includes/db/DatabaseSqlite.php

   1 <?php
   2 /**
   3  * This is the SQLite database abstraction layer.
   4  * See maintenance/sqlite/README for development notes and other specific information
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  * http://www.gnu.org/copyleft/gpl.html
  20  *
  21  * @file
  22  * @ingroup Database
  23  */
  24
  25 /**
  26  * @ingroup Database
  27  */
  28 class DatabaseSqlite extends DatabaseBase {
  29
  30         private static $fulltextEnabled = null;
  31
  32         var $mAffectedRows;
  33         var $mLastResult;
  34         var $mDatabaseFile;
  35         var $mName;
  36
  37         /**
  38          * @var PDO
  39          */
  40         protected $mConn;
  41
  42         /**
  43          * Constructor.
  44          * Parameters $server, $user and $password are not used.
  45          * @param $server string
  46          * @param $user string
  47          * @param $password string
  48          * @param $dbName string
  49          * @param $flags int
  50          */
  51         function __construct( $server = false, $user = false, $password = false, $dbName = false, $flags = 0 ) {
  52                 $this->mName = $dbName;
  53                 parent::__construct( $server, $user, $password, $dbName, $flags );
  54                 // parent doesn't open when $user is false, but we can work with $dbName
  55                 if( $dbName ) {
  56                         global $wgSharedDB;
  57                         if( $this->open( $server, $user, $password, $dbName ) && $wgSharedDB ) {
  58                                 $this->attachDatabase( $wgSharedDB );
  59                         }
  60                 }
  61         }
  62
  63         /**
  64          * @return string
  65          */
  66         function getType() {
  67                 return 'sqlite';
  68         }
  69
  70         /**
  71          * @todo: check if it should be true like parent class
  72          *
  73          * @return bool
  74          */
  75         function implicitGroupby() {
  76                 return false;
  77         }
  78
  79         /** Open an SQLite database and return a resource handle to it
  80          *  NOTE: only $dbName is used, the other parameters are irrelevant for SQLite databases
  81          *
  82          * @param string $server
  83          * @param string $user
  84          * @param string $pass
  85          * @param string $dbName
  86          *
  87          * @throws DBConnectionError
  88          * @return PDO
  89          */
  90         function open( $server, $user, $pass, $dbName ) {
  91                 global $wgSQLiteDataDir;
  92
  93                 $fileName = self::generateFileName( $wgSQLiteDataDir, $dbName );
  94                 if ( !is_readable( $fileName ) ) {
  95                         $this->mConn = false;
  96                         throw new DBConnectionError( $this, "SQLite database not accessible" );
  97                 }
  98                 $this->openFile( $fileName );
  99                 return $this->mConn;
 100         }
 101
 102         /**
 103          * Opens a database file
 104          *
 105          * @param $fileName string
 106          *
 107          * @throws DBConnectionError
 108          * @return PDO|bool SQL connection or false if failed
 109          */
 110         function openFile( $fileName ) {
 111                 $this->mDatabaseFile = $fileName;
 112                 try {
 113                         if ( $this->mFlags & DBO_PERSISTENT ) {
 114                                 $this->mConn = new PDO( "sqlite:$fileName", '', '',
 115                                         array( PDO::ATTR_PERSISTENT => true ) );
 116                         } else {
 117                                 $this->mConn = new PDO( "sqlite:$fileName", '', '' );
 118                         }
 119                 } catch ( PDOException $e ) {
 120                         $err = $e->getMessage();
 121                 }
 122                 if ( !$this->mConn ) {
 123                         wfDebug( "DB connection error: $err\n" );
 124                         throw new DBConnectionError( $this, $err );
 125                 }
 126                 $this->mOpened = !!$this->mConn;
 127                 # set error codes only, don't raise exceptions
 128                 if ( $this->mOpened ) {
 129                         $this->mConn->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_SILENT );
 130                         return true;
 131                 }
 132         }
 133
 134         /**
 135          * Does not actually close the connection, just destroys the reference for GC to do its work
 136          * @return bool
 137          */
 138         protected function closeConnection() {
 139                 $this->mConn = null;
 140                 return true;
 141         }
 142
 143         /**
 144          * Generates a database file name. Explicitly public for installer.
