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