includes/db/DatabaseSqlite.php

   1 <?php
   2 /**
   3  * This script is the SQLite database abstraction layer
   4  *
   5  * See maintenance/sqlite/README for development notes and other specific information
   6  * @ingroup Database
   7  * @file
   8  */
   9
  10 /**
  11  * @ingroup Database
  12  */
  13 class DatabaseSqlite extends DatabaseBase {
  14
  15         private static $fulltextEnabled = null;
  16
  17         var $mAffectedRows;
  18         var $mLastResult;
  19         var $mDatabaseFile;
  20         var $mName;
  21
  22         /**
  23          * Constructor.
  24          * Parameters $server, $user and $password are not used.
  25          */
  26         function __construct( $server = false, $user = false, $password = false, $dbName = false, $failFunction = false, $flags = 0 ) {
  27                 $this->mFailFunction = $failFunction;
  28                 $this->mFlags = $flags;
  29                 $this->mName = $dbName;
  30                 $this->open( $server, $user, $password, $dbName );
  31         }
  32
  33         function getType() {
  34                 return 'sqlite';
  35         }
  36
  37         /**
  38          * @todo: check if it should be true like parent class
  39          */
  40         function implicitGroupby()   { return false; }
  41
  42         static function newFromParams( $server, $user, $password, $dbName, $failFunction = false, $flags = 0 ) {
  43                 return new DatabaseSqlite( $server, $user, $password, $dbName, $failFunction, $flags );
  44         }
  45
  46         /** Open an SQLite database and return a resource handle to it
  47          *  NOTE: only $dbName is used, the other parameters are irrelevant for SQLite databases
  48          */
  49         function open( $server, $user, $pass, $dbName ) {
  50                 global $wgSQLiteDataDir;
  51
  52                 $fileName = self::generateFileName( $wgSQLiteDataDir, $dbName );
  53                 if ( !is_readable( $fileName ) ) {
  54                         throw new DBConnectionError( $this, "SQLite database not accessible" );
  55                         $this->mConn = false;
  56                 }
  57                 $this->openFile( $fileName );
  58                 return $this->mConn;
  59         }
  60
  61         /**
  62          * Opens a database file
  63          * @return SQL connection or false if failed
  64          */
  65         function openFile( $fileName ) {
  66                 $this->mDatabaseFile = $fileName;
  67                 try {
  68                         if ( $this->mFlags & DBO_PERSISTENT ) {
  69                                 $this->mConn = new PDO( "sqlite:$fileName", '', '',
  70                                         array( PDO::ATTR_PERSISTENT => true ) );
  71                         } else {
  72                                 $this->mConn = new PDO( "sqlite:$fileName", '', '' );
  73                         }
  74                 } catch ( PDOException $e ) {
  75                         $err = $e->getMessage();
  76                 }
  77                 if ( $this->mConn === false ) {
  78                         wfDebug( "DB connection error: $err\n" );
  79                         if ( !$this->mFailFunction ) {
  80                                 throw new DBConnectionError( $this, $err );
  81                         } else {
  82                                 return false;
  83                         }
  84
  85                 }
  86                 $this->mOpened = !!$this->mConn;
  87                 # set error codes only, don't raise exceptions
  88                 if ( $this->mOpened ) {
  89                         $this->mConn->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_SILENT );
  90                         return true;
  91                 }
  92         }
  93
  94         /**
  95          * Close an SQLite database
  96          */
  97         function close() {
  98                 $this->mOpened = false;
  99                 if ( is_object( $this->mConn ) ) {
 100                         if ( $this->trxLevel() ) $this->commit();
 101                         $this->mConn = null;
 102                 }
 103                 return true;
 104         }
 105
 106         /**
 107          * Generates a database file name. Explicitly public for installer.
 108          * @param $dir String: Directory where database resides
 109          * @param $dbName String: Database name
 110          * @return String
 111          */
 112         public static function generateFileName( $dir, $dbName ) {
 113                 return "$dir/$dbName.sqlite";
 114         }
 115
 116         /**
 117          * Check if the searchindext table is FTS enabled.
