includes/db/DatabasePostgres.php

   1 <?php
   2 /**
   3  * This is the Postgres database abstraction layer.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Database
  22  */
  23
  24 class PostgresField implements Field {
  25         private $name, $tablename, $type, $nullable, $max_length, $deferred, $deferrable, $conname,
  26                 $has_default, $default;
  27
  28         /**
  29          * @param $db DatabaseBase
  30          * @param  $table
  31          * @param  $field
  32          * @return null|PostgresField
  33          */
  34         static function fromText( $db, $table, $field ) {
  35                 $q = <<<SQL
  36 SELECT
  37  attnotnull, attlen, conname AS conname,
  38  atthasdef,
  39  adsrc,
  40  COALESCE(condeferred, 'f') AS deferred,
  41  COALESCE(condeferrable, 'f') AS deferrable,
  42  CASE WHEN typname = 'int2' THEN 'smallint'
  43   WHEN typname = 'int4' THEN 'integer'
  44   WHEN typname = 'int8' THEN 'bigint'
  45   WHEN typname = 'bpchar' THEN 'char'
  46  ELSE typname END AS typname
  47 FROM pg_class c
  48 JOIN pg_namespace n ON (n.oid = c.relnamespace)
  49 JOIN pg_attribute a ON (a.attrelid = c.oid)
  50 JOIN pg_type t ON (t.oid = a.atttypid)
  51 LEFT JOIN pg_constraint o ON (o.conrelid = c.oid AND a.attnum = ANY(o.conkey) AND o.contype = 'f')
  52 LEFT JOIN pg_attrdef d on c.oid=d.adrelid and a.attnum=d.adnum
  53 WHERE relkind = 'r'
  54 AND nspname=%s
  55 AND relname=%s
  56 AND attname=%s;
  57 SQL;
  58
  59                 $table = $db->tableName( $table, 'raw' );
  60                 $res = $db->query(
  61                         sprintf( $q,
  62                                 $db->addQuotes( $db->getCoreSchema() ),
  63                                 $db->addQuotes( $table ),
  64                                 $db->addQuotes( $field )
  65                         )
  66                 );
  67                 $row = $db->fetchObject( $res );
  68                 if ( !$row ) {
  69                         return null;
  70                 }
  71                 $n = new PostgresField;
  72                 $n->type = $row->typname;
  73                 $n->nullable = ( $row->attnotnull == 'f' );
  74                 $n->name = $field;
  75                 $n->tablename = $table;
  76                 $n->max_length = $row->attlen;
  77                 $n->deferrable = ( $row->deferrable == 't' );
  78                 $n->deferred = ( $row->deferred == 't' );
  79                 $n->conname = $row->conname;
  80                 $n->has_default = ( $row->atthasdef === 't' );
  81                 $n->default = $row->adsrc;
  82                 return $n;
  83         }
  84
  85         function name() {
  86                 return $this->name;
  87         }
  88
  89         function tableName() {
  90                 return $this->tablename;
  91         }
  92
  93         function type() {
  94                 return $this->type;
  95         }
  96
  97         function isNullable() {
  98                 return $this->nullable;
  99         }
 100
 101         function maxLength() {
 102                 return $this->max_length;
 103         }
 104
 105         function is_deferrable() {
 106                 return $this->deferrable;
 107         }
 108
 109         function is_deferred() {
 110                 return $this->deferred;
 111         }
 112
 113         function conname() {
 114                 return $this->conname;
 115         }
 116         /**
 117          * @since 1.19
 118          */
 119         function defaultValue() {
 120                 if( $this->has_default ) {
 121                         return $this->default;
 122                 } else {
 123                         return false;
 124                 }
 125         }
 126
 127 }
 128
 129 /**
 130  * Used to debug transaction processing
 131  * Only used if $wgDebugDBTransactions is true
 132  *
 133  * @since 1.19
 134  * @ingroup Database
 135  */
 136 class PostgresTransactionState {
 137
 138         static $WATCHED = array(
 139                 array(
 140                         "desc" => "%s: Connection state changed from %s -> %s\n",
 141                         "states" => array(
 142                                 PGSQL_CONNECTION_OK       => "OK",
 143                                 PGSQL_CONNECTION_BAD      => "BAD"
 144                         )
 145                 ),
 146                 array(
 147                         "desc" => "%s: Transaction state changed from %s -> %s\n",
 148                         "states" => array(
 149                                 PGSQL_TRANSACTION_IDLE    => "IDLE",
 150                                 PGSQL_TRANSACTION_ACTIVE  => "ACTIVE",
 151                                 PGSQL_TRANSACTION_INTRANS => "TRANS",
 152                                 PGSQL_TRANSACTION_INERROR => "ERROR",
 153                                 PGSQL_TRANSACTION_UNKNOWN => "UNKNOWN"
 154                         )
 155                 )
 156         );
 157
 158         public function __construct( $conn ) {
 159                 $this->mConn = $conn;
 160                 $this->update();
 161                 $this->mCurrentState = $this->mNewState;
 162         }
 163
 164         public function update() {
 165                 $this->mNewState = array(
 166                         pg_connection_status( $this->mConn ),
 167                         pg_transaction_status( $this->mConn )
 168                 );
 169         }
 170
 171         public function check() {
 172                 global $wgDebugDBTransactions;
 173                 $this->update();
 174                 if ( $wgDebugDBTransactions ) {
 175                         if ( $this->mCurrentState !== $this->mNewState ) {
 176                                 $old = reset( $this->mCurrentState );
 177                                 $new = reset( $this->mNewState );
 178                                 foreach ( self::$WATCHED as $watched ) {
 179                                         if ($old !== $new) {
 180                                                 $this->log_changed($old, $new, $watched);
 181                                         }
 182                                         $old = next( $this->mCurrentState );
 183                                         $new = next( $this->mNewState );
 184
 185                                 }
 186                         }
 187                 }
 188                 $this->mCurrentState = $this->mNewState;
 189         }
 190
