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                 $this->connectString = $this->makeConnectionString( $connectVars, PGSQL_CONNECT_FORCE_NEW );
 360                 $this->close();
 361                 $this->installErrorHandler();
 362                 $this->mConn = pg_connect( $this->connectString );
 363                 $phpError = $this->restoreErrorHandler();
 364
 365                 if ( !$this->mConn ) {
 366                         wfDebug( "DB connection error\n" );
 367                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
 368                         wfDebug( $this->lastError() . "\n" );
 369                         throw new DBConnectionError( $this, str_replace( "\n", ' ', $phpError ) );
 370                 }
 371
 372                 $this->mOpened = true;
 373                 $this->mTransactionState = new PostgresTransactionState( $this->mConn );
 374
 375                 global $wgCommandLineMode;
 376                 # If called from the command-line (e.g. importDump), only show errors
 377                 if ( $wgCommandLineMode ) {
 378                         $this->doQuery( "SET client_min_messages = 'ERROR'" );
 379                 }
 380
 381                 $this->query( "SET client_encoding='UTF8'", __METHOD__ );
 382                 $this->query( "SET datestyle = 'ISO, YMD'", __METHOD__ );
 383                 $this->query( "SET timezone = 'GMT'", __METHOD__ );
 384                 $this->query( "SET standard_conforming_strings = on", __METHOD__ );
 385
 386                 global $wgDBmwschema;
 387                 $this->determineCoreSchema( $wgDBmwschema );
 388
 389                 return $this->mConn;
 390         }
 391
 392         /**
 393          * Postgres doesn't support selectDB in the same way MySQL does. So if the
 394          * DB name doesn't match the open connection, open a new one
 395          * @return
 396          */
 397         function selectDB( $db ) {
 398                 if ( $this->mDBname !== $db ) {
 399                         return (bool)$this->open( $this->mServer, $this->mUser, $this->mPassword, $db );
 400                 } else {
 401                         return true;
 402                 }
 403         }
 404
 405         function makeConnectionString( $vars ) {
 406                 $s = '';
 407                 foreach ( $vars as $name => $value ) {
 408                         $s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
 409                 }
 410                 return $s;
 411         }
 412
 413         /**
 414          * Closes a database connection, if it is open
 415          * Returns success, true if already closed
 416          * @return bool
 417          */
 418         protected function closeConnection() {
 419                 return pg_close( $this->mConn );
 420         }
 421
 422         public function doQuery( $sql ) {
 423                 if ( function_exists( 'mb_convert_encoding' ) ) {
 424                         $sql = mb_convert_encoding( $sql, 'UTF-8' );
 425                 }
 426                 $this->mTransactionState->check();
 427                 if( pg_send_query( $this->mConn, $sql ) === false ) {
 428                         throw new DBUnexpectedError( $this, "Unable to post new query to PostgreSQL\n" );
 429                 }
 430                 $this->mLastResult = pg_get_result( $this->mConn );
 431                 $this->mTransactionState->check();
 432                 $this->mAffectedRows = null;
 433                 if ( pg_result_error( $this->mLastResult ) ) {
 434                         return false;
 435                 }
 436                 return $this->mLastResult;
 437         }
 438
 439         protected function dumpError () {
 440                 $diags = array( PGSQL_DIAG_SEVERITY,
 441                                 PGSQL_DIAG_SQLSTATE,
 442                                 PGSQL_DIAG_MESSAGE_PRIMARY,
 443                                 PGSQL_DIAG_MESSAGE_DETAIL,
 444                                 PGSQL_DIAG_MESSAGE_HINT,
 445                                 PGSQL_DIAG_STATEMENT_POSITION,
 446                                 PGSQL_DIAG_INTERNAL_POSITION,
 447                                 PGSQL_DIAG_INTERNAL_QUERY,
 448                                 PGSQL_DIAG_CONTEXT,
 449                                 PGSQL_DIAG_SOURCE_FILE,
 450                                 PGSQL_DIAG_SOURCE_LINE,
 451                                 PGSQL_DIAG_SOURCE_FUNCTION );
 452                 foreach ( $diags as $d ) {
 453                         wfDebug( sprintf("PgSQL ERROR(%d): %s\n", $d, pg_result_error_field( $this->mLastResult, $d ) ) );
 454                 }
 455         }
 456
 457         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 458                 /* Transaction stays in the ERROR state until rolledback */
 459                 if ( $tempIgnore ) {
 460                         /* Check for constraint violation */
 461                         if ( $errno === '23505' ) {
 462                                 parent::reportQueryError( $error, $errno, $sql, $fname, $tempIgnore );
 463                                 return;
 464                         }
 465                 }
 466                 /* Don't ignore serious errors */
 467                 $this->rollback( __METHOD__ );
 468                 parent::reportQueryError( $error, $errno, $sql, $fname, false );
 469         }
 470
 471
 472         function queryIgnore( $sql, $fname = 'DatabasePostgres::queryIgnore' ) {
 473                 return $this->query( $sql, $fname, true );
 474         }
 475
 476         function freeResult( $res ) {
 477                 if ( $res instanceof ResultWrapper ) {
 478                         $res = $res->result;
 479                 }
 480                 wfSuppressWarnings();
 481                 $ok = pg_free_result( $res );
 482                 wfRestoreWarnings();
 483                 if ( !$ok ) {
 484                         throw new DBUnexpectedError( $this, "Unable to free Postgres result\n" );
 485                 }
 486         }
 487
 488         function fetchObject( $res ) {
 489                 if ( $res instanceof ResultWrapper ) {
 490                         $res = $res->result;
 491                 }
 492                 wfSuppressWarnings();
 493                 $row = pg_fetch_object( $res );
 494                 wfRestoreWarnings();
 495                 # @todo FIXME: HACK HACK HACK HACK debug
 496
 497                 # @todo hashar: not sure if the following test really trigger if the object
 498                 #          fetching failed.
