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 Database {
  14
  15         var $mAffectedRows;
  16         var $mLastResult;
  17         var $mDatabaseFile;
  18
  19         /**
  20          * Constructor
  21          */
  22         function __construct($server = false, $user = false, $password = false, $dbName = false, $failFunction = false, $flags = 0) {
  23                 global $wgOut,$wgSQLiteDataDir, $wgSQLiteDataDirMode;
  24                 if ("$wgSQLiteDataDir" == '') $wgSQLiteDataDir = dirname($_SERVER['DOCUMENT_ROOT']).'/data';
  25                 if (!is_dir($wgSQLiteDataDir)) wfMkdirParents( $wgSQLiteDataDir, $wgSQLiteDataDirMode );
  26                 $this->mFailFunction = $failFunction;
  27                 $this->mFlags = $flags;
  28                 $this->mDatabaseFile = "$wgSQLiteDataDir/$dbName.sqlite";
  29                 $this->open($server, $user, $password, $dbName);
  30         }
  31
  32         /**
  33          * todo: check if these should be true like parent class
  34          */
  35         function implicitGroupby()   { return false; }
  36         function implicitOrderby()   { return false; }
  37
  38         static function newFromParams($server, $user, $password, $dbName, $failFunction = false, $flags = 0) {
  39                 return new DatabaseSqlite($server, $user, $password, $dbName, $failFunction, $flags);
  40         }
  41
  42         /** Open an SQLite database and return a resource handle to it
  43          *  NOTE: only $dbName is used, the other parameters are irrelevant for SQLite databases
  44          */
  45         function open($server,$user,$pass,$dbName) {
  46                 $this->mConn = false;
  47                 if ($dbName) {
  48                         $file = $this->mDatabaseFile;
  49                         try {
  50                                 if ( $this->mFlags & DBO_PERSISTENT ) {
  51                                         $this->mConn = new PDO( "sqlite:$file", $user, $pass,
  52                                                 array( PDO::ATTR_PERSISTENT => true ) );
  53                                 } else {
  54                                         $this->mConn = new PDO( "sqlite:$file", $user, $pass );
  55                                 }
  56                         } catch ( PDOException $e ) {
  57                                 $err = $e->getMessage();
  58                         }
  59                         if ( $this->mConn === false ) {
  60                                 wfDebug( "DB connection error: $err\n" );
  61                                 if ( !$this->mFailFunction ) {
  62                                         throw new DBConnectionError( $this, $err );
  63                                 } else {
  64                                         return false;
  65                                 }
  66
  67                         }
  68                         $this->mOpened = $this->mConn;
  69                         # set error codes only, don't raise exceptions
  70                         $this->mConn->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_SILENT );
  71                 }
  72                 return $this->mConn;
  73         }
  74
  75         /**
  76          * Close an SQLite database
  77          */
  78         function close() {
  79                 $this->mOpened = false;
  80                 if (is_object($this->mConn)) {
  81                         if ($this->trxLevel()) $this->immediateCommit();
  82                         $this->mConn = null;
  83                 }
  84                 return true;
  85         }
  86
  87         /**
  88          * SQLite doesn't allow buffered results or data seeking etc, so we'll use fetchAll as the result
  89          */
  90         function doQuery($sql) {
  91                 $res = $this->mConn->query($sql);
  92                 if ($res === false) $this->reportQueryError($this->lastError(),$this->lastErrno(),$sql,__FUNCTION__);
  93                 else {
  94                         $r = $res instanceof ResultWrapper ? $res->result : $res;
  95                         $this->mAffectedRows = $r->rowCount();
  96                         $res = new ResultWrapper($this,$r->fetchAll());
  97                 }
  98                 return $res;
  99         }
 100
 101         function freeResult(&$res) {
 102                 if ($res instanceof ResultWrapper) $res->result = NULL; else $res = NULL;
 103         }
 104
 105         function fetchObject(&$res) {
 106                 if ($res instanceof ResultWrapper) $r =& $res->result; else $r =& $res;
 107                 $cur = current($r);
 108                 if (is_array($cur)) {
 109                         next($r);
 110                         $obj = new stdClass;
 111                         foreach ($cur as $k => $v) if (!is_numeric($k)) $obj->$k = $v;
 112                         return $obj;
 113                 }
 114                 return false;