 191         protected function describe_changed( $status, $desc_table ) {
 192                 if( isset( $desc_table[$status] ) ) {
 193                         return $desc_table[$status];
 194                 } else {
 195                         return "STATUS " . $status;
 196                 }
 197         }
 198
 199         protected function log_changed( $old, $new, $watched ) {
 200                 wfDebug(sprintf($watched["desc"],
 201                         $this->mConn,
 202                         $this->describe_changed( $old, $watched["states"] ),
 203                         $this->describe_changed( $new, $watched["states"] ))
 204                 );
 205         }
 206 }
 207
 208 /**
 209  * Manage savepoints within a transaction
 210  * @ingroup Database
 211  * @since 1.19
 212  */
 213 class SavepointPostgres {
 214         /**
 215          * Establish a savepoint within a transaction
 216          */
 217         protected $dbw;
 218         protected $id;
 219         protected $didbegin;
 220
 221         public function __construct ($dbw, $id) {
 222                 $this->dbw = $dbw;
 223                 $this->id = $id;
 224                 $this->didbegin = false;
 225                 /* If we are not in a transaction, we need to be for savepoint trickery */
 226                 if ( !$dbw->trxLevel() ) {
 227                                 $dbw->begin( "FOR SAVEPOINT" );
 228                                 $this->didbegin = true;
 229                 }
 230         }
 231
 232         public function __destruct() {
 233                 if ( $this->didbegin ) {
 234                         $this->dbw->rollback();
 235                 }
 236         }
 237
 238         public function commit() {
 239                 if ( $this->didbegin ) {
 240                         $this->dbw->commit();
 241                 }
 242         }
 243
 244         protected function query( $keyword, $msg_ok, $msg_failed ) {
 245                 global $wgDebugDBTransactions;
 246                 if ( $this->dbw->doQuery( $keyword . " " . $this->id ) !== false ) {
 247                         if ( $wgDebugDBTransactions ) {
 248                                 wfDebug( sprintf ($msg_ok, $this->id ) );
 249                         }
 250                 } else {
 251                         wfDebug( sprintf ($msg_failed, $this->id ) );
 252                 }
 253         }
 254
 255         public function savepoint() {
 256                 $this->query("SAVEPOINT",
 257                         "Transaction state: savepoint \"%s\" established.\n",
 258                         "Transaction state: establishment of savepoint \"%s\" FAILED.\n"
 259                 );
 260         }
 261
 262         public function release() {
 263                 $this->query("RELEASE",
 264                         "Transaction state: savepoint \"%s\" released.\n",
 265                         "Transaction state: release of savepoint \"%s\" FAILED.\n"
 266                 );
 267         }
 268
 269         public function rollback() {
 270                 $this->query("ROLLBACK TO",
 271                         "Transaction state: savepoint \"%s\" rolled back.\n",
 272                         "Transaction state: rollback of savepoint \"%s\" FAILED.\n"
 273                 );
 274         }
 275
 276         public function __toString() {
 277                 return (string)$this->id;
 278         }
 279 }
 280
 281 /**
 282  * @ingroup Database
 283  */
 284 class DatabasePostgres extends DatabaseBase {
 285         var $mInsertId = null;
 286         var $mLastResult = null;
 287         var $numeric_version = null;
 288         var $mAffectedRows = null;
 289
 290         function getType() {
 291                 return 'postgres';
 292         }
 293
 294         function cascadingDeletes() {
 295                 return true;
 296         }
 297         function cleanupTriggers() {
 298                 return true;
 299         }
 300         function strictIPs() {
 301                 return true;
 302         }
 303         function realTimestamps() {
 304                 return true;
 305         }
 306         function implicitGroupby() {
 307                 return false;
 308         }
 309         function implicitOrderby() {
 310                 return false;
 311         }
 312         function searchableIPs() {
 313                 return true;
 314         }
 315         function functionalIndexes() {
 316                 return true;
 317         }
 318
 319         function hasConstraint( $name ) {
 320                 $SQL = "SELECT 1 FROM pg_catalog.pg_constraint c, pg_catalog.pg_namespace n WHERE c.connamespace = n.oid AND conname = '" .
 321                                 pg_escape_string( $this->mConn, $name ) . "' AND n.nspname = '" . pg_escape_string( $this->mConn, $this->getCoreSchema() ) ."'";
 322                 $res = $this->doQuery( $SQL );
 323                 return $this->numRows( $res );
 324         }
 325
 326         /**
 327          * Usually aborts on failure
 328          * @return DatabaseBase|null
 329          */
 330         function open( $server, $user, $password, $dbName ) {
 331                 # Test for Postgres support, to avoid suppressed fatal error
 332                 if ( !function_exists( 'pg_connect' ) ) {
 333                         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" );
 334                 }
 335
 336                 global $wgDBport;
 337
 338                 if ( !strlen( $user ) ) { # e.g. the class is being loaded
 339                         return;
 340                 }
 341
 342                 $this->mServer = $server;
 343                 $port = $wgDBport;
 344                 $this->mUser = $user;
 345                 $this->mPassword = $password;
 346                 $this->mDBname = $dbName;
 347
 348                 $connectVars = array(
 349                         'dbname' => $dbName,
 350                         'user' => $user,
 351                         'password' => $password
 352                 );
 353                 if ( $server != false && $server != '' ) {
 354                         $connectVars['host'] = $server;
 355                 }
 356                 if ( $port != false && $port != '' ) {
 357                         $connectVars['port'] = $port;
 358                 }
 359                 if ( $this->mFlags & DBO_SSL ) {
 360                         $connectVars['sslmode'] = 1;
 361                 }
 362
