includes/db/DatabasePostgres.php

   1 <?php
   2 /**
   3  * This is the Postgres database abstraction layer.
   4  *
   5  * @file
   6  * @ingroup Database
   7  */
   8
   9 class PostgresField implements Field {
  10         private $name, $tablename, $type, $nullable, $max_length, $deferred, $deferrable, $conname;
  11
  12         /**
  13          * @param $db DatabaseBase
  14          * @param  $table
  15          * @param  $field
  16          * @return null|PostgresField
  17          */
  18         static function fromText( $db, $table, $field ) {
  19                 global $wgDBmwschema;
  20
  21                 $q = <<<SQL
  22 SELECT
  23  attnotnull, attlen, COALESCE(conname, '') AS conname,
  24  COALESCE(condeferred, 'f') AS deferred,
  25  COALESCE(condeferrable, 'f') AS deferrable,
  26  CASE WHEN typname = 'int2' THEN 'smallint'
  27   WHEN typname = 'int4' THEN 'integer'
  28   WHEN typname = 'int8' THEN 'bigint'
  29   WHEN typname = 'bpchar' THEN 'char'
  30  ELSE typname END AS typname
  31 FROM pg_class c
  32 JOIN pg_namespace n ON (n.oid = c.relnamespace)
  33 JOIN pg_attribute a ON (a.attrelid = c.oid)
  34 JOIN pg_type t ON (t.oid = a.atttypid)
  35 LEFT JOIN pg_constraint o ON (o.conrelid = c.oid AND a.attnum = ANY(o.conkey) AND o.contype = 'f')
  36 WHERE relkind = 'r'
  37 AND nspname=%s
  38 AND relname=%s
  39 AND attname=%s;
  40 SQL;
  41
  42                 $table = $db->tableName( $table, false );
  43                 $res = $db->query(
  44                         sprintf( $q,
  45                                 $db->addQuotes( $wgDBmwschema ),
  46                                 $db->addQuotes( $table ),
  47                                 $db->addQuotes( $field )
  48                         )
  49                 );
  50                 $row = $db->fetchObject( $res );
  51                 if ( !$row ) {
  52                         return null;
  53                 }
  54                 $n = new PostgresField;
  55                 $n->type = $row->typname;
  56                 $n->nullable = ( $row->attnotnull == 'f' );
  57                 $n->name = $field;
  58                 $n->tablename = $table;
  59                 $n->max_length = $row->attlen;
  60                 $n->deferrable = ( $row->deferrable == 't' );
  61                 $n->deferred = ( $row->deferred == 't' );
  62                 $n->conname = $row->conname;
  63                 return $n;
  64         }
  65
  66         function name() {
  67                 return $this->name;
  68         }
  69
  70         function tableName() {
  71                 return $this->tablename;
  72         }
  73
  74         function type() {
  75                 return $this->type;
  76         }
  77
  78         function isNullable() {
  79                 return $this->nullable;
  80         }
  81
  82         function maxLength() {
  83                 return $this->max_length;
  84         }
  85
  86         function is_deferrable() {
  87                 return $this->deferrable;
  88         }
  89
  90         function is_deferred() {
  91                 return $this->deferred;
  92         }
  93
  94         function conname() {
  95                 return $this->conname;
  96         }
  97
  98 }
  99
 100 /**
 101  * @ingroup Database
 102  */
 103 class DatabasePostgres extends DatabaseBase {
 104         var $mInsertId = null;
 105         var $mLastResult = null;
 106         var $numeric_version = null;
 107         var $mAffectedRows = null;
 108
 109         function getType() {
 110                 return 'postgres';
 111         }
 112
 113         function cascadingDeletes() {
 114                 return true;
 115         }
 116         function cleanupTriggers() {
 117                 return true;
 118         }
 119         function strictIPs() {
 120                 return true;
 121         }
 122         function realTimestamps() {
 123                 return true;
 124         }
 125         function implicitGroupby() {
 126                 return false;
 127         }
 128         function implicitOrderby() {
 129                 return false;
 130         }
 131         function searchableIPs() {
 132                 return true;
 133         }
 134         function functionalIndexes() {
 135                 return true;
 136         }
 137
 138         function hasConstraint( $name ) {
 139                 global $wgDBmwschema;
 140                 $SQL = "SELECT 1 FROM pg_catalog.pg_constraint c, pg_catalog.pg_namespace n WHERE c.connamespace = n.oid AND conname = '" .