 499                 if( pg_last_error( $this->mConn ) ) {
 500                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 501                 }
 502                 return $row;
 503         }
 504
 505         function fetchRow( $res ) {
 506                 if ( $res instanceof ResultWrapper ) {
 507                         $res = $res->result;
 508                 }
 509                 wfSuppressWarnings();
 510                 $row = pg_fetch_array( $res );
 511                 wfRestoreWarnings();
 512                 if( pg_last_error( $this->mConn ) ) {
 513                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 514                 }
 515                 return $row;
 516         }
 517
 518         function numRows( $res ) {
 519                 if ( $res instanceof ResultWrapper ) {
 520                         $res = $res->result;
 521                 }
 522                 wfSuppressWarnings();
 523                 $n = pg_num_rows( $res );
 524                 wfRestoreWarnings();
 525                 if( pg_last_error( $this->mConn ) ) {
 526                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 527                 }
 528                 return $n;
 529         }
 530
 531         function numFields( $res ) {
 532                 if ( $res instanceof ResultWrapper ) {
 533                         $res = $res->result;
 534                 }
 535                 return pg_num_fields( $res );
 536         }
 537
 538         function fieldName( $res, $n ) {
 539                 if ( $res instanceof ResultWrapper ) {
 540                         $res = $res->result;
 541                 }
 542                 return pg_field_name( $res, $n );
 543         }
 544
 545         /**
 546          * This must be called after nextSequenceVal
 547          * @return null
 548          */
 549         function insertId() {
 550                 return $this->mInsertId;
 551         }
 552
 553         function dataSeek( $res, $row ) {
 554                 if ( $res instanceof ResultWrapper ) {
 555                         $res = $res->result;
 556                 }
 557                 return pg_result_seek( $res, $row );
 558         }
 559
 560         function lastError() {
 561                 if ( $this->mConn ) {
 562                         if ( $this->mLastResult ) {
 563                                 return pg_result_error( $this->mLastResult );
 564                         } else {
 565                                 return pg_last_error();
 566                         }
 567                 } else {
 568                         return 'No database connection';
 569                 }
 570         }
 571         function lastErrno() {
 572                 if ( $this->mLastResult ) {
 573                         return pg_result_error_field( $this->mLastResult, PGSQL_DIAG_SQLSTATE );
 574                 } else {
 575                         return false;
 576                 }
 577         }
 578
 579         function affectedRows() {
 580                 if ( !is_null( $this->mAffectedRows ) ) {
 581                         // Forced result for simulated queries
 582                         return $this->mAffectedRows;
 583                 }
 584                 if( empty( $this->mLastResult ) ) {
 585                         return 0;
 586                 }
 587                 return pg_affected_rows( $this->mLastResult );
 588         }
 589
 590         /**
 591          * Estimate rows in dataset
 592          * Returns estimated count, based on EXPLAIN output
 593          * This is not necessarily an accurate estimate, so use sparingly
 594          * Returns -1 if count cannot be found
 595          * Takes same arguments as Database::select()
 596          * @return int
 597          */
 598         function estimateRowCount( $table, $vars = '*', $conds='', $fname = 'DatabasePostgres::estimateRowCount', $options = array() ) {
 599                 $options['EXPLAIN'] = true;
 600                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 601                 $rows = -1;
 602                 if ( $res ) {
 603                         $row = $this->fetchRow( $res );
 604                         $count = array();
 605                         if( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
 606                                 $rows = $count[1];
 607                         }
 608                 }
 609                 return $rows;
 610         }
 611
 612         /**
 613          * Returns information about an index
 614          * If errors are explicitly ignored, returns NULL on failure
 615          * @return bool|null
 616          */
 617         function indexInfo( $table, $index, $fname = 'DatabasePostgres::indexInfo' ) {
 618                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 619                 $res = $this->query( $sql, $fname );
 620                 if ( !$res ) {
 621                         return null;
 622                 }
 623                 foreach ( $res as $row ) {
 624                         if ( $row->indexname == $this->indexName( $index ) ) {
 625                                 return $row;
 626                         }
 627                 }
 628                 return false;
 629         }
 630
 631         /**
 632          * Returns is of attributes used in index
 633          *
 634          * @since 1.19
 635          * @return Array
 636          */
 637         function indexAttributes ( $index, $schema = false ) {
 638                 if ( $schema === false )
 639                         $schema = $this->getCoreSchema();
 640                 /*
 641                  * A subquery would be not needed if we didn't care about the order
 642                  * of attributes, but we do
 643                  */