 363                 $this->connectString = $this->makeConnectionString( $connectVars, PGSQL_CONNECT_FORCE_NEW );
 364                 $this->close();
 365                 $this->installErrorHandler();
 366                 $this->mConn = pg_connect( $this->connectString );
 367                 $phpError = $this->restoreErrorHandler();
 368
 369                 if ( !$this->mConn ) {
 370                         wfDebug( "DB connection error\n" );
 371                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
 372                         wfDebug( $this->lastError() . "\n" );
 373                         throw new DBConnectionError( $this, str_replace( "\n", ' ', $phpError ) );
 374                 }
 375
 376                 $this->mOpened = true;
 377                 $this->mTransactionState = new PostgresTransactionState( $this->mConn );
 378
 379                 global $wgCommandLineMode;
 380                 # If called from the command-line (e.g. importDump), only show errors
 381                 if ( $wgCommandLineMode ) {
 382                         $this->doQuery( "SET client_min_messages = 'ERROR'" );
 383                 }
 384
 385                 $this->query( "SET client_encoding='UTF8'", __METHOD__ );
 386                 $this->query( "SET datestyle = 'ISO, YMD'", __METHOD__ );
 387                 $this->query( "SET timezone = 'GMT'", __METHOD__ );
 388                 $this->query( "SET standard_conforming_strings = on", __METHOD__ );
 389
 390                 global $wgDBmwschema;
 391                 $this->determineCoreSchema( $wgDBmwschema );
 392
 393                 return $this->mConn;
 394         }
 395
 396         /**
 397          * Postgres doesn't support selectDB in the same way MySQL does. So if the
 398          * DB name doesn't match the open connection, open a new one
 399          * @return
 400          */
 401         function selectDB( $db ) {
 402                 if ( $this->mDBname !== $db ) {
 403                         return (bool)$this->open( $this->mServer, $this->mUser, $this->mPassword, $db );
 404                 } else {
 405                         return true;
 406                 }
 407         }
 408
 409         function makeConnectionString( $vars ) {
 410                 $s = '';
 411                 foreach ( $vars as $name => $value ) {
 412                         $s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
 413                 }
 414                 return $s;
 415         }
 416
 417         /**
 418          * Closes a database connection, if it is open
 419          * Returns success, true if already closed
 420          * @return bool
 421          */
 422         protected function closeConnection() {
 423                 return pg_close( $this->mConn );
 424         }
 425
 426         public function doQuery( $sql ) {
 427                 if ( function_exists( 'mb_convert_encoding' ) ) {
 428                         $sql = mb_convert_encoding( $sql, 'UTF-8' );
 429                 }
 430                 $this->mTransactionState->check();
 431                 if( pg_send_query( $this->mConn, $sql ) === false ) {
 432                         throw new DBUnexpectedError( $this, "Unable to post new query to PostgreSQL\n" );
 433                 }
 434                 $this->mLastResult = pg_get_result( $this->mConn );
 435                 $this->mTransactionState->check();
 436                 $this->mAffectedRows = null;
 437                 if ( pg_result_error( $this->mLastResult ) ) {
 438                         return false;
 439                 }
 440                 return $this->mLastResult;
 441         }
 442
 443         protected function dumpError () {
 444                 $diags = array( PGSQL_DIAG_SEVERITY,
 445                                 PGSQL_DIAG_SQLSTATE,
 446                                 PGSQL_DIAG_MESSAGE_PRIMARY,
 447                                 PGSQL_DIAG_MESSAGE_DETAIL,
 448                                 PGSQL_DIAG_MESSAGE_HINT,
 449                                 PGSQL_DIAG_STATEMENT_POSITION,
 450                                 PGSQL_DIAG_INTERNAL_POSITION,
 451                                 PGSQL_DIAG_INTERNAL_QUERY,
 452                                 PGSQL_DIAG_CONTEXT,
 453                                 PGSQL_DIAG_SOURCE_FILE,
 454                                 PGSQL_DIAG_SOURCE_LINE,
 455                                 PGSQL_DIAG_SOURCE_FUNCTION );
 456                 foreach ( $diags as $d ) {
 457                         wfDebug( sprintf("PgSQL ERROR(%d): %s\n", $d, pg_result_error_field( $this->mLastResult, $d ) ) );
 458                 }
 459         }
 460
 461         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 462                 /* Transaction stays in the ERROR state until rolledback */
 463                 if ( $tempIgnore ) {
 464                         /* Check for constraint violation */
 465                         if ( $errno === '23505' ) {
 466                                 parent::reportQueryError( $error, $errno, $sql, $fname, $tempIgnore );
 467                                 return;
 468                         }
 469                 }
 470                 /* Don't ignore serious errors */
 471                 $this->rollback( __METHOD__ );
 472                 parent::reportQueryError( $error, $errno, $sql, $fname, false );
 473         }
 474
 475
 476         function queryIgnore( $sql, $fname = 'DatabasePostgres::queryIgnore' ) {
 477                 return $this->query( $sql, $fname, true );
 478         }
 479
 480         function freeResult( $res ) {
 481                 if ( $res instanceof ResultWrapper ) {
 482                         $res = $res->result;
 483                 }
 484                 wfSuppressWarnings();
 485                 $ok = pg_free_result( $res );
 486                 wfRestoreWarnings();
 487                 if ( !$ok ) {
 488                         throw new DBUnexpectedError( $this, "Unable to free Postgres result\n" );
 489                 }
 490         }
 491
 492         function fetchObject( $res ) {
 493                 if ( $res instanceof ResultWrapper ) {
 494                         $res = $res->result;
 495                 }
 496                 wfSuppressWarnings();
 497                 $row = pg_fetch_object( $res );
 498                 wfRestoreWarnings();
 499                 # @todo FIXME: HACK HACK HACK HACK debug
 500
 501                 # @todo hashar: not sure if the following test really trigger if the object
 502                 #          fetching failed.