 141                                 pg_escape_string( $this->mConn, $name ) . "' AND n.nspname = '" . pg_escape_string( $this->mConn, $wgDBmwschema ) ."'";
 142                 $res = $this->doQuery( $SQL );
 143                 return $this->numRows( $res );
 144         }
 145
 146         /**
 147          * Usually aborts on failure
 148          */
 149         function open( $server, $user, $password, $dbName ) {
 150                 # Test for Postgres support, to avoid suppressed fatal error
 151                 if ( !function_exists( 'pg_connect' ) ) {
 152                         throw new DBConnectionError( $this, "Postgres functions missing, have you compiled PHP with the --with-pgsql option?\n (Note: if you recently installed PHP, you may need to restart your webserver and database)\n" );
 153                 }
 154
 155                 global $wgDBport;
 156
 157                 if ( !strlen( $user ) ) { # e.g. the class is being loaded
 158                         return;
 159                 }
 160
 161                 $this->close();
 162                 $this->mServer = $server;
 163                 $port = $wgDBport;
 164                 $this->mUser = $user;
 165                 $this->mPassword = $password;
 166                 $this->mDBname = $dbName;
 167
 168                 $connectVars = array(
 169                         'dbname' => $dbName,
 170                         'user' => $user,
 171                         'password' => $password
 172                 );
 173                 if ( $server != false && $server != '' ) {
 174                         $connectVars['host'] = $server;
 175                 }
 176                 if ( $port != false && $port != '' ) {
 177                         $connectVars['port'] = $port;
 178                 }
 179                 $connectString = $this->makeConnectionString( $connectVars, PGSQL_CONNECT_FORCE_NEW );
 180
 181                 $this->installErrorHandler();
 182                 $this->mConn = pg_connect( $connectString );
 183                 $phpError = $this->restoreErrorHandler();
 184
 185                 if ( !$this->mConn ) {
 186                         wfDebug( "DB connection error\n" );
 187                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
 188                         wfDebug( $this->lastError() . "\n" );
 189                         throw new DBConnectionError( $this, $phpError );
 190                 }
 191
 192                 $this->mOpened = true;
 193
 194                 global $wgCommandLineMode;
 195                 # If called from the command-line (e.g. importDump), only show errors
 196                 if ( $wgCommandLineMode ) {
 197                         $this->doQuery( "SET client_min_messages = 'ERROR'" );
 198                 }
 199
 200                 $this->query( "SET client_encoding='UTF8'", __METHOD__ );
 201                 $this->query( "SET datestyle = 'ISO, YMD'", __METHOD__ );
 202                 $this->query( "SET timezone = 'GMT'", __METHOD__ );
 203
 204                 global $wgDBmwschema;
 205                 if ( $this->schemaExists( $wgDBmwschema ) ) {
 206                         $safeschema = $this->addIdentifierQuotes( $wgDBmwschema );
 207                         $this->doQuery( "SET search_path = $safeschema" );
 208                 } else {
 209                         $this->doQuery( "SET search_path = public" );
 210                 }
 211
 212                 return $this->mConn;
 213         }
 214
 215         /**
 216          * Postgres doesn't support selectDB in the same way MySQL does. So if the
 217          * DB name doesn't match the open connection, open a new one
 218          * @return
 219          */
 220         function selectDB( $db ) {
 221                 return (bool)$this->open( $this->mServer, $this->mUser, $this->mPassword, $db );
 222         }
 223
 224         function makeConnectionString( $vars ) {
 225                 $s = '';
 226                 foreach ( $vars as $name => $value ) {
 227                         $s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
 228                 }
 229                 return $s;
 230         }
 231
 232         /**
 233          * Closes a database connection, if it is open
 234          * Returns success, true if already closed
 235          */
 236         function close() {
 237                 $this->mOpened = false;
 238                 if ( $this->mConn ) {
 239                         return pg_close( $this->mConn );
 240                 } else {
 241                         return true;
 242                 }
 243         }
 244
 245         function doQuery( $sql ) {
 246                 if ( function_exists( 'mb_convert_encoding' ) ) {
 247                         $sql = mb_convert_encoding( $sql, 'UTF-8' );
 248                 }
 249                 $this->mLastResult = pg_query( $this->mConn, $sql );
 250                 $this->mAffectedRows = null; // use pg_affected_rows(mLastResult)
 251                 return $this->mLastResult;
 252         }
 253
 254         function queryIgnore( $sql, $fname = 'DatabasePostgres::queryIgnore' ) {
 255                 return $this->query( $sql, $fname, true );
 256         }
 257
 258         function freeResult( $res ) {
 259                 if ( $res instanceof ResultWrapper ) {
 260                         $res = $res->result;
 261                 }
 262                 if ( !@pg_free_result( $res ) ) {
 263                         throw new DBUnexpectedError( $this, "Unable to free Postgres result\n" );
 264                 }
 265         }
 266
 267         function fetchObject( $res ) {
 268                 if ( $res instanceof ResultWrapper ) {
 269                         $res = $res->result;
 270                 }
 271                 @$row = pg_fetch_object( $res );
 272                 # @todo FIXME: HACK HACK HACK HACK debug
 273
 274                 # @todo hashar: not sure if the following test really trigger if the object
 275                 #          fetching failed.