 118          * @returns false if not enabled.
 119          */
 120         function checkForEnabledSearch() {
 121                 if ( self::$fulltextEnabled === null ) {
 122                         self::$fulltextEnabled = false;
 123                         $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name = 'searchindex'", __METHOD__ );
 124                         if ( $res ) {
 125                                 $row = $res->fetchRow();
 126                                 self::$fulltextEnabled = stristr($row['sql'], 'fts' ) !== false;
 127                         }
 128                 }
 129                 return self::$fulltextEnabled;
 130         }
 131
 132         /**
 133          * Returns version of currently supported SQLite fulltext search module or false if none present.
 134          * @return String
 135          */
 136         function getFulltextSearchModule() {
 137                 $table = 'dummy_search_test';
 138                 $this->query( "DROP TABLE IF EXISTS $table", __METHOD__ );
 139
 140                 if ( $this->query( "CREATE VIRTUAL TABLE $table USING FTS3(dummy_field)", __METHOD__, true ) ) {
 141                         $this->query( "DROP TABLE IF EXISTS $table", __METHOD__ );
 142                         return 'FTS3';
 143                 }
 144                 return false;
 145         }
 146
 147         /**
 148          * SQLite doesn't allow buffered results or data seeking etc, so we'll use fetchAll as the result
 149          */
 150         function doQuery( $sql ) {
 151                 $res = $this->mConn->query( $sql );
 152                 if ( $res === false ) {
 153                         return false;
 154                 } else {
 155                         $r = $res instanceof ResultWrapper ? $res->result : $res;
 156                         $this->mAffectedRows = $r->rowCount();
 157                         $res = new ResultWrapper( $this, $r->fetchAll() );
 158                 }
 159                 return $res;
 160         }
 161
 162         function freeResult( $res ) {
 163                 if ( $res instanceof ResultWrapper )
 164                         $res->result = null;
 165                 else
 166                         $res = null;
 167         }
 168
 169         function fetchObject( $res ) {
 170                 if ( $res instanceof ResultWrapper )
 171                         $r =& $res->result;
 172                 else
 173                         $r =& $res;
 174
 175                 $cur = current( $r );
 176                 if ( is_array( $cur ) ) {
 177                         next( $r );
 178                         $obj = new stdClass;
 179                         foreach ( $cur as $k => $v )
 180                                 if ( !is_numeric( $k ) )
 181                                         $obj->$k = $v;
 182
 183                         return $obj;
 184                 }
 185                 return false;
 186         }
 187
 188         function fetchRow( $res ) {
 189                 if ( $res instanceof ResultWrapper )
 190                         $r =& $res->result;
 191                 else
 192                         $r =& $res;
 193
 194                 $cur = current( $r );
 195                 if ( is_array( $cur ) ) {
 196                         next( $r );
 197                         return $cur;
 198                 }
 199                 return false;
 200         }
 201
 202         /**
 203          * The PDO::Statement class implements the array interface so count() will work
 204          */
 205         function numRows( $res ) {
 206                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 207                 return count( $r );
 208         }
 209
 210         function numFields( $res ) {
 211                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 212                 return is_array( $r ) ? count( $r[0] ) : 0;
 213         }
 214
 215         function fieldName( $res, $n ) {
 216                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 217                 if ( is_array( $r ) ) {
 218                         $keys = array_keys( $r[0] );
 219                         return $keys[$n];
 220                 }
 221                 return  false;
 222         }
 223
 224         /**
 225          * Use MySQL's naming (accounts for prefix etc) but remove surrounding backticks
 226          */
 227         function tableName( $name ) {
 228                 return str_replace( '`', '', parent::tableName( $name ) );
 229         }
 230
 231         /**
 232          * Index names have DB scope
 233          */
 234         function indexName( $index ) {
 235                 return $index;
 236         }
 237
 238         /**
 239          * This must be called after nextSequenceVal
 240          */
 241         function insertId() {
 242                 return $this->mConn->lastInsertId();
 243         }
 244
 245         function dataSeek( $res, $row ) {
 246                 if ( $res instanceof ResultWrapper )
 247                         $r =& $res->result;
 248                 else
 249                         $r =& $res;
 250                 reset( $r );
 251                 if ( $row > 0 )
 252                         for ( $i = 0; $i < $row; $i++ )
 253                                 next( $r );