 503                 if( pg_last_error( $this->mConn ) ) {
 504                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 505                 }
 506                 return $row;
 507         }
 508
 509         function fetchRow( $res ) {
 510                 if ( $res instanceof ResultWrapper ) {
 511                         $res = $res->result;
 512                 }
 513                 wfSuppressWarnings();
 514                 $row = pg_fetch_array( $res );
 515                 wfRestoreWarnings();
 516                 if( pg_last_error( $this->mConn ) ) {
 517                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 518                 }
 519                 return $row;
 520         }
 521
 522         function numRows( $res ) {
 523                 if ( $res instanceof ResultWrapper ) {
 524                         $res = $res->result;
 525                 }
 526                 wfSuppressWarnings();
 527                 $n = pg_num_rows( $res );
 528                 wfRestoreWarnings();
 529                 if( pg_last_error( $this->mConn ) ) {
 530                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 531                 }
 532                 return $n;
 533         }
 534
 535         function numFields( $res ) {
 536                 if ( $res instanceof ResultWrapper ) {
 537                         $res = $res->result;
 538                 }
 539                 return pg_num_fields( $res );
 540         }
 541
 542         function fieldName( $res, $n ) {
 543                 if ( $res instanceof ResultWrapper ) {
 544                         $res = $res->result;
 545                 }
 546                 return pg_field_name( $res, $n );
 547         }
 548
 549         /**
 550          * This must be called after nextSequenceVal
 551          * @return null
 552          */
 553         function insertId() {
 554                 return $this->mInsertId;
 555         }
 556
 557         function dataSeek( $res, $row ) {
 558                 if ( $res instanceof ResultWrapper ) {
 559                         $res = $res->result;
 560                 }
 561                 return pg_result_seek( $res, $row );
 562         }
 563
 564         function lastError() {
 565                 if ( $this->mConn ) {
 566                         if ( $this->mLastResult ) {
 567                                 return pg_result_error( $this->mLastResult );
 568                         } else {
 569                                 return pg_last_error();
 570                         }
 571                 } else {
 572                         return 'No database connection';
 573                 }
 574         }
 575         function lastErrno() {
 576                 if ( $this->mLastResult ) {
 577                         return pg_result_error_field( $this->mLastResult, PGSQL_DIAG_SQLSTATE );
 578                 } else {
 579                         return false;
 580                 }
 581         }
 582
 583         function affectedRows() {
 584                 if ( !is_null( $this->mAffectedRows ) ) {
 585                         // Forced result for simulated queries
 586                         return $this->mAffectedRows;
 587                 }
 588                 if( empty( $this->mLastResult ) ) {
 589                         return 0;
 590                 }
 591                 return pg_affected_rows( $this->mLastResult );
 592         }
 593
 594         /**
 595          * Estimate rows in dataset
 596          * Returns estimated count, based on EXPLAIN output
 597          * This is not necessarily an accurate estimate, so use sparingly
 598          * Returns -1 if count cannot be found
 599          * Takes same arguments as Database::select()
 600          * @return int
 601          */
 602         function estimateRowCount( $table, $vars = '*', $conds='', $fname = 'DatabasePostgres::estimateRowCount', $options = array() ) {
 603                 $options['EXPLAIN'] = true;
 604                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 605                 $rows = -1;
 606                 if ( $res ) {
 607                         $row = $this->fetchRow( $res );
 608                         $count = array();
 609                         if( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
 610                                 $rows = $count[1];
 611                         }
 612                 }
 613                 return $rows;
 614         }
 615
 616         /**
 617          * Returns information about an index
 618          * If errors are explicitly ignored, returns NULL on failure
 619          * @return bool|null
 620          */
 621         function indexInfo( $table, $index, $fname = 'DatabasePostgres::indexInfo' ) {
 622                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 623                 $res = $this->query( $sql, $fname );
 624                 if ( !$res ) {
 625                         return null;
 626                 }
 627                 foreach ( $res as $row ) {
 628                         if ( $row->indexname == $this->indexName( $index ) ) {
 629                                 return $row;
 630                         }
 631                 }
 632                 return false;
 633         }
 634
 635         /**
 636          * Returns is of attributes used in index
 637          *
 638          * @since 1.19
 639          * @return Array
 640          */
 641         function indexAttributes ( $index, $schema = false ) {
 642                 if ( $schema === false )
 643                         $schema = $this->getCoreSchema();
 644                 /*
 645                  * A subquery would be not needed if we didn't care about the order
 646                  * of attributes, but we do
 647                  */
 648                 $sql = <<<__INDEXATTR__
 649
 650                         SELECT opcname,
 651                                 attname,
 652                                 i.indoption[s.g] as option,
 653                                 pg_am.amname
 654                         FROM
 655                                 (SELECT generate_series(array_lower(isub.indkey,1), array_upper(isub.indkey,1)) AS g
 656                                         FROM
 657                                                 pg_index isub
 658                                         JOIN pg_class cis
 659                                                 ON cis.oid=isub.indexrelid
 660                                         JOIN pg_namespace ns
 661                                                 ON cis.relnamespace = ns.oid
 662                                         WHERE cis.relname='$index' AND ns.nspname='$schema') AS s,
 663                                 pg_attribute,
 664                                 pg_opclass opcls,
 665                                 pg_am,
 666                                 pg_class ci
 667                                 JOIN pg_index i
 668                                         ON ci.oid=i.indexrelid
 669                                 JOIN pg_class ct
 670                                         ON ct.oid = i.indrelid
 671                                 JOIN pg_namespace n
 672                                         ON ci.relnamespace = n.oid
 673                                 WHERE
 674                                         ci.relname='$index' AND n.nspname='$schema'
 675                                         AND     attrelid = ct.oid
 676                                         AND     i.indkey[s.g] = attnum
 677                                         AND     i.indclass[s.g] = opcls.oid
 678                                         AND     pg_am.oid = opcls.opcmethod
 679 __INDEXATTR__;
 680                 $res = $this->query($sql, __METHOD__);
 681                 $a = array();
 682                 if ( $res ) {
 683                         foreach ( $res as $row ) {
 684                                 $a[] = array(
 685                                         $row->attname,
 686                                         $row->opcname,
 687                                         $row->amname,
 688                                         $row->option);
 689                         }
 690                 } else {
 691                         return null;
 692                 }
 693                 return $a;
 694         }
 695
 696
 697         function indexUnique( $table, $index, $fname = 'DatabasePostgres::indexUnique' ) {
 698                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 699                         " AND indexdef LIKE 'CREATE UNIQUE%(" .
 700                         $this->strencode( $this->indexName( $index ) ) .
 701                         ")'";
 702                 $res = $this->query( $sql, $fname );
 703                 if ( !$res ) {
 704                         return null;
 705                 }
 706                 foreach ( $res as $row ) {
 707                         return true;
 708                 }
 709                 return false;
 710         }
 711
 712         /**
 713          * INSERT wrapper, inserts an array into a table
 714          *
 715          * $args may be a single associative array, or an array of these with numeric keys,
 716          * for multi-row insert (Postgres version 8.2 and above only).
 717          *
 718          * @param $table   String: Name of the table to insert to.
 719          * @param $args    Array: Items to insert into the table.
 720          * @param $fname   String: Name of the function, for profiling
 721          * @param $options String or Array. Valid options: IGNORE
 722          *
 723          * @return bool Success of insert operation. IGNORE always returns true.