 276                 if( pg_last_error( $this->mConn ) ) {
 277                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 278                 }
 279                 return $row;
 280         }
 281
 282         function fetchRow( $res ) {
 283                 if ( $res instanceof ResultWrapper ) {
 284                         $res = $res->result;
 285                 }
 286                 @$row = pg_fetch_array( $res );
 287                 if( pg_last_error( $this->mConn ) ) {
 288                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 289                 }
 290                 return $row;
 291         }
 292
 293         function numRows( $res ) {
 294                 if ( $res instanceof ResultWrapper ) {
 295                         $res = $res->result;
 296                 }
 297                 @$n = pg_num_rows( $res );
 298                 if( pg_last_error( $this->mConn ) ) {
 299                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 300                 }
 301                 return $n;
 302         }
 303
 304         function numFields( $res ) {
 305                 if ( $res instanceof ResultWrapper ) {
 306                         $res = $res->result;
 307                 }
 308                 return pg_num_fields( $res );
 309         }
 310
 311         function fieldName( $res, $n ) {
 312                 if ( $res instanceof ResultWrapper ) {
 313                         $res = $res->result;
 314                 }
 315                 return pg_field_name( $res, $n );
 316         }
 317
 318         /**
 319          * This must be called after nextSequenceVal
 320          */
 321         function insertId() {
 322                 return $this->mInsertId;
 323         }
 324
 325         function dataSeek( $res, $row ) {
 326                 if ( $res instanceof ResultWrapper ) {
 327                         $res = $res->result;
 328                 }
 329                 return pg_result_seek( $res, $row );
 330         }
 331
 332         function lastError() {
 333                 if ( $this->mConn ) {
 334                         return pg_last_error();
 335                 } else {
 336                         return 'No database connection';
 337                 }
 338         }
 339         function lastErrno() {
 340                 return pg_last_error() ? 1 : 0;
 341         }
 342
 343         function affectedRows() {
 344                 if ( !is_null( $this->mAffectedRows ) ) {
 345                         // Forced result for simulated queries
 346                         return $this->mAffectedRows;
 347                 }
 348                 if( empty( $this->mLastResult ) ) {
 349                         return 0;
 350                 }
 351                 return pg_affected_rows( $this->mLastResult );
 352         }
 353
 354         /**
 355          * Estimate rows in dataset
 356          * Returns estimated count, based on EXPLAIN output
 357          * This is not necessarily an accurate estimate, so use sparingly
 358          * Returns -1 if count cannot be found
 359          * Takes same arguments as Database::select()
 360          */
 361         function estimateRowCount( $table, $vars = '*', $conds='', $fname = 'DatabasePostgres::estimateRowCount', $options = array() ) {
 362                 $options['EXPLAIN'] = true;
 363                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 364                 $rows = -1;
 365                 if ( $res ) {
 366                         $row = $this->fetchRow( $res );
 367                         $count = array();
 368                         if( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
 369                                 $rows = $count[1];
 370                         }
 371                 }
 372                 return $rows;
 373         }
 374
 375         /**
 376          * Returns information about an index
 377          * If errors are explicitly ignored, returns NULL on failure
 378          */
 379         function indexInfo( $table, $index, $fname = 'DatabasePostgres::indexInfo' ) {
 380                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 381                 $res = $this->query( $sql, $fname );
 382                 if ( !$res ) {
 383                         return null;
 384                 }
 385                 foreach ( $res as $row ) {
 386                         if ( $row->indexname == $this->indexName( $index ) ) {
 387                                 return $row;
 388                         }
 389                 }
 390                 return false;
 391         }
 392
 393         function indexUnique( $table, $index, $fname = 'DatabasePostgres::indexUnique' ) {
 394                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 395                         " AND indexdef LIKE 'CREATE UNIQUE%(" .
 396                         $this->strencode( $this->indexName( $index ) ) .
 397                         ")'";
 398                 $res = $this->query( $sql, $fname );
 399                 if ( !$res ) {
 400                         return null;
 401                 }
 402                 foreach ( $res as $row ) {
 403                         return true;
 404                 }
 405                 return false;
 406         }
 407
 408         /**
 409          * INSERT wrapper, inserts an array into a table
 410          *
 411          * $args may be a single associative array, or an array of these with numeric keys,
 412          * for multi-row insert (Postgres version 8.2 and above only).
 413          *
 414          * @param $table   String: Name of the table to insert to.