 115         }
 116
 117         function fetchRow(&$res) {
 118                 if ($res instanceof ResultWrapper) $r =& $res->result; else $r =& $res;
 119                 $cur = current($r);
 120                 if (is_array($cur)) {
 121                         next($r);
 122                         return $cur;
 123                 }
 124                 return false;
 125         }
 126
 127         /**
 128          * The PDO::Statement class implements the array interface so count() will work
 129          */
 130         function numRows(&$res) {
 131                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 132                 return count($r);
 133         }
 134
 135         function numFields(&$res) {
 136                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 137                 return is_array($r) ? count($r[0]) : 0;
 138         }
 139
 140         function fieldName(&$res,$n) {
 141                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 142                 if (is_array($r)) {
 143                         $keys = array_keys($r[0]);
 144                         return $keys[$n];
 145                 }
 146                 return  false;
 147         }
 148
 149         /**
 150          * Use MySQL's naming (accounts for prefix etc) but remove surrounding backticks
 151          */
 152         function tableName($name) {
 153                 return str_replace('`','',parent::tableName($name));
 154         }
 155
 156         /**
 157          * This must be called after nextSequenceVal
 158          */
 159         function insertId() {
 160                 return $this->mConn->lastInsertId();
 161         }
 162
 163         function dataSeek(&$res,$row) {
 164                 if ($res instanceof ResultWrapper) $r =& $res->result; else $r =& $res;
 165                 reset($r);
 166                 if ($row > 0) for ($i = 0; $i < $row; $i++) next($r);
 167         }
 168
 169         function lastError() {
 170                 if (!is_object($this->mConn)) return "Cannot return last error, no db connection";
 171                 $e = $this->mConn->errorInfo();
 172                 return isset($e[2]) ? $e[2] : '';
 173         }
 174
 175         function lastErrno() {
 176                 if (!is_object($this->mConn)) return "Cannot return last error, no db connection";
 177                 return $this->mConn->errorCode();
 178         }
 179
 180         function affectedRows() {
 181                 return $this->mAffectedRows;
 182         }
 183
 184         /**
 185          * Returns information about an index
 186          * - if errors are explicitly ignored, returns NULL on failure
 187          */
 188         function indexInfo($table, $index, $fname = 'Database::indexExists') {
 189                 return false;
 190         }
 191
 192         function indexUnique($table, $index, $fname = 'Database::indexUnique') {
 193                 return false;
 194         }
 195
 196         /**
 197          * Filter the options used in SELECT statements
 198          */
 199         function makeSelectOptions($options) {
 200                 foreach ($options as $k => $v) if (is_numeric($k) && $v == 'FOR UPDATE') $options[$k] = '';
 201                 return parent::makeSelectOptions($options);
 202         }
 203
 204         /**
 205          * Based on MySQL method (parent) with some prior SQLite-sepcific adjustments
 206          */
 207         function insert($table, $a, $fname = 'DatabaseSqlite::insert', $options = array()) {
 208                 if (!count($a)) return true;
 209                 if (!is_array($options)) $options = array($options);
 210
 211                 # SQLite uses OR IGNORE not just IGNORE
 212                 foreach ($options as $k => $v) if ($v == 'IGNORE') $options[$k] = 'OR IGNORE';
 213
 214                 # SQLite can't handle multi-row inserts, so divide up into multiple single-row inserts
 215                 if (isset($a[0]) && is_array($a[0])) {
 216                         $ret = true;
 217                         foreach ($a as $k => $v) if (!parent::insert($table,$v,"$fname/multi-row",$options)) $ret = false;
 218                 }
 219                 else $ret = parent::insert($table,$a,"$fname/single-row",$options);
 220
 221                 return $ret;
 222         }
 223
 224         /**
 225          * SQLite does not have a "USE INDEX" clause, so return an empty string
 226          */
 227         function useIndexClause($index) {
 228                 return '';
 229         }
 230
 231         # Returns the size of a text field, or -1 for "unlimited"
 232         function textFieldSize($table, $field) {
 233                 return -1;
 234         }
 235
 236         /**
 237          * No low priority option in SQLite
 238          */
 239         function lowPriorityOption() {
 240                 return '';
 241         }
 242
 243         /**
 244          * Returns an SQL expression for a simple conditional.