 145          * @param $dir String: Directory where database resides
 146          * @param $dbName String: Database name
 147          * @return String
 148          */
 149         public static function generateFileName( $dir, $dbName ) {
 150                 return "$dir/$dbName.sqlite";
 151         }
 152
 153         /**
 154          * Check if the searchindext table is FTS enabled.
 155          * @return bool False if not enabled.
 156          */
 157         function checkForEnabledSearch() {
 158                 if ( self::$fulltextEnabled === null ) {
 159                         self::$fulltextEnabled = false;
 160                         $table = $this->tableName( 'searchindex' );
 161                         $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name = '$table'", __METHOD__ );
 162                         if ( $res ) {
 163                                 $row = $res->fetchRow();
 164                                 self::$fulltextEnabled = stristr($row['sql'], 'fts' ) !== false;
 165                         }
 166                 }
 167                 return self::$fulltextEnabled;
 168         }
 169
 170         /**
 171          * Returns version of currently supported SQLite fulltext search module or false if none present.
 172          * @return String
 173          */
 174         static function getFulltextSearchModule() {
 175                 static $cachedResult = null;
 176                 if ( $cachedResult !== null ) {
 177                         return $cachedResult;
 178                 }
 179                 $cachedResult = false;
 180                 $table = 'dummy_search_test';
 181
 182                 $db = new DatabaseSqliteStandalone( ':memory:' );
 183
 184                 if ( $db->query( "CREATE VIRTUAL TABLE $table USING FTS3(dummy_field)", __METHOD__, true ) ) {
 185                         $cachedResult = 'FTS3';
 186                 }
 187                 $db->close();
 188                 return $cachedResult;
 189         }
 190
 191         /**
 192          * Attaches external database to our connection, see http://sqlite.org/lang_attach.html
 193          * for details.
 194          *
 195          * @param $name String: database name to be used in queries like SELECT foo FROM dbname.table
 196          * @param $file String: database file name. If omitted, will be generated using $name and $wgSQLiteDataDir
 197          * @param $fname String: calling function name
 198          *
 199          * @return ResultWrapper
 200          */
 201         function attachDatabase( $name, $file = false, $fname = 'DatabaseSqlite::attachDatabase' ) {
 202                 global $wgSQLiteDataDir;
 203                 if ( !$file ) {
 204                         $file = self::generateFileName( $wgSQLiteDataDir, $name );
 205                 }
 206                 $file = $this->addQuotes( $file );
 207                 return $this->query( "ATTACH DATABASE $file AS $name", $fname );
 208         }
 209
 210         /**
 211          * @see DatabaseBase::isWriteQuery()
 212          *
 213          * @param $sql string
 214          *
 215          * @return bool
 216          */
 217         function isWriteQuery( $sql ) {
 218                 return parent::isWriteQuery( $sql ) && !preg_match( '/^ATTACH\b/i', $sql );
 219         }
 220
 221         /**
 222          * SQLite doesn't allow buffered results or data seeking etc, so we'll use fetchAll as the result
 223          *
 224          * @param $sql string
 225          *
 226          * @return ResultWrapper
 227          */
 228         protected function doQuery( $sql ) {
 229                 $res = $this->mConn->query( $sql );
 230                 if ( $res === false ) {
 231                         return false;
 232                 } else {
 233                         $r = $res instanceof ResultWrapper ? $res->result : $res;
 234                         $this->mAffectedRows = $r->rowCount();
 235                         $res = new ResultWrapper( $this, $r->fetchAll() );
 236                 }
 237                 return $res;
 238         }
 239
 240         /**
 241          * @param $res ResultWrapper
 242          */
 243         function freeResult( $res ) {
 244                 if ( $res instanceof ResultWrapper ) {
 245                         $res->result = null;
 246                 } else {
 247                         $res = null;
 248                 }
 249         }
 250
 251         /**
 252          * @param $res ResultWrapper
 253          * @return
 254          */
 255         function fetchObject( $res ) {
 256                 if ( $res instanceof ResultWrapper ) {
 257                         $r =& $res->result;
 258                 } else {
 259                         $r =& $res;
 260                 }
 261
 262                 $cur = current( $r );
 263                 if ( is_array( $cur ) ) {
 264                         next( $r );
 265                         $obj = new stdClass;
 266                         foreach ( $cur as $k => $v ) {
 267                                 if ( !is_numeric( $k ) ) {
 268                                         $obj->$k = $v;
 269                                 }
 270                         }
 271
 272                         return $obj;
 273                 }
 274                 return false;
 275         }
 276
 277         /**
 278          * @param $res ResultWrapper
 279          * @return bool|mixed
 280          */
 281         function fetchRow( $res ) {
 282                 if ( $res instanceof ResultWrapper ) {
 283                         $r =& $res->result;
 284                 } else {
 285                         $r =& $res;
 286                 }
 287                 $cur = current( $r );
 288                 if ( is_array( $cur ) ) {