 724          */
 725         function insert( $table, $args, $fname = 'DatabasePostgres::insert', $options = array() ) {
 726                 if ( !count( $args ) ) {
 727                         return true;
 728                 }
 729
 730                 $table = $this->tableName( $table );
 731                 if (! isset( $this->numeric_version ) ) {
 732                         $this->getServerVersion();
 733                 }
 734
 735                 if ( !is_array( $options ) ) {
 736                         $options = array( $options );
 737                 }
 738
 739                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 740                         $multi = true;
 741                         $keys = array_keys( $args[0] );
 742                 } else {
 743                         $multi = false;
 744                         $keys = array_keys( $args );
 745                 }
 746
 747                 // If IGNORE is set, we use savepoints to emulate mysql's behavior
 748                 $savepoint = null;
 749                 if ( in_array( 'IGNORE', $options ) ) {
 750                         $savepoint = new SavepointPostgres( $this, 'mw' );
 751                         $olde = error_reporting( 0 );
 752                         // For future use, we may want to track the number of actual inserts
 753                         // Right now, insert (all writes) simply return true/false
 754                         $numrowsinserted = 0;
 755                 }
 756
 757                 $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 758
 759                 if ( $multi ) {
 760                         if ( $this->numeric_version >= 8.2 && !$savepoint ) {
 761                                 $first = true;
 762                                 foreach ( $args as $row ) {
 763                                         if ( $first ) {
 764                                                 $first = false;
 765                                         } else {
 766                                                 $sql .= ',';
 767                                         }
 768                                         $sql .= '(' . $this->makeList( $row ) . ')';
 769                                 }
 770                                 $res = (bool)$this->query( $sql, $fname, $savepoint );
 771                         } else {
 772                                 $res = true;
 773                                 $origsql = $sql;
 774                                 foreach ( $args as $row ) {
 775                                         $tempsql = $origsql;
 776                                         $tempsql .= '(' . $this->makeList( $row ) . ')';
 777
 778                                         if ( $savepoint ) {
 779                                                 $savepoint->savepoint();
 780                                         }
 781
 782                                         $tempres = (bool)$this->query( $tempsql, $fname, $savepoint );
 783
 784                                         if ( $savepoint ) {
 785                                                 $bar = pg_last_error();
 786                                                 if ( $bar != false ) {
 787                                                         $savepoint->rollback();
 788                                                 } else {
 789                                                         $savepoint->release();
 790                                                         $numrowsinserted++;
 791                                                 }
 792                                         }
 793
 794                                         // If any of them fail, we fail overall for this function call
 795                                         // Note that this will be ignored if IGNORE is set
 796                                         if ( !$tempres ) {
 797                                                 $res = false;
 798                                         }
 799                                 }
 800                         }
 801                 } else {
 802                         // Not multi, just a lone insert
 803                         if ( $savepoint ) {
 804                                 $savepoint->savepoint();
 805                         }
 806
 807                         $sql .= '(' . $this->makeList( $args ) . ')';
 808                         $res = (bool)$this->query( $sql, $fname, $savepoint );
 809                         if ( $savepoint ) {
 810                                 $bar = pg_last_error();
 811                                 if ( $bar != false ) {
 812                                         $savepoint->rollback();
 813                                 } else {
 814                                         $savepoint->release();
 815                                         $numrowsinserted++;
 816                                 }
 817                         }
 818                 }
 819                 if ( $savepoint ) {
 820                         $olde = error_reporting( $olde );
 821                         $savepoint->commit();
 822
 823                         // Set the affected row count for the whole operation
 824                         $this->mAffectedRows = $numrowsinserted;
 825
 826                         // IGNORE always returns true
 827                         return true;
 828                 }
 829
 830                 return $res;
 831         }
 832
 833         /**
 834          * INSERT SELECT wrapper
 835          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
 836          * Source items may be literals rather then field names, but strings should be quoted with Database::addQuotes()
 837          * $conds may be "*" to copy the whole table
 838          * srcTable may be an array of tables.
 839          * @todo FIXME: Implement this a little better (seperate select/insert)?
 840          * @return bool
 841          */
 842         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'DatabasePostgres::insertSelect',
 843                 $insertOptions = array(), $selectOptions = array() )
 844         {
 845                 $destTable = $this->tableName( $destTable );
 846
 847                 if( !is_array( $insertOptions ) ) {
 848                         $insertOptions = array( $insertOptions );
 849                 }
 850
 851                 /*
 852                  * If IGNORE is set, we use savepoints to emulate mysql's behavior
 853                  * Ignore LOW PRIORITY option, since it is MySQL-specific
 854                  */
 855                 $savepoint = null;
 856                 if ( in_array( 'IGNORE', $insertOptions ) ) {
 857                         $savepoint = new SavepointPostgres( $this, 'mw' );
 858                         $olde = error_reporting( 0 );
 859                         $numrowsinserted = 0;
 860                         $savepoint->savepoint();
 861                 }
 862
 863                 if( !is_array( $selectOptions ) ) {
 864                         $selectOptions = array( $selectOptions );
 865                 }
 866                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
 867                 if( is_array( $srcTable ) ) {
 868                         $srcTable = implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
 869                 } else {
 870                         $srcTable = $this->tableName( $srcTable );
 871                 }
 872
 873                 $sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
 874                                 " SELECT $startOpts " . implode( ',', $varMap ) .