 644                 $sql = <<<__INDEXATTR__
 645
 646                         SELECT opcname,
 647                                 attname,
 648                                 i.indoption[s.g] as option,
 649                                 pg_am.amname
 650                         FROM
 651                                 (SELECT generate_series(array_lower(isub.indkey,1), array_upper(isub.indkey,1)) AS g
 652                                         FROM
 653                                                 pg_index isub
 654                                         JOIN pg_class cis
 655                                                 ON cis.oid=isub.indexrelid
 656                                         JOIN pg_namespace ns
 657                                                 ON cis.relnamespace = ns.oid
 658                                         WHERE cis.relname='$index' AND ns.nspname='$schema') AS s,
 659                                 pg_attribute,
 660                                 pg_opclass opcls,
 661                                 pg_am,
 662                                 pg_class ci
 663                                 JOIN pg_index i
 664                                         ON ci.oid=i.indexrelid
 665                                 JOIN pg_class ct
 666                                         ON ct.oid = i.indrelid
 667                                 JOIN pg_namespace n
 668                                         ON ci.relnamespace = n.oid
 669                                 WHERE
 670                                         ci.relname='$index' AND n.nspname='$schema'
 671                                         AND     attrelid = ct.oid
 672                                         AND     i.indkey[s.g] = attnum
 673                                         AND     i.indclass[s.g] = opcls.oid
 674                                         AND     pg_am.oid = opcls.opcmethod
 675 __INDEXATTR__;
 676                 $res = $this->query($sql, __METHOD__);
 677                 $a = array();
 678                 if ( $res ) {
 679                         foreach ( $res as $row ) {
 680                                 $a[] = array(
 681                                         $row->attname,
 682                                         $row->opcname,
 683                                         $row->amname,
 684                                         $row->option);
 685                         }
 686                 } else {
 687                         return null;
 688                 }
 689                 return $a;
 690         }
 691
 692
 693         function indexUnique( $table, $index, $fname = 'DatabasePostgres::indexUnique' ) {
 694                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 695                         " AND indexdef LIKE 'CREATE UNIQUE%(" .
 696                         $this->strencode( $this->indexName( $index ) ) .
 697                         ")'";
 698                 $res = $this->query( $sql, $fname );
 699                 if ( !$res ) {
 700                         return null;
 701                 }
 702                 foreach ( $res as $row ) {
 703                         return true;
 704                 }
 705                 return false;
 706         }
 707
 708         /**
 709          * INSERT wrapper, inserts an array into a table
 710          *
 711          * $args may be a single associative array, or an array of these with numeric keys,
 712          * for multi-row insert (Postgres version 8.2 and above only).
 713          *
 714          * @param $table   String: Name of the table to insert to.
 715          * @param $args    Array: Items to insert into the table.
 716          * @param $fname   String: Name of the function, for profiling
 717          * @param $options String or Array. Valid options: IGNORE
 718          *
 719          * @return bool Success of insert operation. IGNORE always returns true.
 720          */
 721         function insert( $table, $args, $fname = 'DatabasePostgres::insert', $options = array() ) {
 722                 if ( !count( $args ) ) {
 723                         return true;
 724                 }
 725
 726                 $table = $this->tableName( $table );
 727                 if (! isset( $this->numeric_version ) ) {
 728                         $this->getServerVersion();
 729                 }
 730
 731                 if ( !is_array( $options ) ) {
 732                         $options = array( $options );
 733                 }
 734
 735                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 736                         $multi = true;
 737                         $keys = array_keys( $args[0] );
 738                 } else {
 739                         $multi = false;
 740                         $keys = array_keys( $args );
 741                 }
 742
 743                 // If IGNORE is set, we use savepoints to emulate mysql's behavior
 744                 $savepoint = null;
 745                 if ( in_array( 'IGNORE', $options ) ) {
 746                         $savepoint = new SavepointPostgres( $this, 'mw' );
 747                         $olde = error_reporting( 0 );
 748                         // For future use, we may want to track the number of actual inserts
 749                         // Right now, insert (all writes) simply return true/false
 750                         $numrowsinserted = 0;
 751                 }
 752
 753                 $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 754
 755                 if ( $multi ) {
 756                         if ( $this->numeric_version >= 8.2 && !$savepoint ) {
 757                                 $first = true;
 758                                 foreach ( $args as $row ) {
