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