 875                                 " FROM $srcTable $useIndex";
 876
 877                 if ( $conds != '*' ) {
 878                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
 879                 }
 880
 881                 $sql .= " $tailOpts";
 882
 883                 $res = (bool)$this->query( $sql, $fname, $savepoint );
 884                 if( $savepoint ) {
 885                         $bar = pg_last_error();
 886                         if( $bar != false ) {
 887                                 $savepoint->rollback();
 888                         } else {
 889                                 $savepoint->release();
 890                                 $numrowsinserted++;
 891                         }
 892                         $olde = error_reporting( $olde );
 893                         $savepoint->commit();
 894
 895                         // Set the affected row count for the whole operation
 896                         $this->mAffectedRows = $numrowsinserted;
 897
 898                         // IGNORE always returns true
 899                         return true;
 900                 }
 901
 902                 return $res;
 903         }
 904
 905         function tableName( $name, $format = 'quoted' ) {
 906                 # Replace reserved words with better ones
 907                 switch( $name ) {
 908                         case 'user':
 909                                 return $this->realTableName( 'mwuser', $format );
 910                         case 'text':
 911                                 return $this->realTableName( 'pagecontent', $format );
 912                         default:
 913                                 return $this->realTableName( $name, $format );
 914                 }
 915         }
 916
 917         /* Don't cheat on installer */
 918         function realTableName( $name, $format = 'quoted' ) {
 919                 return parent::tableName( $name, $format );
 920         }
 921
 922         /**
 923          * Return the next in a sequence, save the value for retrieval via insertId()
 924          * @return null
 925          */
 926         function nextSequenceValue( $seqName ) {
 927                 $safeseq = str_replace( "'", "''", $seqName );
 928                 $res = $this->query( "SELECT nextval('$safeseq')" );
 929                 $row = $this->fetchRow( $res );
 930                 $this->mInsertId = $row[0];
 931                 return $this->mInsertId;
 932         }
 933
 934         /**
 935          * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
 936          * @return
 937          */
 938         function currentSequenceValue( $seqName ) {
 939                 $safeseq = str_replace( "'", "''", $seqName );
 940                 $res = $this->query( "SELECT currval('$safeseq')" );
 941                 $row = $this->fetchRow( $res );
 942                 $currval = $row[0];
 943                 return $currval;
 944         }
 945
 946         # Returns the size of a text field, or -1 for "unlimited"
 947         function textFieldSize( $table, $field ) {
 948                 $table = $this->tableName( $table );
 949                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
 950                         FROM pg_class c, pg_attribute a, pg_type t
 951                         WHERE relname='$table' AND a.attrelid=c.oid AND
 952                                 a.atttypid=t.oid and a.attname='$field'";
 953                 $res =$this->query( $sql );
 954                 $row = $this->fetchObject( $res );
 955                 if ( $row->ftype == 'varchar' ) {
 956                         $size = $row->size - 4;
 957                 } else {
 958                         $size = $row->size;
 959                 }
 960                 return $size;
 961         }
 962
 963         function limitResult( $sql, $limit, $offset = false ) {
 964                 return "$sql LIMIT $limit " . ( is_numeric( $offset ) ? " OFFSET {$offset} " : '' );
 965         }
 966
 967         function wasDeadlock() {
 968                 return $this->lastErrno() == '40P01';
 969         }
 970
 971         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabasePostgres::duplicateTableStructure' ) {
 972                 $newName = $this->addIdentifierQuotes( $newName );
 973                 $oldName = $this->addIdentifierQuotes( $oldName );
 974                 return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName (LIKE $oldName INCLUDING DEFAULTS)", $fname );
 975         }
 976
 977         function listTables( $prefix = null, $fname = 'DatabasePostgres::listTables' ) {
 978                 $eschema = $this->addQuotes( $this->getCoreSchema() );
 979                 $result = $this->query( "SELECT tablename FROM pg_tables WHERE schemaname = $eschema", $fname );
 980                 $endArray = array();
 981
 982                 foreach( $result as $table ) {
 983                         $vars = get_object_vars($table);
 984                         $table = array_pop( $vars );
 985                         if( !$prefix || strpos( $table, $prefix ) === 0 ) {
 986                                 $endArray[] = $table;
 987                         }
 988                 }
 989
 990                 return $endArray;
 991         }
 992
 993         function timestamp( $ts = 0 ) {
 994                 return wfTimestamp( TS_POSTGRES, $ts );
 995         }
 996
 997         /*
 998          * Posted by cc[plus]php[at]c2se[dot]com on 25-Mar-2009 09:12
 999          * to http://www.php.net/manual/en/ref.pgsql.php
1000          *
1001          * Parsing a postgres array can be a tricky problem, he's my
1002          * take on this, it handles multi-dimensional arrays plus
1003          * escaping using a nasty regexp to determine the limits of each
1004          * data-item.
1005          *
1006          * This should really be handled by PHP PostgreSQL module
1007          *
1008          * @since 1.19
1009          * @param $text   string: postgreql array returned in a text form like {a,b}
1010          * @param $output string
1011          * @param $limit  int
1012          * @param $offset int
1013          * @return string
1014          */
1015         function pg_array_parse( $text, &$output, $limit = false, $offset = 1 ) {
1016                 if( false === $limit ) {
1017                         $limit = strlen( $text )-1;
1018                         $output = array();
1019                 }
1020                 if( '{}' == $text ) {
1021                         return $output;
1022                 }
1023                 do {
1024                         if ( '{' != $text{$offset} ) {
1025                                 preg_match( "/(\\{?\"([^\"\\\\]|\\\\.)*\"|[^,{}]+)+([,}]+)/",
1026                                         $text, $match, 0, $offset );
1027                                 $offset += strlen( $match[0] );
1028                                 $output[] = ( '"' != $match[1]{0}
1029                                                 ? $match[1]
1030                                                 : stripcslashes( substr( $match[1], 1, -1 ) ) );
1031                                 if ( '},' == $match[3] ) {
1032                                         return $output;
1033                                 }
1034                         } else {
1035                                 $offset = $this->pg_array_parse( $text, $output, $limit, $offset+1 );
1036                         }
1037                 } while ( $limit > $offset );
1038                 return $output;
1039         }
1040
1041         /**
1042          * Return aggregated value function call
1043          */
1044         public function aggregateValue( $valuedata, $valuename = 'value' ) {
1045                 return $valuedata;
1046         }
1047
1048         /**
1049          * @return string wikitext of a link to the server software's web site
1050          */
1051         public static function getSoftwareLink() {
1052                 return '[http://www.postgresql.org/ PostgreSQL]';
1053         }
1054
1055
1056         /**
1057          * Return current schema (executes SELECT current_schema())
1058          * Needs transaction
1059          *
1060          * @since 1.19
1061          * @return string return default schema for the current session
1062          */
1063         function getCurrentSchema() {
1064                 $res = $this->query( "SELECT current_schema()", __METHOD__);
1065                 $row = $this->fetchRow( $res );
1066                 return $row[0];
1067         }
1068
1069         /**
1070          * Return list of schemas which are accessible without schema name
1071          * This is list does not contain magic keywords like "$user"
1072          * Needs transaction
1073          *
1074          * @seealso getSearchPath()
1075          * @seealso setSearchPath()
1076          * @since 1.19
1077          * @return array list of actual schemas for the current sesson
1078          */
1079         function getSchemas() {
1080                 $res = $this->query( "SELECT current_schemas(false)", __METHOD__);
1081                 $row = $this->fetchRow( $res );
1082                 $schemas = array();
1083                 /* PHP pgsql support does not support array type, "{a,b}" string is returned */
1084                 return $this->pg_array_parse($row[0], $schemas);
1085         }
1086
1087         /**
1088          * Return search patch for schemas
1089          * This is different from getSchemas() since it contain magic keywords
1090          * (like "$user").
