ins );
2172                                 $ins = str_replace( '/*$' . $var . '*/`', '`' . $val, $ins );
2173                                 $ins = str_replace( '/*$' . $var . '*/', $val, $ins );
2174                         }
2175                 }
2176
2177                 // Table prefixes
2178                 $ins = preg_replace_callback( '/\/\*(?:\$wgDBprefix|_)\*\/([a-z_]*)/',
2179                         array( &$this, 'tableNameCallback' ), $ins );
2180                 return $ins;
2181         }
2182
2183         /**
2184          * Table name callback
2185          * @private
2186          */
2187         protected function tableNameCallback( $matches ) {
2188                 return $this->tableName( $matches[1] );
2189         }
2190
2191 }
2192
2193 /**
2194  * Database abstraction object for mySQL
2195  * Inherit all methods and properties of Database::Database()
2196  *
2197  * @addtogroup Database
2198  * @see Database
2199  */
2200 class DatabaseMysql extends Database {
2201         # Inherit all
2202 }
2203
2204
2205 /**
2206  * Result wrapper for grabbing data queried by someone else
2207  * @addtogroup Database
2208  */
2209 class ResultWrapper {
2210         var $db, $result;
2211
2212         /**
2213          * @todo document
2214          */
2215         function ResultWrapper( &$database, $result ) {
2216                 $this->db =& $database;
2217                 $this->result =& $result;
2218         }
2219
2220         /**
2221          * @todo document
2222          */
2223         function numRows() {
2224                 return $this->db->numRows( $this->result );
2225         }
2226
2227         /**
2228          * @todo document
2229          */
2230         function fetchObject() {
2231                 return $this->db->fetchObject( $this->result );
2232         }
2233
2234         /**
2235          * @todo document
2236          */
2237         function fetchRow() {
2238                 return $this->db->fetchRow( $this->result );
2239         }
2240
2241         /**
2242          * @todo document
2243          */
2244         function free() {
2245                 $this->db->freeResult( $this->result );
2246                 unset( $this->result );
2247                 unset( $this->db );
2248         }
2249
2250         function seek( $row ) {
2251                 $this->db->dataSeek( $this->result, $row );
2252         }
2253
2254         function rewind() {
2255                 if ($this->numRows()) {
2256                         $this->db->dataSeek($this->result, 0);
2257                 }
2258         }
2259
2260 }
2261
2262 ?>