 415          * @param $args    Array: Items to insert into the table.
 416          * @param $fname   String: Name of the function, for profiling
 417          * @param $options String or Array. Valid options: IGNORE
 418          *
 419          * @return bool Success of insert operation. IGNORE always returns true.
 420          */
 421         function insert( $table, $args, $fname = 'DatabasePostgres::insert', $options = array() ) {
 422                 if ( !count( $args ) ) {
 423                         return true;
 424                 }
 425
 426                 $table = $this->tableName( $table );
 427                 if (! isset( $this->numeric_version ) ) {
 428                         $this->getServerVersion();
 429                 }
 430
 431                 if ( !is_array( $options ) ) {
 432                         $options = array( $options );
 433                 }
 434
 435                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 436                         $multi = true;
 437                         $keys = array_keys( $args[0] );
 438                 } else {
 439                         $multi = false;
 440                         $keys = array_keys( $args );
 441                 }
 442
 443                 // If IGNORE is set, we use savepoints to emulate mysql's behavior
 444                 $ignore = in_array( 'IGNORE', $options ) ? 'mw' : '';
 445
 446                 // If we are not in a transaction, we need to be for savepoint trickery
 447                 $didbegin = 0;
 448                 if ( $ignore ) {
 449                         if ( !$this->mTrxLevel ) {
 450                                 $this->begin();
 451                                 $didbegin = 1;
 452                         }
 453                         $olde = error_reporting( 0 );
 454                         // For future use, we may want to track the number of actual inserts
 455                         // Right now, insert (all writes) simply return true/false
 456                         $numrowsinserted = 0;
 457                 }
 458
 459                 $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 460
 461                 if ( $multi ) {
 462                         if ( $this->numeric_version >= 8.2 && !$ignore ) {
 463                                 $first = true;
 464                                 foreach ( $args as $row ) {
 465                                         if ( $first ) {
 466                                                 $first = false;
 467                                         } else {
 468                                                 $sql .= ',';
 469                                         }
 470                                         $sql .= '(' . $this->makeList( $row ) . ')';
 471                                 }
 472                                 $res = (bool)$this->query( $sql, $fname, $ignore );
 473                         } else {
 474                                 $res = true;
 475                                 $origsql = $sql;
 476                                 foreach ( $args as $row ) {
 477                                         $tempsql = $origsql;
 478                                         $tempsql .= '(' . $this->makeList( $row ) . ')';
 479
 480                                         if ( $ignore ) {
 481                                                 pg_query( $this->mConn, "SAVEPOINT $ignore" );
 482                                         }
 483
 484                                         $tempres = (bool)$this->query( $tempsql, $fname, $ignore );
 485
 486                                         if ( $ignore ) {
 487                                                 $bar = pg_last_error();
 488                                                 if ( $bar != false ) {
 489                                                         pg_query( $this->mConn, "ROLLBACK TO $ignore" );
 490                                                 } else {
 491                                                         pg_query( $this->mConn, "RELEASE $ignore" );
 492                                                         $numrowsinserted++;
 493                                                 }
 494                                         }
 495
 496                                         // If any of them fail, we fail overall for this function call
 497                                         // Note that this will be ignored if IGNORE is set
 498                                         if ( !$tempres ) {
 499                                                 $res = false;
 500                                         }
 501                                 }
 502                         }
 503                 } else {
 504                         // Not multi, just a lone insert
 505                         if ( $ignore ) {
 506                                 pg_query($this->mConn, "SAVEPOINT $ignore");
 507                         }
 508
 509                         $sql .= '(' . $this->makeList( $args ) . ')';
 510                         $res = (bool)$this->query( $sql, $fname, $ignore );
 511                         if ( $ignore ) {
 512                                 $bar = pg_last_error();
 513                                 if ( $bar != false ) {
 514                                         pg_query( $this->mConn, "ROLLBACK TO $ignore" );
 515                                 } else {
 516                                         pg_query( $this->mConn, "RELEASE $ignore" );
 517                                         $numrowsinserted++;
 518                                 }
 519                         }
 520                 }
 521                 if ( $ignore ) {
 522                         $olde = error_reporting( $olde );
 523                         if ( $didbegin ) {
 524                                 $this->commit();
 525                         }
 526
 527                         // Set the affected row count for the whole operation
 528                         $this->mAffectedRows = $numrowsinserted;
 529
 530                         // IGNORE always returns true
 531                         return true;
 532                 }
 533
 534                 return $res;
 535         }
 536
 537         /**
 538          * INSERT SELECT wrapper
 539          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
 540          * Source items may be literals rather then field names, but strings should be quoted with Database::addQuotes()
 541          * $conds may be "*" to copy the whole table
 542          * srcTable may be an array of tables.