 245          * - uses CASE on SQLite
 246          */
 247         function conditional($cond, $trueVal, $falseVal) {
 248                 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
 249         }
 250
 251         function wasDeadlock() {
 252                 return $this->lastErrno() == SQLITE_BUSY;
 253         }
 254
 255         /**
 256          * @return string wikitext of a link to the server software's web site
 257          */
 258         function getSoftwareLink() {
 259                 return "[http://sqlite.org/ SQLite]";
 260         }
 261
 262         /**
 263          * @return string Version information from the database
 264          */
 265         function getServerVersion() {
 266                 global $wgContLang;
 267                 $ver = $this->mConn->getAttribute(PDO::ATTR_SERVER_VERSION);
 268                 $size = $wgContLang->formatSize(filesize($this->mDatabaseFile));
 269                 $file = basename($this->mDatabaseFile);
 270                 return $ver." ($file: $size)";
 271         }
 272
 273         /**
 274          * Query whether a given column exists in the mediawiki schema
 275          */
 276         function fieldExists($table, $field) { return true; }
 277
 278         function fieldInfo($table, $field) { return SQLiteField::fromText($this, $table, $field); }
 279
 280         function begin() {
 281                 if ($this->mTrxLevel == 1) $this->commit();
 282                 $this->mConn->beginTransaction();
 283                 $this->mTrxLevel = 1;
 284         }
 285
 286         function commit() {
 287                 if ($this->mTrxLevel == 0) return;
 288                 $this->mConn->commit();
 289                 $this->mTrxLevel = 0;
 290         }
 291
 292         function rollback() {
 293                 if ($this->mTrxLevel == 0) return;
 294                 $this->mConn->rollBack();
 295                 $this->mTrxLevel = 0;
 296         }
 297
 298         function limitResultForUpdate($sql, $num) {
 299                 return $sql;
 300         }
 301
 302         function strencode($s) {
 303                 return substr($this->addQuotes($s),1,-1);
 304         }
 305
 306         function encodeBlob($b) {
 307                 return new Blob( $b );
 308         }
 309
 310         function decodeBlob($b) {
 311                 if ($b instanceof Blob) {
 312                         $b = $b->fetch();
 313                 }
 314                 return $b;
 315         }
 316
 317         function addQuotes($s) {
 318                 if ( $s instanceof Blob ) {
 319                         return "x'" . bin2hex( $s->fetch() ) . "'";
 320                 } else {
 321                         return $this->mConn->quote($s);
 322                 }
 323         }
 324
 325         function quote_ident($s) { return $s; }
 326
 327         /**
 328          * For now, does nothing
 329          */
 330         function selectDB($db) { return true; }
 331
 332         /**
 333          * not done
 334          */
 335         public function setTimeout($timeout) { return; }
 336
 337         function ping() {
 338                 wfDebug("Function ping() not written for SQLite yet");
 339                 return true;
 340         }
 341
 342         /**
 343          * How lagged is this slave?