 289                         next( $r );
 290                         return $cur;
 291                 }
 292                 return false;
 293         }
 294
 295         /**
 296          * The PDO::Statement class implements the array interface so count() will work
 297          *
 298          * @param $res ResultWrapper
 299          *
 300          * @return int
 301          */
 302         function numRows( $res ) {
 303                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 304                 return count( $r );
 305         }
 306
 307         /**
 308          * @param $res ResultWrapper
 309          * @return int
 310          */
 311         function numFields( $res ) {
 312                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 313                 return is_array( $r ) ? count( $r[0] ) : 0;
 314         }
 315
 316         /**
 317          * @param $res ResultWrapper
 318          * @param $n
 319          * @return bool
 320          */
 321         function fieldName( $res, $n ) {
 322                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 323                 if ( is_array( $r ) ) {
 324                         $keys = array_keys( $r[0] );
 325                         return $keys[$n];
 326                 }
 327                 return false;
 328         }
 329
 330         /**
 331          * Use MySQL's naming (accounts for prefix etc) but remove surrounding backticks
 332          *
 333          * @param $name
 334          * @param $format String
 335          * @return string
 336          */
 337         function tableName( $name, $format = 'quoted' ) {
 338                 // table names starting with sqlite_ are reserved
 339                 if ( strpos( $name, 'sqlite_' ) === 0 ) {
 340                         return $name;
 341                 }
 342                 return str_replace( '"', '', parent::tableName( $name, $format ) );
 343         }
 344
 345         /**
 346          * Index names have DB scope
 347          *
 348          * @param $index string
 349          *
 350          * @return string
 351          */
 352         function indexName( $index ) {
 353                 return $index;
 354         }
 355
 356         /**
 357          * This must be called after nextSequenceVal
 358          *
 359          * @return int
 360          */
 361         function insertId() {
 362                 // PDO::lastInsertId yields a string :(
 363                 return intval( $this->mConn->lastInsertId() );
 364         }
 365
 366         /**
 367          * @param $res ResultWrapper
 368          * @param $row
 369          */
 370         function dataSeek( $res, $row ) {
 371                 if ( $res instanceof ResultWrapper ) {
 372                         $r =& $res->result;
 373                 } else {
 374                         $r =& $res;
 375                 }
 376                 reset( $r );
 377                 if ( $row > 0 ) {
 378                         for ( $i = 0; $i < $row; $i++ ) {
 379                                 next( $r );
 380                         }
 381                 }
 382         }
 383
 384         /**
 385          * @return string
 386          */
 387         function lastError() {
 388                 if ( !is_object( $this->mConn ) ) {
 389                         return "Cannot return last error, no db connection";
 390                 }
 391                 $e = $this->mConn->errorInfo();
 392                 return isset( $e[2] ) ? $e[2] : '';
 393         }
 394
 395         /**
 396          * @return string
 397          */
 398         function lastErrno() {
 399                 if ( !is_object( $this->mConn ) ) {
 400                         return "Cannot return last error, no db connection";
 401                 } else {
 402                         $info = $this->mConn->errorInfo();
 403                         return $info[1];
 404                 }
 405         }
 406
 407         /**
 408          * @return int
 409          */
 410         function affectedRows() {
 411                 return $this->mAffectedRows;
 412         }
 413
 414         /**
 415          * Returns information about an index
 416          * Returns false if the index does not exist
 417          * - if errors are explicitly ignored, returns NULL on failure
 418          *
 419          * @return array
 420          */
 421         function indexInfo( $table, $index, $fname = 'DatabaseSqlite::indexExists' ) {
 422                 $sql = 'PRAGMA index_info(' . $this->addQuotes( $this->indexName( $index ) ) . ')';
 423                 $res = $this->query( $sql, $fname );
 424                 if ( !$res ) {
 425                         return null;
 426                 }
 427                 if ( $res->numRows() == 0 ) {
 428                         return false;
 429                 }
 430                 $info = array();
 431                 foreach ( $res as $row ) {
 432                         $info[] = $row->name;
 433                 }
 434                 return $info;
 435         }
 436
 437         /**
 438          * @param $table
 439          * @param $index
 440          * @param $fname string
 441          * @return bool|null
 442          */
 443         function indexUnique( $table, $index, $fname = 'DatabaseSqlite::indexUnique' ) {
 444                 $row = $this->selectRow( 'sqlite_master', '*',
 445                         array(
 446                                 'type' => 'index',
 447                                 'name' => $this->indexName( $index ),
 448                         ), $fname );
 449                 if ( !$row || !isset( $row->sql ) ) {
 450                         return null;
 451                 }
 452
 453                 // $row->sql will be of the form CREATE [UNIQUE] INDEX ...