 543          * @todo FIXME: Implement this a little better (seperate select/insert)?
 544          */
 545         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'DatabasePostgres::insertSelect',
 546                 $insertOptions = array(), $selectOptions = array() )
 547         {
 548                 $destTable = $this->tableName( $destTable );
 549
 550                 // If IGNORE is set, we use savepoints to emulate mysql's behavior
 551                 $ignore = in_array( 'IGNORE', $insertOptions ) ? 'mw' : '';
 552
 553                 if( is_array( $insertOptions ) ) {
 554                         $insertOptions = implode( ' ', $insertOptions );
 555                 }
 556                 if( !is_array( $selectOptions ) ) {
 557                         $selectOptions = array( $selectOptions );
 558                 }
 559                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
 560                 if( is_array( $srcTable ) ) {
 561                         $srcTable = implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
 562                 } else {
 563                         $srcTable = $this->tableName( $srcTable );
 564                 }
 565
 566                 // If we are not in a transaction, we need to be for savepoint trickery
 567                 $didbegin = 0;
 568                 if ( $ignore ) {
 569                         if( !$this->mTrxLevel ) {
 570                                 $this->begin();
 571                                 $didbegin = 1;
 572                         }
 573                         $olde = error_reporting( 0 );
 574                         $numrowsinserted = 0;
 575                         pg_query( $this->mConn, "SAVEPOINT $ignore");
 576                 }
 577
 578                 $sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
 579                                 " SELECT $startOpts " . implode( ',', $varMap ) .
 580                                 " FROM $srcTable $useIndex";
 581
 582                 if ( $conds != '*' ) {
 583                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
 584                 }
 585
 586                 $sql .= " $tailOpts";
 587
 588                 $res = (bool)$this->query( $sql, $fname, $ignore );
 589                 if( $ignore ) {
 590                         $bar = pg_last_error();
 591                         if( $bar != false ) {
 592                                 pg_query( $this->mConn, "ROLLBACK TO $ignore" );
 593                         } else {
 594                                 pg_query( $this->mConn, "RELEASE $ignore" );
 595                                 $numrowsinserted++;
 596                         }
 597                         $olde = error_reporting( $olde );
 598                         if( $didbegin ) {
 599                                 $this->commit();
 600                         }
 601
 602                         // Set the affected row count for the whole operation
 603                         $this->mAffectedRows = $numrowsinserted;
 604
 605                         // IGNORE always returns true
 606                         return true;
 607                 }
 608
 609                 return $res;
 610         }
 611
 612         function tableName( $name, $quoted = true ) {
 613                 # Replace reserved words with better ones
 614                 switch( $name ) {
 615                         case 'user':
 616                                 return 'mwuser';
 617                         case 'text':
 618                                 return 'pagecontent';
 619                         default:
 620                                 return parent::tableName( $name, $quoted );
 621                 }
 622         }
 623
 624         /**
 625          * Return the next in a sequence, save the value for retrieval via insertId()
 626          */
 627         function nextSequenceValue( $seqName ) {
 628                 $safeseq = str_replace( "'", "''", $seqName );
 629                 $res = $this->query( "SELECT nextval('$safeseq')" );
 630                 $row = $this->fetchRow( $res );
 631                 $this->mInsertId = $row[0];
 632                 return $this->mInsertId;
 633         }
 634
 635         /**
 636          * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
 637          */
 638         function currentSequenceValue( $seqName ) {
 639                 $safeseq = str_replace( "'", "''", $seqName );
 640                 $res = $this->query( "SELECT currval('$safeseq')" );
 641                 $row = $this->fetchRow( $res );
 642                 $currval = $row[0];
 643                 return $currval;
 644         }
 645
 646         /**
 647          * REPLACE query wrapper
 648          * Postgres simulates this with a DELETE followed by INSERT
 649          * $row is the row to insert, an associative array
 650          * $uniqueIndexes is an array of indexes. Each element may be either a
 651          * field name or an array of field names
 652          *
 653          * It may be more efficient to leave off unique indexes which are unlikely to collide.