 759                                         if ( $first ) {
 760                                                 $first = false;
 761                                         } else {
 762                                                 $sql .= ',';
 763                                         }
 764                                         $sql .= '(' . $this->makeList( $row ) . ')';
 765                                 }
 766                                 $res = (bool)$this->query( $sql, $fname, $savepoint );
 767                         } else {
 768                                 $res = true;
 769                                 $origsql = $sql;
 770                                 foreach ( $args as $row ) {
 771                                         $tempsql = $origsql;
 772                                         $tempsql .= '(' . $this->makeList( $row ) . ')';
 773
 774                                         if ( $savepoint ) {
 775                                                 $savepoint->savepoint();
 776                                         }
 777
 778                                         $tempres = (bool)$this->query( $tempsql, $fname, $savepoint );
 779
 780                                         if ( $savepoint ) {
 781                                                 $bar = pg_last_error();
 782                                                 if ( $bar != false ) {
 783                                                         $savepoint->rollback();
 784                                                 } else {
 785                                                         $savepoint->release();
 786                                                         $numrowsinserted++;
 787                                                 }
 788                                         }
 789
 790                                         // If any of them fail, we fail overall for this function call
 791                                         // Note that this will be ignored if IGNORE is set
 792                                         if ( !$tempres ) {
 793                                                 $res = false;
 794                                         }
 795                                 }
 796                         }
 797                 } else {
 798                         // Not multi, just a lone insert
 799                         if ( $savepoint ) {
 800                                 $savepoint->savepoint();
 801                         }
 802
 803                         $sql .= '(' . $this->makeList( $args ) . ')';
 804                         $res = (bool)$this->query( $sql, $fname, $savepoint );
 805                         if ( $savepoint ) {
 806                                 $bar = pg_last_error();
 807                                 if ( $bar != false ) {
 808                                         $savepoint->rollback();
 809                                 } else {
 810                                         $savepoint->release();
 811                                         $numrowsinserted++;
 812                                 }
 813                         }
 814                 }
 815                 if ( $savepoint ) {
 816                         $olde = error_reporting( $olde );
 817                         $savepoint->commit();
 818
 819                         // Set the affected row count for the whole operation
 820                         $this->mAffectedRows = $numrowsinserted;
 821
 822                         // IGNORE always returns true
 823                         return true;
 824                 }
 825
 826                 return $res;
 827         }
 828
 829         /**
 830          * INSERT SELECT wrapper
 831          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
 832          * Source items may be literals rather then field names, but strings should be quoted with Database::addQuotes()
 833          * $conds may be "*" to copy the whole table
 834          * srcTable may be an array of tables.
 835          * @todo FIXME: Implement this a little better (seperate select/insert)?
 836          * @return bool
 837          */
 838         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'DatabasePostgres::insertSelect',
 839                 $insertOptions = array(), $selectOptions = array() )
 840         {
 841                 $destTable = $this->tableName( $destTable );
 842
 843                 if( !is_array( $insertOptions ) ) {
 844                         $insertOptions = array( $insertOptions );
 845                 }
 846
 847                 /*
 848                  * If IGNORE is set, we use savepoints to emulate mysql's behavior
 849                  * Ignore LOW PRIORITY option, since it is MySQL-specific
 850                  */
 851                 $savepoint = null;
 852                 if ( in_array( 'IGNORE', $insertOptions ) ) {
 853                         $savepoint = new SavepointPostgres( $this, 'mw' );
 854                         $olde = error_reporting( 0 );
 855                         $numrowsinserted = 0;
 856                         $savepoint->savepoint();
 857                 }
 858
 859                 if( !is_array( $selectOptions ) ) {
 860                         $selectOptions = array( $selectOptions );
 861                 }
 862                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
 863                 if( is_array( $srcTable ) ) {
 864                         $srcTable = implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
 865                 } else {
 866                         $srcTable = $this->tableName( $srcTable );
 867                 }
 868
 869                 $sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
 870                                 " SELECT $startOpts " . implode( ',', $varMap ) .
