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