 654          * However if you do this, you run the risk of encountering errors which wouldn't have
 655          * occurred in MySQL
 656          */
 657         function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabasePostgres::replace' ) {
 658                 $table = $this->tableName( $table );
 659
 660                 if ( count( $rows ) == 0 ) {
 661                         return;
 662                 }
 663
 664                 # Single row case
 665                 if ( !is_array( reset( $rows ) ) ) {
 666                         $rows = array( $rows );
 667                 }
 668
 669                 foreach( $rows as $row ) {
 670                         # Delete rows which collide
 671                         if ( $uniqueIndexes ) {
 672                                 $sql = "DELETE FROM $table WHERE ";
 673                                 $first = true;
 674                                 foreach ( $uniqueIndexes as $index ) {
 675                                         if ( $first ) {
 676                                                 $first = false;
 677                                                 $sql .= '(';
 678                                         } else {
 679                                                 $sql .= ') OR (';
 680                                         }
 681                                         if ( is_array( $index ) ) {
 682                                                 $first2 = true;
 683                                                 foreach ( $index as $col ) {
 684                                                         if ( $first2 ) {
 685                                                                 $first2 = false;
 686                                                         } else {
 687                                                                 $sql .= ' AND ';
 688                                                         }
 689                                                         $sql .= $col.'=' . $this->addQuotes( $row[$col] );
 690                                                 }
 691                                         } else {
 692                                                 $sql .= $index.'=' . $this->addQuotes( $row[$index] );
 693                                         }
 694                                 }
 695                                 $sql .= ')';
 696                                 $this->query( $sql, $fname );
 697                         }
 698
 699                         # Now insert the row
 700                         $sql = "INSERT INTO $table (" . $this->makeList( array_keys( $row ), LIST_NAMES ) .') VALUES (' .
 701                                 $this->makeList( $row, LIST_COMMA ) . ')';
 702                         $this->query( $sql, $fname );
 703                 }
 704         }
 705
 706         # DELETE where the condition is a join
 707         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'DatabasePostgres::deleteJoin' ) {
 708                 if ( !$conds ) {
 709                         throw new DBUnexpectedError( $this, 'DatabasePostgres::deleteJoin() called with empty $conds' );
 710                 }
 711
 712                 $delTable = $this->tableName( $delTable );
 713                 $joinTable = $this->tableName( $joinTable );
 714                 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
 715                 if ( $conds != '*' ) {
 716                         $sql .= 'WHERE ' . $this->makeList( $conds, LIST_AND );
 717                 }
 718                 $sql .= ')';
 719
 720                 $this->query( $sql, $fname );
 721         }
 722
 723         # Returns the size of a text field, or -1 for "unlimited"
 724         function textFieldSize( $table, $field ) {
 725                 $table = $this->tableName( $table );
 726                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
 727                         FROM pg_class c, pg_attribute a, pg_type t
 728                         WHERE relname='$table' AND a.attrelid=c.oid AND
 729                                 a.atttypid=t.oid and a.attname='$field'";
 730                 $res =$this->query( $sql );
 731                 $row = $this->fetchObject( $res );
 732                 if ( $row->ftype == 'varchar' ) {
 733                         $size = $row->size - 4;
 734                 } else {
 735                         $size = $row->size;
 736                 }
 737                 return $size;
 738         }
 739
 740         function limitResult( $sql, $limit, $offset = false ) {
 741                 return "$sql LIMIT $limit " . ( is_numeric( $offset ) ? " OFFSET {$offset} " : '' );
 742         }
 743
 744         function wasDeadlock() {
 745                 return $this->lastErrno() == '40P01';
 746         }
 747
 748         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabasePostgres::duplicateTableStructure' ) {
 749                 $newName = $this->addIdentifierQuotes( $newName );
 750                 $oldName = $this->addIdentifierQuotes( $oldName );
 751                 return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName (LIKE $oldName INCLUDING DEFAULTS)", $fname );
 752         }
 753
 754         function timestamp( $ts = 0 ) {
 755                 return wfTimestamp( TS_POSTGRES, $ts );
 756         }
 757
 758         /**
 759          * Return aggregated value function call
 760          */
 761         function aggregateValue( $valuedata, $valuename = 'value' ) {
 762                 return $valuedata;
 763         }
 764
 765         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 766                 // Ignore errors during error handling to avoid infinite recursion
 767                 $ignore = $this->ignoreErrors( true );
 768                 $this->mErrorCount++;
 769
 770                 if ( $ignore || $tempIgnore ) {
 771                         wfDebug( "SQL ERROR (ignored): $error\n" );
 772                         $this->ignoreErrors( $ignore );
 773                 } else {
 774                         $message = "A database error has occurred.  Did you forget to run maintenance/update.php after upgrading?  See: http://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script\n" .
 775                                 "Query: $sql\n" .
 776                                 "Function: $fname\n" .