 344          */
 345         public function getLag() {
 346                 return 0;
 347         }
 348
 349         /**
 350          * Called by the installer script (when modified according to the MediaWikiLite installation instructions)
 351          * - this is the same way PostgreSQL works, MySQL reads in tables.sql and interwiki.sql using dbsource (which calls db->sourceFile)
 352          */
 353         public function setup_database() {
 354                 global $IP,$wgSQLiteDataDir,$wgDBTableOptions;
 355                 $wgDBTableOptions = '';
 356                 $mysql_tmpl  = "$IP/maintenance/tables.sql";
 357                 $mysql_iw    = "$IP/maintenance/interwiki.sql";
 358                 $sqlite_tmpl = "$IP/maintenance/sqlite/tables.sql";
 359
 360                 # Make an SQLite template file if it doesn't exist (based on the same one MySQL uses to create a new wiki db)
 361                 if (!file_exists($sqlite_tmpl)) {
 362                         $sql = file_get_contents($mysql_tmpl);
 363                         $sql = preg_replace('/^\s*--.*?$/m','',$sql); # strip comments
 364                         $sql = preg_replace('/^\s*(UNIQUE)?\s*(PRIMARY)?\s*KEY.+?$/m','',$sql);
 365                         $sql = preg_replace('/^\s*(UNIQUE )?INDEX.+?$/m','',$sql); # These indexes should be created with a CREATE INDEX query
 366                         $sql = preg_replace('/^\s*FULLTEXT.+?$/m','',$sql);        # Full text indexes
 367                         $sql = preg_replace('/ENUM\(.+?\)/','TEXT',$sql); # Make ENUM's into TEXT's
 368                         $sql = preg_replace('/binary\(\d+\)/','BLOB',$sql);
 369                         $sql = preg_replace('/(TYPE|MAX_ROWS|AVG_ROW_LENGTH)=\w+/','',$sql);
 370                         $sql = preg_replace('/,\s*\)/s',')',$sql); # removing previous items may leave a trailing comma
 371                         $sql = str_replace('binary','',$sql);
 372                         $sql = str_replace('auto_increment','PRIMARY KEY AUTOINCREMENT',$sql);
 373                         $sql = str_replace(' unsigned','',$sql);
 374                         $sql = str_replace(' int ',' INTEGER ',$sql);
 375                         $sql = str_replace('NOT NULL','',$sql);
 376
 377                         # Tidy up and write file
 378                         $sql = preg_replace('/^\s*^/m','',$sql); # Remove empty lines
 379                         $sql = preg_replace('/;$/m',";\n",$sql); # Separate each statement with an empty line
 380                         file_put_contents($sqlite_tmpl,$sql);
 381                 }
 382
 383                 # Parse the SQLite template replacing inline variables such as /*$wgDBprefix*/
 384                 $err = $this->sourceFile($sqlite_tmpl);
 385                 if ($err !== true) $this->reportQueryError($err,0,$sql,__FUNCTION__);
 386
 387                 # Use DatabasePostgres's code to populate interwiki from MySQL template
 388                 $f = fopen($mysql_iw,'r');
 389                 if ($f == false) dieout("<li>Could not find the interwiki.sql file");
 390                 $sql = "INSERT INTO interwiki(iw_prefix,iw_url,iw_local) VALUES ";
 391                 while (!feof($f)) {
 392                         $line = fgets($f,1024);
 393                         $matches = array();
 394                         if (!preg_match('/^\s*(\(.+?),(\d)\)/', $line, $matches)) continue;
 395                         $this->query("$sql $matches[1],$matches[2])");
 396                 }
 397         }
 398
 399         /**
 400          * No-op lock functions
 401          */
 402         public function lock( $lockName, $method ) {
 403                 return true;
 404         }
 405         public function unlock( $lockName, $method ) {
 406                 return true;
 407         }
 408
 409         public function getSearchEngine() {
 410                 return "SearchEngineDummy";
 411         }
 412
 413 }
 414
 415 /**
 416  * @ingroup Database
 417  */
 418 class SQLiteField extends MySQLField {
 419
 420         function __construct() {
 421         }
 422
 423         static function fromText($db, $table, $field) {
 424                 $n = new SQLiteField;
 425                 $n->name = $field;
 426                 $n->tablename = $table;
 427                 return $n;
 428         }
 429
 430 } // end DatabaseSqlite class
 431