 871                                 " FROM $srcTable $useIndex";
 872
 873                 if ( $conds != '*' ) {
 874                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
 875                 }
 876
 877                 $sql .= " $tailOpts";
 878
 879                 $res = (bool)$this->query( $sql, $fname, $savepoint );
 880                 if( $savepoint ) {
 881                         $bar = pg_last_error();
 882                         if( $bar != false ) {
 883                                 $savepoint->rollback();
 884                         } else {
 885                                 $savepoint->release();
 886                                 $numrowsinserted++;
 887                         }
 888                         $olde = error_reporting( $olde );
 889                         $savepoint->commit();
 890
 891                         // Set the affected row count for the whole operation
 892                         $this->mAffectedRows = $numrowsinserted;
 893
 894                         // IGNORE always returns true
 895                         return true;
 896                 }
 897
 898                 return $res;
 899         }
 900
 901         function tableName( $name, $format = 'quoted' ) {
 902                 # Replace reserved words with better ones
 903                 switch( $name ) {
 904                         case 'user':
 905                                 return $this->realTableName( 'mwuser', $format );
 906                         case 'text':
 907                                 return $this->realTableName( 'pagecontent', $format );
 908                         default:
 909                                 return $this->realTableName( $name, $format );
 910                 }
 911         }
 912
 913         /* Don't cheat on installer */
 914         function realTableName( $name, $format = 'quoted' ) {
 915                 return parent::tableName( $name, $format );
 916         }
 917
 918         /**
 919          * Return the next in a sequence, save the value for retrieval via insertId()
 920          * @return null
 921          */
 922         function nextSequenceValue( $seqName ) {
 923                 $safeseq = str_replace( "'", "''", $seqName );
 924                 $res = $this->query( "SELECT nextval('$safeseq')" );
 925                 $row = $this->fetchRow( $res );
 926                 $this->mInsertId = $row[0];
 927                 return $this->mInsertId;
 928         }
 929
 930         /**
 931          * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
 932          * @return
 933          */
 934         function currentSequenceValue( $seqName ) {
 935                 $safeseq = str_replace( "'", "''", $seqName );
 936                 $res = $this->query( "SELECT currval('$safeseq')" );
 937                 $row = $this->fetchRow( $res );
 938                 $currval = $row[0];
 939                 return $currval;
 940         }
 941
 942         # Returns the size of a text field, or -1 for "unlimited"
 943         function textFieldSize( $table, $field ) {
 944                 $table = $this->tableName( $table );
 945                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
 946                         FROM pg_class c, pg_attribute a, pg_type t
 947                         WHERE relname='$table' AND a.attrelid=c.oid AND
 948                                 a.atttypid=t.oid and a.attname='$field'";
 949                 $res =$this->query( $sql );
 950                 $row = $this->fetchObject( $res );
 951                 if ( $row->ftype == 'varchar' ) {
 952                         $size = $row->size - 4;
 953                 } else {
 954                         $size = $row->size;
 955                 }
 956                 return $size;
 957         }
 958
 959         function limitResult( $sql, $limit, $offset = false ) {
 960                 return "$sql LIMIT $limit " . ( is_numeric( $offset ) ? " OFFSET {$offset} " : '' );
 961         }
 962
 963         function wasDeadlock() {
 964                 return $this->lastErrno() == '40P01';
 965         }
 966
 967         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabasePostgres::duplicateTableStructure' ) {
 968                 $newName = $this->addIdentifierQuotes( $newName );
 969                 $oldName = $this->addIdentifierQuotes( $oldName );
 970                 return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName (LIKE $oldName INCLUDING DEFAULTS)", $fname );
 971         }
 972
 973         function listTables( $prefix = null, $fname = 'DatabasePostgres::listTables' ) {
 974                 $eschema = $this->addQuotes( $this->getCoreSchema() );
 975                 $result = $this->query( "SELECT tablename FROM pg_tables WHERE schemaname = $eschema", $fname );
 976                 $endArray = array();
 977
 978                 foreach( $result as $table ) {
 979                         $vars = get_object_vars($table);
 980                         $table = array_pop( $vars );
 981                         if( !$prefix || strpos( $table, $prefix ) === 0 ) {
 982                                 $endArray[] = $table;
 983                         }
 984                 }
 985
 986                 return $endArray;
 987         }
 988
 989         function timestamp( $ts = 0 ) {
 990                 return wfTimestamp( TS_POSTGRES, $ts );
 991         }
 992
 993         /*
 994          * Posted by cc[plus]php[at]c2se[dot]com on 25-Mar-2009 09:12
 995          * to http://www.php.net/manual/en/ref.pgsql.php
 996          *
 997          * Parsing a postgres array can be a tricky problem, he's my
 998          * take on this, it handles multi-dimensional arrays plus
 999          * escaping using a nasty regexp to determine the limits of each
1000          * data-item.
