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