 777                                 "Error: $errno $error\n";
 778                         throw new DBUnexpectedError( $this, $message );
 779                 }
 780         }
 781
 782         /**
 783          * @return string wikitext of a link to the server software's web site
 784          */
 785         public static function getSoftwareLink() {
 786                 return '[http://www.postgresql.org/ PostgreSQL]';
 787         }
 788
 789         /**
 790          * @return string Version information from the database
 791          */
 792         function getServerVersion() {
 793                 if ( !isset( $this->numeric_version ) ) {
 794                         $versionInfo = pg_version( $this->mConn );
 795                         if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
 796                                 // Old client, abort install
 797                                 $this->numeric_version = '7.3 or earlier';
 798                         } elseif ( isset( $versionInfo['server'] ) ) {
 799                                 // Normal client
 800                                 $this->numeric_version = $versionInfo['server'];
 801                         } else {
 802                                 // Bug 16937: broken pgsql extension from PHP<5.3
 803                                 $this->numeric_version = pg_parameter_status( $this->mConn, 'server_version' );
 804                         }
 805                 }
 806                 return $this->numeric_version;
 807         }
 808
 809         /**
 810          * Query whether a given relation exists (in the given schema, or the
 811          * default mw one if not given)
 812          */
 813         function relationExists( $table, $types, $schema = false ) {
 814                 global $wgDBmwschema;
 815                 if ( !is_array( $types ) ) {
 816                         $types = array( $types );
 817                 }
 818                 if ( !$schema ) {
 819                         $schema = $wgDBmwschema;
 820                 }
 821                 $table = $this->tableName( $table, false );
 822                 $etable = $this->addQuotes( $table );
 823                 $eschema = $this->addQuotes( $schema );
 824                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
 825                         . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
 826                         . "AND c.relkind IN ('" . implode( "','", $types ) . "')";
 827                 $res = $this->query( $SQL );
 828                 $count = $res ? $res->numRows() : 0;
 829                 return (bool)$count;
 830         }
 831
 832         /**
 833          * For backward compatibility, this function checks both tables and
 834          * views.
 835          */
 836         function tableExists( $table, $schema = false ) {
 837                 return $this->relationExists( $table, array( 'r', 'v' ), $schema );
 838         }
 839
 840         function sequenceExists( $sequence, $schema = false ) {
 841                 return $this->relationExists( $sequence, 'S', $schema );
 842         }
 843
 844         function triggerExists( $table, $trigger ) {
 845                 global $wgDBmwschema;
 846
 847                 $q = <<<SQL
 848         SELECT 1 FROM pg_class, pg_namespace, pg_trigger
 849                 WHERE relnamespace=pg_namespace.oid AND relkind='r'
 850                       AND tgrelid=pg_class.oid
 851                       AND nspname=%s AND relname=%s AND tgname=%s
 852 SQL;
 853                 $res = $this->query(
 854                         sprintf(
 855                                 $q,
 856                                 $this->addQuotes( $wgDBmwschema ),
 857                                 $this->addQuotes( $table ),
 858                                 $this->addQuotes( $trigger )
 859                         )
 860                 );
 861                 if ( !$res ) {
 862                         return null;
 863                 }
 864                 $rows = $res->numRows();
 865                 return $rows;
 866         }
 867
 868         function ruleExists( $table, $rule ) {
 869                 global $wgDBmwschema;
 870                 $exists = $this->selectField( 'pg_rules', 'rulename',
 871                         array(
 872                                 'rulename' => $rule,
 873                                 'tablename' => $table,
 874                                 'schemaname' => $wgDBmwschema
 875                         )
 876                 );
 877                 return $exists === $rule;
 878         }
 879
 880         function constraintExists( $table, $constraint ) {
 881                 global $wgDBmwschema;
 882                 $SQL = sprintf( "SELECT 1 FROM information_schema.table_constraints ".
 883                            "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
 884                         $this->addQuotes( $wgDBmwschema ),
 885                         $this->addQuotes( $table ),
 886                         $this->addQuotes( $constraint )
 887                 );
 888                 $res = $this->query( $SQL );
 889                 if ( !$res ) {
 890                         return null;
 891                 }
 892                 $rows = $res->numRows();
 893                 return $rows;
 894         }
 895
 896         /**
 897          * Query whether a given schema exists. Returns the name of the owner
 898          */
 899         function schemaExists( $schema ) {
 900                 $eschema = str_replace( "'", "''", $schema );
 901                 $SQL = "SELECT rolname FROM pg_catalog.pg_namespace n, pg_catalog.pg_roles r "
 902                                 ."WHERE n.nspowner=r.oid AND n.nspname = '$eschema'";
 903                 $res = $this->query( $SQL );
 904                 if ( $res && $res->numRows() ) {
 905                         $row = $res->fetchObject();
 906                         $owner = $row->rolname;
 907                 } else {
 908                         $owner = false;
 909                 }
 910                 return $owner;
 911         }
 912
 913         function fieldInfo( $table, $field ) {
 914                 return PostgresField::fromText( $this, $table, $field );
 915         }
 916
 917         /**
 918          * pg_field_type() wrapper
 919          */
 920         function fieldType( $res, $index ) {
 921                 if ( $res instanceof ResultWrapper ) {
 922                         $res = $res->result;
 923                 }
 924                 return pg_field_type( $res, $index );
 925         }
 926
 927         /* Not even sure why this is used in the main codebase... */
 928         function limitResultForUpdate( $sql, $num ) {
 929                 return $sql;
 930         }
 931
 932         function encodeBlob( $b ) {
 933                 return new Blob( pg_escape_bytea( $this->mConn, $b ) );
 934         }
 935
 936         function decodeBlob( $b ) {
 937                 if ( $b instanceof Blob ) {
 938                         $b = $b->fetch();
 939                 }
 940                 return pg_unescape_bytea( $b );
 941         }
 942
 943         function strencode( $s ) { # Should not be called by us
 944                 return pg_escape_string( $this->mConn, $s );
 945         }
 946
 947         function addQuotes( $s ) {
 948                 if ( is_null( $s ) ) {
 949                         return 'NULL';
 950                 } elseif ( is_bool( $s ) ) {
 951                         return intval( $s );
 952                 } elseif ( $s instanceof Blob ) {
 953                         return "'" . $s->fetch( $s ) . "'";
 954                 }
 955                 return "'" . pg_escape_string( $this->mConn, $s ) . "'";
 956         }
 957
 958         /**
 959          * Postgres specific version of replaceVars.