1001          *
1002          * This should really be handled by PHP PostgreSQL module
1003          *
1004          * @since 1.19
1005          * @param $text   string: postgreql array returned in a text form like {a,b}
1006          * @param $output string
1007          * @param $limit  int
1008          * @param $offset int
1009          * @return string
1010          */
1011         function pg_array_parse( $text, &$output, $limit = false, $offset = 1 ) {
1012                 if( false === $limit ) {
1013                         $limit = strlen( $text )-1;
1014                         $output = array();
1015                 }
1016                 if( '{}' == $text ) {
1017                         return $output;
1018                 }
1019                 do {
1020                         if ( '{' != $text{$offset} ) {
1021                                 preg_match( "/(\\{?\"([^\"\\\\]|\\\\.)*\"|[^,{}]+)+([,}]+)/",
1022                                         $text, $match, 0, $offset );
1023                                 $offset += strlen( $match[0] );
1024                                 $output[] = ( '"' != $match[1]{0}
1025                                                 ? $match[1]
1026                                                 : stripcslashes( substr( $match[1], 1, -1 ) ) );
1027                                 if ( '},' == $match[3] ) {
1028                                         return $output;
1029                                 }
1030                         } else {
1031                                 $offset = $this->pg_array_parse( $text, $output, $limit, $offset+1 );
1032                         }
1033                 } while ( $limit > $offset );
1034                 return $output;
1035         }
1036
1037         /**
1038          * Return aggregated value function call
1039          */
1040         public function aggregateValue( $valuedata, $valuename = 'value' ) {
1041                 return $valuedata;
1042         }
1043
1044         /**
1045          * @return string wikitext of a link to the server software's web site
1046          */
1047         public static function getSoftwareLink() {
1048                 return '[http://www.postgresql.org/ PostgreSQL]';
1049         }
1050
1051
1052         /**
1053          * Return current schema (executes SELECT current_schema())
1054          * Needs transaction
1055          *
1056          * @since 1.19
1057          * @return string return default schema for the current session
1058          */
1059         function getCurrentSchema() {
1060                 $res = $this->query( "SELECT current_schema()", __METHOD__);
1061                 $row = $this->fetchRow( $res );
1062                 return $row[0];
1063         }
1064
1065         /**
1066          * Return list of schemas which are accessible without schema name
1067          * This is list does not contain magic keywords like "$user"
1068          * Needs transaction
1069          *
1070          * @seealso getSearchPath()
1071          * @seealso setSearchPath()
1072          * @since 1.19
1073          * @return array list of actual schemas for the current sesson
1074          */
1075         function getSchemas() {
1076                 $res = $this->query( "SELECT current_schemas(false)", __METHOD__);
1077                 $row = $this->fetchRow( $res );
1078                 $schemas = array();
1079                 /* PHP pgsql support does not support array type, "{a,b}" string is returned */
1080                 return $this->pg_array_parse($row[0], $schemas);
1081         }
1082
1083         /**
1084          * Return search patch for schemas
1085          * This is different from getSchemas() since it contain magic keywords
1086          * (like "$user").
1087          * Needs transaction
1088          *
1089          * @since 1.19
1090          * @return array how to search for table names schemas for the current user
1091          */
1092         function getSearchPath() {
1093                 $res = $this->query( "SHOW search_path", __METHOD__);
1094                 $row = $this->fetchRow( $res );
1095                 /* PostgreSQL returns SHOW values as strings */
1096                 return explode(",", $row[0]);
1097         }
1098
1099         /**
1100          * Update search_path, values should already be sanitized
1101          * Values may contain magic keywords like "$user"
1102          * @since 1.19
1103          *
1104          * @param $search_path array list of schemas to be searched by default
1105          */
1106         function setSearchPath( $search_path ) {
1107                 $this->query( "SET search_path = " . implode(", ", $search_path) );
1108         }
1109
1110         /**
1111          * Determine default schema for MediaWiki core
1112          * Adjust this session schema search path if desired schema exists
1113          * and is not alread there.
1114          *
1115          * We need to have name of the core schema stored to be able
1116          * to query database metadata.
1117          *
1118          * This will be also called by the installer after the schema is created
1119          *
1120          * @since 1.19
1121          * @param $desired_schema string
1122          */
1123         function determineCoreSchema( $desired_schema ) {
1124                 $this->begin( __METHOD__ );
1125                 if ( $this->schemaExists( $desired_schema ) ) {
1126                         if ( in_array( $desired_schema, $this->getSchemas() ) ) {
1127                                 $this->mCoreSchema = $desired_schema;
1128                                 wfDebug("Schema \"" . $desired_schema . "\" already in the search path\n");
1129                         } else {
1130                                 /**
1131                                  * Prepend our schema (e.g. 'mediawiki') in front
1132                                  * of the search path
1133                                  * Fixes bug 15816
1134                                  */
1135                                 $search_path = $this->getSearchPath();
1136                                 array_unshift( $search_path,
1137                                         $this->addIdentifierQuotes( $desired_schema ));
1138                                 $this->setSearchPath( $search_path );
1139                                 $this->mCoreSchema = $desired_schema;
1140                                 wfDebug("Schema \"" . $desired_schema . "\" added to the search path\n");
1141                         }
1142                 } else {
1143                         $this->mCoreSchema = $this->getCurrentSchema();
1144                         wfDebug("Schema \"" . $desired_schema . "\" not found, using current \"". $this->mCoreSchema ."\"\n");
1145                 }
1146                 /* Commit SET otherwise it will be rollbacked on error or IGNORE SELECT */
1147                 $this->commit( __METHOD__ );
1148         }
1149
1150         /**
1151          * Return schema name fore core MediaWiki tables
1152          *
1153          * @since 1.19
1154          * @return string core schema name
1155          */
1156         function getCoreSchema() {
1157                 return $this->mCoreSchema;
1158         }
1159
1160         /**
1161          * @return string Version information from the database
1162          */
1163         function getServerVersion() {
1164                 if ( !isset( $this->numeric_version ) ) {
1165                         $versionInfo = pg_version( $this->mConn );
1166                         if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
1167                                 // Old client, abort install
1168                                 $this->numeric_version = '7.3 or earlier';
1169                         } elseif ( isset( $versionInfo['server'] ) ) {
1170                                 // Normal client
1171                                 $this->numeric_version = $versionInfo['server'];
1172                         } else {
1173                                 // Bug 16937: broken pgsql extension from PHP<5.3
1174                                 $this->numeric_version = pg_parameter_status( $this->mConn, 'server_version' );
1175                         }
1176                 }
1177                 return $this->numeric_version;
1178         }
1179
1180         /**
1181          * Query whether a given relation exists (in the given schema, or the
1182          * default mw one if not given)
1183          * @return bool
1184          */
1185         function relationExists( $table, $types, $schema = false ) {
1186                 if ( !is_array( $types ) ) {
1187                         $types = array( $types );
1188                 }
1189                 if ( !$schema ) {
1190                         $schema = $this->getCoreSchema();
1191                 }
1192                 $table = $this->realTableName( $table, 'raw' );
1193                 $etable = $this->addQuotes( $table );
1194                 $eschema = $this->addQuotes( $schema );
1195                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
1196                         . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
1197                         . "AND c.relkind IN ('" . implode( "','", $types ) . "')";
1198                 $res = $this->query( $SQL );
1199                 $count = $res ? $res->numRows() : 0;
1200                 return (bool)$count;
1201         }
1202
1203         /**
1204          * For backward compatibility, this function checks both tables and
1205          * views.