 254         }
 255
 256         function lastError() {
 257                 if ( !is_object( $this->mConn ) )
 258                         return "Cannot return last error, no db connection";
 259                 $e = $this->mConn->errorInfo();
 260                 return isset( $e[2] ) ? $e[2] : '';
 261         }
 262
 263         function lastErrno() {
 264                 if ( !is_object( $this->mConn ) ) {
 265                         return "Cannot return last error, no db connection";
 266                 } else {
 267                         $info = $this->mConn->errorInfo();
 268                         return $info[1];
 269                 }
 270         }
 271
 272         function affectedRows() {
 273                 return $this->mAffectedRows;
 274         }
 275
 276         /**
 277          * Returns information about an index
 278          * Returns false if the index does not exist
 279          * - if errors are explicitly ignored, returns NULL on failure
 280          */
 281         function indexInfo( $table, $index, $fname = 'DatabaseSqlite::indexExists' ) {
 282                 $sql = 'PRAGMA index_info(' . $this->addQuotes( $this->indexName( $index ) ) . ')';
 283                 $res = $this->query( $sql, $fname );
 284                 if ( !$res ) {
 285                         return null;
 286                 }
 287                 if ( $res->numRows() == 0 ) {
 288                         return false;
 289                 }
 290                 $info = array();
 291                 foreach ( $res as $row ) {
 292                         $info[] = $row->name;
 293                 }
 294                 return $info;
 295         }
 296
 297         function indexUnique( $table, $index, $fname = 'DatabaseSqlite::indexUnique' ) {
 298                 $row = $this->selectRow( 'sqlite_master', '*',
 299                         array(
 300                                 'type' => 'index',
 301                                 'name' => $this->indexName( $index ),
 302                         ), $fname );
 303                 if ( !$row || !isset( $row->sql ) ) {
 304                         return null;
 305                 }
 306
 307                 // $row->sql will be of the form CREATE [UNIQUE] INDEX ...
 308                 $indexPos = strpos( $row->sql, 'INDEX' );
 309                 if ( $indexPos === false ) {
 310                         return null;
 311                 }
 312                 $firstPart = substr( $row->sql, 0, $indexPos );
 313                 $options = explode( ' ', $firstPart );
 314                 return in_array( 'UNIQUE', $options );
 315         }
 316
 317         /**
 318          * Filter the options used in SELECT statements
 319          */
 320         function makeSelectOptions( $options ) {
 321                 foreach ( $options as $k => $v )
 322                         if ( is_numeric( $k ) && $v == 'FOR UPDATE' )
 323                                 $options[$k] = '';
 324                 return parent::makeSelectOptions( $options );
 325         }
 326
 327         /**
 328          * Based on generic method (parent) with some prior SQLite-sepcific adjustments
 329          */
 330         function insert( $table, $a, $fname = 'DatabaseSqlite::insert', $options = array() ) {
 331                 if ( !count( $a ) ) return true;
 332                 if ( !is_array( $options ) ) $options = array( $options );
 333
 334                 # SQLite uses OR IGNORE not just IGNORE
 335                 foreach ( $options as $k => $v )
 336                         if ( $v == 'IGNORE' )
 337                                 $options[$k] = 'OR IGNORE';
 338
 339                 # SQLite can't handle multi-row inserts, so divide up into multiple single-row inserts
 340                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
 341                         $ret = true;
 342                         foreach ( $a as $k => $v )
 343                                 if ( !parent::insert( $table, $v, "$fname/multi-row", $options ) )
 344                                         $ret = false;
 345                 } else {
 346                         $ret = parent::insert( $table, $a, "$fname/single-row", $options );
 347                 }
 348
 349                 return $ret;
 350         }
 351
 352         function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseSqlite::replace' ) {
 353                 if ( !count( $rows ) ) return true;
 354
 355                 # SQLite can't handle multi-row replaces, so divide up into multiple single-row queries
 356                 if ( isset( $rows[0] ) && is_array( $rows[0] ) ) {
 357                         $ret = true;
 358                         foreach ( $rows as $k => $v )
 359                                 if ( !parent::replace( $table, $uniqueIndexes, $v, "$fname/multi-row" ) )
 360                                         $ret = false;
 361                 } else {
 362                         $ret = parent::replace( $table, $uniqueIndexes, $rows, "$fname/single-row" );
 363                 }
 364
 365                 return $ret;
 366         }
 367
 368         /**
 369          * Returns the size of a text field, or -1 for "unlimited"
 370          * In SQLite this is SQLITE_MAX_LENGTH, by default 1GB. No way to query it though.