1091          * Needs transaction
1092          *
1093          * @since 1.19
1094          * @return array how to search for table names schemas for the current user
1095          */
1096         function getSearchPath() {
1097                 $res = $this->query( "SHOW search_path", __METHOD__);
1098                 $row = $this->fetchRow( $res );
1099                 /* PostgreSQL returns SHOW values as strings */
1100                 return explode(",", $row[0]);
1101         }
1102
1103         /**
1104          * Update search_path, values should already be sanitized
1105          * Values may contain magic keywords like "$user"
1106          * @since 1.19
1107          *
1108          * @param $search_path array list of schemas to be searched by default
1109          */
1110         function setSearchPath( $search_path ) {
1111                 $this->query( "SET search_path = " . implode(", ", $search_path) );
1112         }
1113
1114         /**
1115          * Determine default schema for MediaWiki core
1116          * Adjust this session schema search path if desired schema exists
1117          * and is not alread there.
1118          *
1119          * We need to have name of the core schema stored to be able
1120          * to query database metadata.
1121          *
1122          * This will be also called by the installer after the schema is created
1123          *
1124          * @since 1.19
1125          * @param $desired_schema string
1126          */
1127         function determineCoreSchema( $desired_schema ) {
1128                 $this->begin( __METHOD__ );
1129                 if ( $this->schemaExists( $desired_schema ) ) {
1130                         if ( in_array( $desired_schema, $this->getSchemas() ) ) {
1131                                 $this->mCoreSchema = $desired_schema;
1132                                 wfDebug("Schema \"" . $desired_schema . "\" already in the search path\n");
1133                         } else {
1134                                 /**
1135                                  * Prepend our schema (e.g. 'mediawiki') in front
1136                                  * of the search path
1137                                  * Fixes bug 15816
1138                                  */
1139                                 $search_path = $this->getSearchPath();
1140                                 array_unshift( $search_path,
1141                                         $this->addIdentifierQuotes( $desired_schema ));
1142                                 $this->setSearchPath( $search_path );
1143                                 $this->mCoreSchema = $desired_schema;
1144                                 wfDebug("Schema \"" . $desired_schema . "\" added to the search path\n");
1145                         }
1146                 } else {
1147                         $this->mCoreSchema = $this->getCurrentSchema();
1148                         wfDebug("Schema \"" . $desired_schema . "\" not found, using current \"". $this->mCoreSchema ."\"\n");
1149                 }
1150                 /* Commit SET otherwise it will be rollbacked on error or IGNORE SELECT */
1151                 $this->commit( __METHOD__ );
1152         }
1153
1154         /**
1155          * Return schema name fore core MediaWiki tables
1156          *
1157          * @since 1.19
1158          * @return string core schema name
1159          */
1160         function getCoreSchema() {
1161                 return $this->mCoreSchema;
1162         }
1163
1164         /**
1165          * @return string Version information from the database
1166          */
1167         function getServerVersion() {
1168                 if ( !isset( $this->numeric_version ) ) {
1169                         $versionInfo = pg_version( $this->mConn );
1170                         if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
1171                                 // Old client, abort install
1172                                 $this->numeric_version = '7.3 or earlier';
1173                         } elseif ( isset( $versionInfo['server'] ) ) {
1174                                 // Normal client
1175                                 $this->numeric_version = $versionInfo['server'];
1176                         } else {
1177                                 // Bug 16937: broken pgsql extension from PHP<5.3
1178                                 $this->numeric_version = pg_parameter_status( $this->mConn, 'server_version' );
1179                         }
1180                 }
1181                 return $this->numeric_version;
1182         }
1183
1184         /**
1185          * Query whether a given relation exists (in the given schema, or the
1186          * default mw one if not given)
1187          * @return bool
1188          */
1189         function relationExists( $table, $types, $schema = false ) {
1190                 if ( !is_array( $types ) ) {
1191                         $types = array( $types );
1192                 }
1193                 if ( !$schema ) {
1194                         $schema = $this->getCoreSchema();
1195                 }
1196                 $table = $this->realTableName( $table, 'raw' );
1197                 $etable = $this->addQuotes( $table );
1198                 $eschema = $this->addQuotes( $schema );
1199                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
1200                         . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
1201                         . "AND c.relkind IN ('" . implode( "','", $types ) . "')";
1202                 $res = $this->query( $SQL );
1203                 $count = $res ? $res->numRows() : 0;
1204                 return (bool)$count;
1205         }
1206
1207         /**
1208          * For backward compatibility, this function checks both tables and
1209          * views.
1210          * @return bool
1211          */
1212         function tableExists( $table, $fname = __METHOD__, $schema = false ) {
1213                 return $this->relationExists( $table, array( 'r', 'v' ), $schema );
1214         }
1215
1216         function sequenceExists( $sequence, $schema = false ) {
1217                 return $this->relationExists( $sequence, 'S', $schema );
1218         }
1219
1220         function triggerExists( $table, $trigger ) {
1221                 $q = <<<SQL
1222         SELECT 1 FROM pg_class, pg_namespace, pg_trigger
1223                 WHERE relnamespace=pg_namespace.oid AND relkind='r'
1224                           AND tgrelid=pg_class.oid
1225                           AND nspname=%s AND relname=%s AND tgname=%s
1226 SQL;
1227                 $res = $this->query(
1228                         sprintf(
1229                                 $q,
1230                                 $this->addQuotes( $this->getCoreSchema() ),
1231                                 $this->addQuotes( $table ),
1232                                 $this->addQuotes( $trigger )
1233                         )
1234                 );
1235                 if ( !$res ) {
1236                         return null;
1237                 }
1238                 $rows = $res->numRows();
1239                 return $rows;
1240         }
1241
1242         function ruleExists( $table, $rule ) {
1243                 $exists = $this->selectField( 'pg_rules', 'rulename',
1244                         array(
1245                                 'rulename' => $rule,
1246                                 'tablename' => $table,
1247                                 'schemaname' => $this->getCoreSchema()
1248                         )
1249                 );
1250                 return $exists === $rule;
1251         }
1252
1253         function constraintExists( $table, $constraint ) {
1254                 $SQL = sprintf( "SELECT 1 FROM information_schema.table_constraints ".