1206          * @return bool
1207          */
1208         function tableExists( $table, $fname = __METHOD__, $schema = false ) {
1209                 return $this->relationExists( $table, array( 'r', 'v' ), $schema );
1210         }
1211
1212         function sequenceExists( $sequence, $schema = false ) {
1213                 return $this->relationExists( $sequence, 'S', $schema );
1214         }
1215
1216         function triggerExists( $table, $trigger ) {
1217                 $q = <<<SQL
1218         SELECT 1 FROM pg_class, pg_namespace, pg_trigger
1219                 WHERE relnamespace=pg_namespace.oid AND relkind='r'
1220                           AND tgrelid=pg_class.oid
1221                           AND nspname=%s AND relname=%s AND tgname=%s
1222 SQL;
1223                 $res = $this->query(
1224                         sprintf(
1225                                 $q,
1226                                 $this->addQuotes( $this->getCoreSchema() ),
1227                                 $this->addQuotes( $table ),
1228                                 $this->addQuotes( $trigger )
1229                         )
1230                 );
1231                 if ( !$res ) {
1232                         return null;
1233                 }
1234                 $rows = $res->numRows();
1235                 return $rows;
1236         }
1237
1238         function ruleExists( $table, $rule ) {
1239                 $exists = $this->selectField( 'pg_rules', 'rulename',
1240                         array(
1241                                 'rulename' => $rule,
1242                                 'tablename' => $table,
1243                                 'schemaname' => $this->getCoreSchema()
1244                         )
1245                 );
1246                 return $exists === $rule;
1247         }
1248
1249         function constraintExists( $table, $constraint ) {
1250                 $SQL = sprintf( "SELECT 1 FROM information_schema.table_constraints ".
1251                            "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
1252                         $this->addQuotes( $this->getCoreSchema() ),
1253                         $this->addQuotes( $table ),
1254                         $this->addQuotes( $constraint )
1255                 );
1256                 $res = $this->query( $SQL );
1257                 if ( !$res ) {
1258                         return null;
1259                 }
1260                 $rows = $res->numRows();
1261                 return $rows;
1262         }
1263
1264         /**
1265          * Query whether a given schema exists. Returns true if it does, false if it doesn't.
1266          * @return bool
1267          */
1268         function schemaExists( $schema ) {
1269                 $exists = $this->selectField( '"pg_catalog"."pg_namespace"', 1,
1270                         array( 'nspname' => $schema ), __METHOD__ );
1271                 return (bool)$exists;
1272         }
1273
1274         /**
1275          * Returns true if a given role (i.e. user) exists, false otherwise.