 454                 $indexPos = strpos( $row->sql, 'INDEX' );
 455                 if ( $indexPos === false ) {
 456                         return null;
 457                 }
 458                 $firstPart = substr( $row->sql, 0, $indexPos );
 459                 $options = explode( ' ', $firstPart );
 460                 return in_array( 'UNIQUE', $options );
 461         }
 462
 463         /**
 464          * Filter the options used in SELECT statements
 465          *
 466          * @param $options array
 467          *
 468          * @return array
 469          */
 470         function makeSelectOptions( $options ) {
 471                 foreach ( $options as $k => $v ) {
 472                         if ( is_numeric( $k ) && $v == 'FOR UPDATE' ) {
 473                                 $options[$k] = '';
 474                         }
 475                 }
 476                 return parent::makeSelectOptions( $options );
 477         }
 478
 479         /**
 480          * @param $options array
 481          * @return string
 482          */
 483         function makeUpdateOptions( $options ) {
 484                 $options = self::fixIgnore( $options );
 485                 return parent::makeUpdateOptions( $options );
 486         }
 487
 488         /**
 489          * @param $options array
 490          * @return array
 491          */
 492         static function fixIgnore( $options ) {
 493                 # SQLite uses OR IGNORE not just IGNORE
 494                 foreach ( $options as $k => $v ) {
 495                         if ( $v == 'IGNORE' ) {
 496                                 $options[$k] = 'OR IGNORE';
 497                         }
 498                 }
 499                 return $options;
 500         }
 501
 502         /**
 503          * @param $options array
 504          * @return string
 505          */
 506         function makeInsertOptions( $options ) {
 507                 $options = self::fixIgnore( $options );
 508                 return parent::makeInsertOptions( $options );
 509         }
 510
 511         /**
 512          * Based on generic method (parent) with some prior SQLite-sepcific adjustments
 513          * @return bool
 514          */
 515         function insert( $table, $a, $fname = 'DatabaseSqlite::insert', $options = array() ) {
 516                 if ( !count( $a ) ) {
 517                         return true;
 518                 }
 519
 520                 # SQLite can't handle multi-row inserts, so divide up into multiple single-row inserts
 521                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
 522                         $ret = true;
 523                         foreach ( $a as $v ) {
 524                                 if ( !parent::insert( $table, $v, "$fname/multi-row", $options ) ) {
 525                                         $ret = false;
 526                                 }
 527                         }
 528                 } else {
 529                         $ret = parent::insert( $table, $a, "$fname/single-row", $options );
 530                 }
 531
 532                 return $ret;
 533         }
 534
 535         /**
 536          * @param $table
 537          * @param $uniqueIndexes
 538          * @param $rows
 539          * @param $fname string
 540          * @return bool|ResultWrapper
 541          */
 542         function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseSqlite::replace' ) {
 543                 if ( !count( $rows ) ) return true;
 544
 545                 # SQLite can't handle multi-row replaces, so divide up into multiple single-row queries
 546                 if ( isset( $rows[0] ) && is_array( $rows[0] ) ) {
 547                         $ret = true;
 548                         foreach ( $rows as $v ) {
 549                                 if ( !$this->nativeReplace( $table, $v, "$fname/multi-row" ) ) {
 550                                         $ret = false;
 551                                 }
 552                         }
 553                 } else {
 554                         $ret = $this->nativeReplace( $table, $rows, "$fname/single-row" );
 555                 }
 556
 557                 return $ret;
 558         }
 559
 560         /**
 561          * Returns the size of a text field, or -1 for "unlimited"
 562          * In SQLite this is SQLITE_MAX_LENGTH, by default 1GB. No way to query it though.
