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