 371          */
 372         function textFieldSize( $table, $field ) {
 373                 return - 1;
 374         }
 375
 376         function unionSupportsOrderAndLimit() {
 377                 return false;
 378         }
 379
 380         function unionQueries( $sqls, $all ) {
 381                 $glue = $all ? ' UNION ALL ' : ' UNION ';
 382                 return implode( $glue, $sqls );
 383         }
 384
 385         function wasDeadlock() {
 386                 return $this->lastErrno() == 5; // SQLITE_BUSY
 387         }
 388
 389         function wasErrorReissuable() {
 390                 return $this->lastErrno() ==  17; // SQLITE_SCHEMA;
 391         }
 392
 393         function wasReadOnlyError() {
 394                 return $this->lastErrno() == 8; // SQLITE_READONLY;
 395         }
 396
 397         /**
 398          * @return string wikitext of a link to the server software's web site
 399          */
 400         function getSoftwareLink() {
 401                 return "[http://sqlite.org/ SQLite]";
 402         }
 403
 404         /**
 405          * @return string Version information from the database
 406          */
 407         function getServerVersion() {
 408                 $ver = $this->mConn->getAttribute( PDO::ATTR_SERVER_VERSION );
 409                 return $ver;
 410         }
 411
 412         /**
 413          * Query whether a given column exists in the mediawiki schema
 414          */
 415         function fieldExists( $table, $field, $fname = '' ) {
 416                 $info = $this->fieldInfo( $table, $field );
 417                 return (bool)$info;
 418         }
 419
 420         /**
 421          * Get information about a given field
 422          * Returns false if the field does not exist.
 423          */
 424         function fieldInfo( $table, $field ) {
 425                 $tableName = $this->tableName( $table );
 426                 $sql = 'PRAGMA table_info(' . $this->addQuotes( $tableName ) . ')';
 427                 $res = $this->query( $sql, __METHOD__ );
 428                 foreach ( $res as $row ) {
 429                         if ( $row->name == $field ) {
 430                                 return new SQLiteField( $row, $tableName );
 431                         }
 432                 }
 433                 return false;
 434         }
 435
 436         function begin( $fname = '' ) {
 437                 if ( $this->mTrxLevel == 1 ) $this->commit();
 438                 $this->mConn->beginTransaction();
 439                 $this->mTrxLevel = 1;
 440         }
 441
 442         function commit( $fname = '' ) {
 443                 if ( $this->mTrxLevel == 0 ) return;
 444                 $this->mConn->commit();
 445                 $this->mTrxLevel = 0;
 446         }
 447
 448         function rollback( $fname = '' ) {
 449                 if ( $this->mTrxLevel == 0 ) return;
 450                 $this->mConn->rollBack();
 451                 $this->mTrxLevel = 0;
 452         }
 453
 454         function limitResultForUpdate( $sql, $num ) {
 455                 return $this->limitResult( $sql, $num );
 456         }
 457
 458         function strencode( $s ) {
 459                 return substr( $this->addQuotes( $s ), 1, - 1 );
 460         }
 461
 462         function encodeBlob( $b ) {
 463                 return new Blob( $b );
 464         }
 465
 466         function decodeBlob( $b ) {
 467                 if ( $b instanceof Blob ) {
 468                         $b = $b->fetch();
 469                 }
 470                 return $b;
 471         }
 472
 473         function addQuotes( $s ) {
 474                 if ( $s instanceof Blob ) {
 475                         return "x'" . bin2hex( $s->fetch() ) . "'";
 476                 } else {
 477                         return $this->mConn->quote( $s );
 478                 }
 479         }
 480
 481         function quote_ident( $s ) {
 482                 return $s;
 483         }
 484
 485         function buildLike() {
 486                 $params = func_get_args();
 487                 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
 488                         $params = $params[0];
 489                 }
 490                 return parent::buildLike( $params ) . "ESCAPE '\' ";
 491         }
 492
 493         /**
 494          * How lagged is this slave?