 563          *
 564          * @return int
 565          */
 566         function textFieldSize( $table, $field ) {
 567                 return -1;
 568         }
 569
 570         /**
 571          * @return bool
 572          */
 573         function unionSupportsOrderAndLimit() {
 574                 return false;
 575         }
 576
 577         /**
 578          * @param $sqls
 579          * @param $all
 580          * @return string
 581          */
 582         function unionQueries( $sqls, $all ) {
 583                 $glue = $all ? ' UNION ALL ' : ' UNION ';
 584                 return implode( $glue, $sqls );
 585         }
 586
 587         /**
 588          * @return bool
 589          */
 590         function wasDeadlock() {
 591                 return $this->lastErrno() == 5; // SQLITE_BUSY
 592         }
 593
 594         /**
 595          * @return bool
 596          */
 597         function wasErrorReissuable() {
 598                 return $this->lastErrno() ==  17; // SQLITE_SCHEMA;
 599         }
 600
 601         /**
 602          * @return bool
 603          */
 604         function wasReadOnlyError() {
 605                 return $this->lastErrno() == 8; // SQLITE_READONLY;
 606         }
 607
 608         /**
 609          * @return string wikitext of a link to the server software's web site
 610          */
 611         public static function getSoftwareLink() {
 612                 return "[http://sqlite.org/ SQLite]";
 613         }
 614
 615         /**
 616          * @return string Version information from the database
 617          */
 618         function getServerVersion() {
 619                 $ver = $this->mConn->getAttribute( PDO::ATTR_SERVER_VERSION );
 620                 return $ver;
 621         }
 622
 623         /**
 624          * @return string User-friendly database information
 625          */
 626         public function getServerInfo() {
 627                 return wfMessage( self::getFulltextSearchModule() ? 'sqlite-has-fts' : 'sqlite-no-fts', $this->getServerVersion() )->text();
 628         }
 629
 630         /**
 631          * Get information about a given field
 632          * Returns false if the field does not exist.
 633          *
 634          * @param $table string
 635          * @param $field string
 636          * @return SQLiteField|bool False on failure
 637          */
 638         function fieldInfo( $table, $field ) {
 639                 $tableName = $this->tableName( $table );
 640                 $sql = 'PRAGMA table_info(' . $this->addQuotes( $tableName ) . ')';
 641                 $res = $this->query( $sql, __METHOD__ );
 642                 foreach ( $res as $row ) {
 643                         if ( $row->name == $field ) {
 644                                 return new SQLiteField( $row, $tableName );
 645                         }
 646                 }
 647                 return false;
 648         }
 649
 650         protected function doBegin( $fname = '' ) {
 651                 if ( $this->mTrxLevel == 1 ) {
 652                         $this->commit( __METHOD__ );
 653                 }
 654                 $this->mConn->beginTransaction();
 655                 $this->mTrxLevel = 1;
 656         }
 657
 658         protected function doCommit( $fname = '' ) {
 659                 if ( $this->mTrxLevel == 0 ) {
 660                         return;
 661                 }
 662                 $this->mConn->commit();
 663                 $this->mTrxLevel = 0;
 664         }
 665
 666         protected function doRollback( $fname = '' ) {
 667                 if ( $this->mTrxLevel == 0 ) {
 668                         return;
 669                 }
 670                 $this->mConn->rollBack();
 671                 $this->mTrxLevel = 0;
 672         }
 673
 674         /**
 675          * @param $s string
 676          * @return string
 677          */
 678         function strencode( $s ) {
 679                 return substr( $this->addQuotes( $s ), 1, - 1 );
 680         }
 681
 682         /**
 683          * @param $b
 684          * @return Blob
 685          */
 686         function encodeBlob( $b ) {
 687                 return new Blob( $b );
 688         }
 689
 690         /**
 691          * @param $b Blob|string
 692          * @return string
 693          */
 694         function decodeBlob( $b ) {
 695                 if ( $b instanceof Blob ) {
 696                         $b = $b->fetch();
 697                 }
 698                 return $b;
 699         }