1276          * @return bool
1277          */
1278         function roleExists( $roleName ) {
1279                 $exists = $this->selectField( '"pg_catalog"."pg_roles"', 1,
1280                         array( 'rolname' => $roleName ), __METHOD__ );
1281                 return (bool)$exists;
1282         }
1283
1284         function fieldInfo( $table, $field ) {
1285                 return PostgresField::fromText( $this, $table, $field );
1286         }
1287
1288         /**
1289          * pg_field_type() wrapper
1290          * @return string
1291          */
1292         function fieldType( $res, $index ) {
1293                 if ( $res instanceof ResultWrapper ) {
1294                         $res = $res->result;
1295                 }
1296                 return pg_field_type( $res, $index );
1297         }
1298
1299         /* Not even sure why this is used in the main codebase... */
1300         function limitResultForUpdate( $sql, $num ) {
1301                 return $sql;
1302         }
1303
1304         /**
1305          * @param $b
1306          * @return Blob
1307          */
1308         function encodeBlob( $b ) {
1309                 return new Blob( pg_escape_bytea( $this->mConn, $b ) );
1310         }
1311
1312         function decodeBlob( $b ) {
1313                 if ( $b instanceof Blob ) {
1314                         $b = $b->fetch();
1315                 }
1316                 return pg_unescape_bytea( $b );
1317         }
1318
1319         function strencode( $s ) { # Should not be called by us
1320                 return pg_escape_string( $this->mConn, $s );
1321         }
1322
1323         /**
1324          * @param $s null|bool|Blob
1325          * @return int|string
1326          */
1327         function addQuotes( $s ) {
1328                 if ( is_null( $s ) ) {
1329                         return 'NULL';
1330                 } elseif ( is_bool( $s ) ) {
1331                         return intval( $s );
1332                 } elseif ( $s instanceof Blob ) {
1333                         return "'" . $s->fetch( $s ) . "'";
1334                 }
1335                 return "'" . pg_escape_string( $this->mConn, $s ) . "'";
1336         }
1337
1338         /**
1339          * Postgres specific version of replaceVars.
1340          * Calls the parent version in Database.php
1341          *
1342          * @private
1343          *
1344          * @param $ins String: SQL string, read from a stream (usually tables.sql)
1345          *
1346          * @return string SQL string
1347          */
1348         protected function replaceVars( $ins ) {
1349                 $ins = parent::replaceVars( $ins );
1350
1351                 if ( $this->numeric_version >= 8.3 ) {
1352                         // Thanks for not providing backwards-compatibility, 8.3
1353                         $ins = preg_replace( "/to_tsvector\s*\(\s*'default'\s*,/", 'to_tsvector(', $ins );
1354                 }
1355
1356                 if ( $this->numeric_version <= 8.1 ) { // Our minimum version
1357                         $ins = str_replace( 'USING gin', 'USING gist', $ins );
1358                 }
1359
1360                 return $ins;
1361         }
1362
1363         /**
1364          * Various select options
1365          *
1366          * @private
1367          *
1368          * @param $options Array: an associative array of options to be turned into
1369          *              an SQL query, valid keys are listed in the function.
1370          * @return array
1371          */
1372         function makeSelectOptions( $options ) {
1373                 $preLimitTail = $postLimitTail = '';
1374                 $startOpts = $useIndex = '';
1375
1376                 $noKeyOptions = array();
1377                 foreach ( $options as $key => $option ) {
1378                         if ( is_numeric( $key ) ) {
1379                                 $noKeyOptions[$option] = true;
1380                         }
1381                 }
1382
1383                 if ( isset( $options['GROUP BY'] ) ) {
1384                         $gb = is_array( $options['GROUP BY'] )
1385                                 ? implode( ',', $options['GROUP BY'] )
1386                                 : $options['GROUP BY'];
1387                         $preLimitTail .= " GROUP BY {$gb}";
1388                 }
1389
1390                 if ( isset( $options['HAVING'] ) ) {
1391                         $preLimitTail .= " HAVING {$options['HAVING']}";
1392                 }
1393
1394                 if ( isset( $options['ORDER BY'] ) ) {
1395                         $ob = is_array( $options['ORDER BY'] )
1396                                 ? implode( ',', $options['ORDER BY'] )
1397                                 : $options['ORDER BY'];
1398                         $preLimitTail .= " ORDER BY {$ob}";
1399                 }
1400
1401                 //if ( isset( $options['LIMIT'] ) ) {
1402                 //      $tailOpts .= $this->limitResult( '', $options['LIMIT'],
1403                 //              isset( $options['OFFSET'] ) ? $options['OFFSET']
1404                 //              : false );
1405                 //}
1406
1407                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1408                         $postLimitTail .= ' FOR UPDATE';
1409                 }
1410                 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1411                         $postLimitTail .= ' LOCK IN SHARE MODE';
1412                 }
1413                 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1414                         $startOpts .= 'DISTINCT';
1415                 }
1416
1417                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1418         }
1419
1420         function setFakeMaster( $enabled = true ) {}
1421
1422         function getDBname() {
1423                 return $this->mDBname;
1424         }
1425
1426         function getServer() {
1427                 return $this->mServer;
1428         }
1429
1430         function buildConcat( $stringList ) {
1431                 return implode( ' || ', $stringList );
1432         }
1433
1434         public function getSearchEngine() {
1435                 return 'SearchPostgres';
1436         }
1437
1438         public function streamStatementEnd( &$sql, &$newLine ) {
1439                 # Allow dollar quoting for function declarations
1440                 if ( substr( $newLine, 0, 4 ) == '$mw$' ) {
1441                         if ( $this->delimiter ) {
1442                                 $this->delimiter = false;
1443                         }
1444                         else {
1445                                 $this->delimiter = ';';
1446                         }
1447                 }
1448                 return parent::streamStatementEnd( $sql, $newLine );
1449         }
1450 } // end DatabasePostgres class