 495          */
 496         public function getLag() {
 497                 return 0;
 498         }
 499
 500         /**
 501          * Called by the installer script (when modified according to the MediaWikiLite installation instructions)
 502          * - this is the same way PostgreSQL works, MySQL reads in tables.sql and interwiki.sql using dbsource (which calls db->sourceFile)
 503          */
 504         public function setup_database() {
 505                 global $IP;
 506
 507                 # Process common MySQL/SQLite table definitions
 508                 $err = $this->sourceFile( "$IP/maintenance/tables.sql" );
 509                 if ( $err !== true ) {
 510                         echo " <b>FAILED</b></li>";
 511                         dieout( htmlspecialchars( $err ) );
 512                 }
 513                 echo " done.</li>";
 514
 515                 # Use DatabasePostgres's code to populate interwiki from MySQL template
 516                 $f = fopen( "$IP/maintenance/interwiki.sql", 'r' );
 517                 if ( !$f ) {
 518                         dieout( "Could not find the interwiki.sql file." );
 519                 }
 520
 521                 $sql = "INSERT INTO interwiki(iw_prefix,iw_url,iw_local) VALUES ";
 522                 while ( !feof( $f ) ) {
 523                         $line = fgets( $f, 1024 );
 524                         $matches = array();
 525                         if ( !preg_match( '/^\s*(\(.+?),(\d)\)/', $line, $matches ) ) continue;
 526                         $this->query( "$sql $matches[1],$matches[2])" );
 527                 }
 528         }
 529
 530         public function getSearchEngine() {
 531                 return "SearchSqlite";
 532         }
 533
 534         /**
 535          * No-op version of deadlockLoop
 536          */
 537         public function deadlockLoop( /*...*/ ) {
 538                 $args = func_get_args();
 539                 $function = array_shift( $args );
 540                 return call_user_func_array( $function, $args );
 541         }
 542
 543         protected function replaceVars( $s ) {
 544                 $s = parent::replaceVars( $s );
 545                 if ( preg_match( '/^\s*(CREATE|ALTER) TABLE/i', $s ) ) {
 546                         // CREATE TABLE hacks to allow schema file sharing with MySQL
 547
 548                         // binary/varbinary column type -> blob
 549                         $s = preg_replace( '/\b(var)?binary(\(\d+\))/i', 'BLOB', $s );
 550                         // no such thing as unsigned
 551                         $s = preg_replace( '/\b(un)?signed\b/i', '', $s );
 552                         // INT -> INTEGER
 553                         $s = preg_replace( '/\b(tiny|small|medium|big|)int(\([\s\d]*\)|\b)/i', 'INTEGER', $s );
 554                         // varchar -> TEXT
 555                         $s = preg_replace( '/\bvarchar\(\d+\)/i', 'TEXT', $s );
 556                         // TEXT normalization
 557                         $s = preg_replace( '/\b(tiny|medium|long)text\b/i', 'TEXT', $s );
 558                         // BLOB normalization
 559                         $s = preg_replace( '/\b(tiny|small|medium|long|)blob\b/i', 'BLOB', $s );
 560                         // BOOL -> INTEGER
 561                         $s = preg_replace( '/\bbool(ean)?\b/i', 'INTEGER', $s );
 562                         // DATETIME -> TEXT
 563                         $s = preg_replace( '/\b(datetime|timestamp)\b/i', 'TEXT', $s );
 564                         // No ENUM type
 565                         $s = preg_replace( '/\benum\s*\([^)]*\)/i', 'TEXT', $s );