 700
 701         /**
 702          * @param $s Blob|string
 703          * @return string
 704          */
 705         function addQuotes( $s ) {
 706                 if ( $s instanceof Blob ) {
 707                         return "x'" . bin2hex( $s->fetch() ) . "'";
 708                 } else {
 709                         return $this->mConn->quote( $s );
 710                 }
 711         }
 712
 713         /**
 714          * @return string
 715          */
 716         function buildLike() {
 717                 $params = func_get_args();
 718                 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
 719                         $params = $params[0];
 720                 }
 721                 return parent::buildLike( $params ) . "ESCAPE '\' ";
 722         }
 723
 724         /**
 725          * @return string
 726          */
 727         public function getSearchEngine() {
 728                 return "SearchSqlite";
 729         }
 730
 731         /**
 732          * No-op version of deadlockLoop
 733          * @return mixed
 734          */
 735         public function deadlockLoop( /*...*/ ) {
 736                 $args = func_get_args();
 737                 $function = array_shift( $args );
 738                 return call_user_func_array( $function, $args );
 739         }
 740
 741         /**
 742          * @param $s string
 743          * @return string
 744          */
 745         protected function replaceVars( $s ) {
 746                 $s = parent::replaceVars( $s );
 747                 if ( preg_match( '/^\s*(CREATE|ALTER) TABLE/i', $s ) ) {
 748                         // CREATE TABLE hacks to allow schema file sharing with MySQL
 749
 750                         // binary/varbinary column type -> blob
 751                         $s = preg_replace( '/\b(var)?binary(\(\d+\))/i', 'BLOB', $s );
 752                         // no such thing as unsigned
 753                         $s = preg_replace( '/\b(un)?signed\b/i', '', $s );
 754                         // INT -> INTEGER
 755                         $s = preg_replace( '/\b(tiny|small|medium|big|)int(\s*\(\s*\d+\s*\)|\b)/i', 'INTEGER', $s );
 756                         // floating point types -> REAL
 757                         $s = preg_replace( '/\b(float|double(\s+precision)?)(\s*\(\s*\d+\s*(,\s*\d+\s*)?\)|\b)/i', 'REAL', $s );
 758                         // varchar -> TEXT
 759                         $s = preg_replace( '/\b(var)?char\s*\(.*?\)/i', 'TEXT', $s );
 760                         // TEXT normalization
 761                         $s = preg_replace( '/\b(tiny|medium|long)text\b/i', 'TEXT', $s );
 762                         // BLOB normalization
 763                         $s = preg_replace( '/\b(tiny|small|medium|long|)blob\b/i', 'BLOB', $s );
 764                         // BOOL -> INTEGER
 765                         $s = preg_replace( '/\bbool(ean)?\b/i', 'INTEGER', $s );
 766                         // DATETIME -> TEXT
 767                         $s = preg_replace( '/\b(datetime|timestamp)\b/i', 'TEXT', $s );
 768                         // No ENUM type
 769                         $s = preg_replace( '/\benum\s*\([^)]*\)/i', 'TEXT', $s );
 770                         // binary collation type -> nothing
 771                         $s = preg_replace( '/\bbinary\b/i', '', $s );
 772                         // auto_increment -> autoincrement
 773                         $s = preg_replace( '/\bauto_increment\b/i', 'AUTOINCREMENT', $s );
 774                         // No explicit options
 775                         $s = preg_replace( '/\)[^);]*(;?)\s*$/', ')\1', $s );
 776                         // AUTOINCREMENT should immedidately follow PRIMARY KEY
 777                         $s = preg_replace( '/primary key (.*?) autoincrement/i', 'PRIMARY KEY AUTOINCREMENT $1', $s );
 778                 } elseif ( preg_match( '/^\s*CREATE (\s*(?:UNIQUE|FULLTEXT)\s+)?INDEX/i', $s ) ) {
 779                         // No truncated indexes
 780                         $s = preg_replace( '/\(\d+\)/', '', $s );
 781                         // No FULLTEXT
 782                         $s = preg_replace( '/\bfulltext\b/i', '', $s );
 783                 }
 784                 return $s;
 785         }
 786
 787         /**
 788          * Build a concatenation list to feed into a SQL query
 789          *
 790          * @param $stringList array
 791          *
 792          * @return string
 793          */
 794         function buildConcat( $stringList ) {