1255                            "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
1256                         $this->addQuotes( $this->getCoreSchema() ),
1257                         $this->addQuotes( $table ),
1258                         $this->addQuotes( $constraint )
1259                 );
1260                 $res = $this->query( $SQL );
1261                 if ( !$res ) {
1262                         return null;
1263                 }
1264                 $rows = $res->numRows();
1265                 return $rows;
1266         }
1267
1268         /**
1269          * Query whether a given schema exists. Returns true if it does, false if it doesn't.
1270          * @return bool
1271          */
1272         function schemaExists( $schema ) {
1273                 $exists = $this->selectField( '"pg_catalog"."pg_namespace"', 1,
1274                         array( 'nspname' => $schema ), __METHOD__ );
1275                 return (bool)$exists;
1276         }
1277
1278         /**
1279          * Returns true if a given role (i.e. user) exists, false otherwise.
1280          * @return bool
1281          */
1282         function roleExists( $roleName ) {
1283                 $exists = $this->selectField( '"pg_catalog"."pg_roles"', 1,
1284                         array( 'rolname' => $roleName ), __METHOD__ );
1285                 return (bool)$exists;
1286         }
1287
1288         function fieldInfo( $table, $field ) {
1289                 return PostgresField::fromText( $this, $table, $field );
1290         }
1291
1292         /**
1293          * pg_field_type() wrapper
1294          * @return string
1295          */
1296         function fieldType( $res, $index ) {
1297                 if ( $res instanceof ResultWrapper ) {
1298                         $res = $res->result;
1299                 }
1300                 return pg_field_type( $res, $index );
1301         }
1302
1303         /**
1304          * @param $b
1305          * @return Blob
1306          */
1307         function encodeBlob( $b ) {
1308                 return new Blob( pg_escape_bytea( $this->mConn, $b ) );
1309         }
1310
1311         function decodeBlob( $b ) {
1312                 if ( $b instanceof Blob ) {
1313                         $b = $b->fetch();
1314                 }
1315                 return pg_unescape_bytea( $b );
1316         }
1317
1318         function strencode( $s ) { # Should not be called by us
1319                 return pg_escape_string( $this->mConn, $s );
1320         }
1321
1322         /**
1323          * @param $s null|bool|Blob
1324          * @return int|string
1325          */
1326         function addQuotes( $s ) {
1327                 if ( is_null( $s ) ) {
1328                         return 'NULL';
1329                 } elseif ( is_bool( $s ) ) {
1330                         return intval( $s );
1331                 } elseif ( $s instanceof Blob ) {
1332                         return "'" . $s->fetch( $s ) . "'";
1333                 }
1334                 return "'" . pg_escape_string( $this->mConn, $s ) . "'";
1335         }
1336
1337         /**
1338          * Postgres specific version of replaceVars.
1339          * Calls the parent version in Database.php
1340          *
1341          * @private
1342          *
1343          * @param $ins String: SQL string, read from a stream (usually tables.sql)
1344          *
1345          * @return string SQL string
1346          */
1347         protected function replaceVars( $ins ) {
1348                 $ins = parent::replaceVars( $ins );
1349
1350                 if ( $this->numeric_version >= 8.3 ) {
1351                         // Thanks for not providing backwards-compatibility, 8.3
1352                         $ins = preg_replace( "/to_tsvector\s*\(\s*'default'\s*,/", 'to_tsvector(', $ins );
1353                 }
1354
1355                 if ( $this->numeric_version <= 8.1 ) { // Our minimum version
1356                         $ins = str_replace( 'USING gin', 'USING gist', $ins );
1357                 }
1358
1359                 return $ins;
1360         }
1361
1362         /**
1363          * Various select options
1364          *
1365          * @private
1366          *
1367          * @param $options Array: an associative array of options to be turned into
1368          *              an SQL query, valid keys are listed in the function.
1369          * @return array
1370          */
1371         function makeSelectOptions( $options ) {
1372                 $preLimitTail = $postLimitTail = '';
1373                 $startOpts = $useIndex = '';
1374
1375                 $noKeyOptions = array();
1376                 foreach ( $options as $key => $option ) {
1377                         if ( is_numeric( $key ) ) {
1378                                 $noKeyOptions[$option] = true;
1379                         }
1380                 }
1381
1382                 if ( isset( $options['GROUP BY'] ) ) {
1383                         $gb = is_array( $options['GROUP BY'] )
1384                                 ? implode( ',', $options['GROUP BY'] )
1385                                 : $options['GROUP BY'];
1386                         $preLimitTail .= " GROUP BY {$gb}";
1387                 }
1388
1389                 if ( isset( $options['HAVING'] ) ) {
1390                         $preLimitTail .= " HAVING {$options['HAVING']}";
1391                 }
1392
1393                 if ( isset( $options['ORDER BY'] ) ) {
1394                         $ob = is_array( $options['ORDER BY'] )
1395                                 ? implode( ',', $options['ORDER BY'] )
1396                                 : $options['ORDER BY'];
1397                         $preLimitTail .= " ORDER BY {$ob}";
1398                 }
1399
1400                 //if ( isset( $options['LIMIT'] ) ) {
1401                 //      $tailOpts .= $this->limitResult( '', $options['LIMIT'],
1402                 //              isset( $options['OFFSET'] ) ? $options['OFFSET']
1403                 //              : false );
1404                 //}
1405
1406                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1407                         $postLimitTail .= ' FOR UPDATE';
1408                 }
1409                 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1410                         $startOpts .= 'DISTINCT';
1411                 }
1412
1413                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1414         }
1415
1416         function setFakeMaster( $enabled = true ) {}
1417
1418         function getDBname() {
1419                 return $this->mDBname;
1420         }
1421
1422         function getServer() {
1423                 return $this->mServer;
1424         }
1425
1426         function buildConcat( $stringList ) {
1427                 return implode( ' || ', $stringList );
1428         }
1429
1430         public function getSearchEngine() {
1431                 return 'SearchPostgres';
1432         }
1433
1434         public function streamStatementEnd( &$sql, &$newLine ) {
1435                 # Allow dollar quoting for function declarations
1436                 if ( substr( $newLine, 0, 4 ) == '$mw$' ) {
1437                         if ( $this->delimiter ) {
1438                                 $this->delimiter = false;
1439                         }
1440                         else {
1441                                 $this->delimiter = ';';
1442                         }
1443                 }
1444                 return parent::streamStatementEnd( $sql, $newLine );
1445         }
1446 } // end DatabasePostgres class