 566                         // binary collation type -> nothing
 567                         $s = preg_replace( '/\bbinary\b/i', '', $s );
 568                         // auto_increment -> autoincrement
 569                         $s = preg_replace( '/\bauto_increment\b/i', 'AUTOINCREMENT', $s );
 570                         // No explicit options
 571                         $s = preg_replace( '/\)[^);]*(;?)\s*$/', ')\1', $s );
 572                 } elseif ( preg_match( '/^\s*CREATE (\s*(?:UNIQUE|FULLTEXT)\s+)?INDEX/i', $s ) ) {
 573                         // No truncated indexes
 574                         $s = preg_replace( '/\(\d+\)/', '', $s );
 575                         // No FULLTEXT
 576                         $s = preg_replace( '/\bfulltext\b/i', '', $s );
 577                 }
 578                 return $s;
 579         }
 580
 581         /*
 582          * Build a concatenation list to feed into a SQL query
 583          */
 584         function buildConcat( $stringList ) {
 585                 return '(' . implode( ') || (', $stringList ) . ')';
 586         }
 587
 588         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabaseSqlite::duplicateTableStructure' ) {
 589                 $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name='$oldName' AND type='table'", $fname );
 590                 $obj = $this->fetchObject( $res );
 591                 if ( !$obj ) {
 592                         throw new MWException( "Couldn't retrieve structure for table $oldName" );
 593                 }
 594                 $sql = $obj->sql;
 595                 $sql = preg_replace( '/\b' . preg_quote( $oldName ) . '\b/', $newName, $sql, 1 );
 596                 return $this->query( $sql, $fname );
 597         }
 598
 599 } // end DatabaseSqlite class
 600
 601 /**
 602  * This class allows simple acccess to a SQLite database independently from main database settings
 603  * @ingroup Database
 604  */
 605 class DatabaseSqliteStandalone extends DatabaseSqlite {
 606         public function __construct( $fileName, $flags = 0 ) {
 607                 $this->mFlags = $flags;
 608                 $this->openFile( $fileName );
 609         }
 610 }
 611
 612 /**
 613  * @ingroup Database
 614  */
 615 class SQLiteField {
 616         private $info, $tableName;
 617         function __construct( $info, $tableName ) {
 618                 $this->info = $info;
 619                 $this->tableName = $tableName;
 620         }
 621
 622         function name() {
 623                 return $this->info->name;
 624         }
 625
 626         function tableName() {
 627                 return $this->tableName;
 628         }
 629
 630         function defaultValue() {
 631                 if ( is_string( $this->info->dflt_value ) ) {
 632                         // Typically quoted
 633                         if ( preg_match( '/^\'(.*)\'$', $this->info->dflt_value ) ) {
 634                                 return str_replace( "''", "'", $this->info->dflt_value );
 635                         }
 636                 }
 637                 return $this->info->dflt_value;
 638         }
 639
 640         function maxLength() {
 641                 return -1;
 642         }
 643
 644         function nullable() {
 645                 // SQLite dynamic types are always nullable
 646                 return true;
 647         }
 648
 649         # isKey(),  isMultipleKey() not implemented, MySQL-specific concept.
 650         # Suggest removal from base class [TS]
 651
 652         function type() {
 653                 return $this->info->type;
 654         }
 655
 656 } // end SQLiteField