 960          * Calls the parent version in Database.php
 961          *
 962          * @private
 963          *
 964          * @param $ins String: SQL string, read from a stream (usually tables.sql)
 965          *
 966          * @return string SQL string
 967          */
 968         protected function replaceVars( $ins ) {
 969                 $ins = parent::replaceVars( $ins );
 970
 971                 if ( $this->numeric_version >= 8.3 ) {
 972                         // Thanks for not providing backwards-compatibility, 8.3
 973                         $ins = preg_replace( "/to_tsvector\s*\(\s*'default'\s*,/", 'to_tsvector(', $ins );
 974                 }
 975
 976                 if ( $this->numeric_version <= 8.1 ) { // Our minimum version
 977                         $ins = str_replace( 'USING gin', 'USING gist', $ins );
 978                 }
 979
 980                 return $ins;
 981         }
 982
 983         /**
 984          * Various select options
 985          *
 986          * @private
 987          *
 988          * @param $options Array: an associative array of options to be turned into
 989          *              an SQL query, valid keys are listed in the function.
 990          * @return array
 991          */
 992         function makeSelectOptions( $options ) {
 993                 $preLimitTail = $postLimitTail = '';
 994                 $startOpts = $useIndex = '';
 995
 996                 $noKeyOptions = array();
 997                 foreach ( $options as $key => $option ) {
 998                         if ( is_numeric( $key ) ) {
 999                                 $noKeyOptions[$option] = true;
1000                         }
1001                 }
1002
1003                 if ( isset( $options['GROUP BY'] ) ) {
1004                         $gb = is_array( $options['GROUP BY'] )
1005                                 ? implode( ',', $options['GROUP BY'] )
1006                                 : $options['GROUP BY'];
1007                         $preLimitTail .= " GROUP BY {$gb}";
1008                 }
1009
1010                 if ( isset( $options['HAVING'] ) ) {
1011                         $preLimitTail .= " HAVING {$options['HAVING']}";
1012                 }
1013
1014                 if ( isset( $options['ORDER BY'] ) ) {
1015                         $ob = is_array( $options['ORDER BY'] )
1016                                 ? implode( ',', $options['ORDER BY'] )
1017                                 : $options['ORDER BY'];
1018                         $preLimitTail .= " ORDER BY {$ob}";
1019                 }
1020
1021                 //if ( isset( $options['LIMIT'] ) ) {
1022                 //      $tailOpts .= $this->limitResult( '', $options['LIMIT'],
1023                 //              isset( $options['OFFSET'] ) ? $options['OFFSET']
1024                 //              : false );
1025                 //}
1026
1027                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1028                         $postLimitTail .= ' FOR UPDATE';
1029                 }
1030                 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1031                         $postLimitTail .= ' LOCK IN SHARE MODE';
1032                 }
1033                 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1034                         $startOpts .= 'DISTINCT';
1035                 }
1036
1037                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1038         }
1039
1040         function setFakeMaster( $enabled = true ) {}
1041
1042         function getDBname() {
1043                 return $this->mDBname;
1044         }
1045
1046         function getServer() {
1047                 return $this->mServer;
1048         }
1049
1050         function buildConcat( $stringList ) {
1051                 return implode( ' || ', $stringList );
1052         }
1053
1054         public function getSearchEngine() {
1055                 return 'SearchPostgres';
1056         }
1057 } // end DatabasePostgres class