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