 795                 return '(' . implode( ') || (', $stringList ) . ')';
 796         }
 797
 798         /**
 799          * @throws MWException
 800          * @param $oldName
 801          * @param $newName
 802          * @param $temporary bool
 803          * @param $fname string
 804          * @return bool|ResultWrapper
 805          */
 806         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabaseSqlite::duplicateTableStructure' ) {
 807                 $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name=" . $this->addQuotes( $oldName ) . " AND type='table'", $fname );
 808                 $obj = $this->fetchObject( $res );
 809                 if ( !$obj ) {
 810                         throw new MWException( "Couldn't retrieve structure for table $oldName" );
 811                 }
 812                 $sql = $obj->sql;
 813                 $sql = preg_replace( '/(?<=\W)"?' . preg_quote( trim( $this->addIdentifierQuotes( $oldName ), '"' ) ) . '"?(?=\W)/', $this->addIdentifierQuotes( $newName ), $sql, 1 );
 814                 if ( $temporary ) {
 815                         if ( preg_match( '/^\\s*CREATE\\s+VIRTUAL\\s+TABLE\b/i', $sql ) ) {
 816                                 wfDebug( "Table $oldName is virtual, can't create a temporary duplicate.\n" );
 817                         } else {
 818                                 $sql = str_replace( 'CREATE TABLE', 'CREATE TEMPORARY TABLE', $sql );
 819                         }
 820                 }
 821                 return $this->query( $sql, $fname );
 822         }
 823
 824
 825         /**
 826          * List all tables on the database
 827          *
 828          * @param $prefix string Only show tables with this prefix, e.g. mw_
 829          * @param $fname String: calling function name
 830          *
 831          * @return array
 832          */
 833         function listTables( $prefix = null, $fname = 'DatabaseSqlite::listTables' ) {
 834                 $result = $this->select(
 835                         'sqlite_master',
 836                         'name',
 837                         "type='table'"
 838                 );
 839
 840                 $endArray = array();
 841
 842                 foreach( $result as $table ) {
 843                         $vars = get_object_vars($table);
 844                         $table = array_pop( $vars );
 845
 846                         if( !$prefix || strpos( $table, $prefix ) === 0 ) {
 847                                 if ( strpos( $table, 'sqlite_' ) !== 0 ) {
 848                                         $endArray[] = $table;
 849                                 }
 850
 851                         }
 852                 }
 853
 854                 return $endArray;
 855         }
 856
 857 } // end DatabaseSqlite class
 858
 859 /**
 860  * This class allows simple acccess to a SQLite database independently from main database settings
 861  * @ingroup Database
 862  */
 863 class DatabaseSqliteStandalone extends DatabaseSqlite {
 864         public function __construct( $fileName, $flags = 0 ) {
 865                 $this->mFlags = $flags;
 866                 $this->tablePrefix( null );
 867                 $this->openFile( $fileName );
 868         }
 869 }
 870
 871 /**
 872  * @ingroup Database
 873  */
 874 class SQLiteField implements Field {
 875         private $info, $tableName;
 876         function __construct( $info, $tableName ) {
 877                 $this->info = $info;
 878                 $this->tableName = $tableName;
 879         }
 880
 881         function name() {
 882                 return $this->info->name;
 883         }
 884
 885         function tableName() {
 886                 return $this->tableName;
 887         }
 888
 889         function defaultValue() {
 890                 if ( is_string( $this->info->dflt_value ) ) {
 891                         // Typically quoted
 892                         if ( preg_match( '/^\'(.*)\'$', $this->info->dflt_value ) ) {
 893                                 return str_replace( "''", "'", $this->info->dflt_value );
 894                         }
 895                 }
 896                 return $this->info->dflt_value;
 897         }
 898
 899         /**
 900          * @return bool
 901          */
 902         function isNullable() {
 903                 return !$this->info->notnull;
 904         }
 905
 906         function type() {
 907                 return $this->info->type;
 908         }
 909
 910 } // end SQLiteField