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          * @param string $server
 329          * @param string $user
 330          * @param string $password
 331          * @param string $dbName
 332          * @throws DBConnectionError
 333          * @return DatabaseBase|null
 334          */
 335         function open( $server, $user, $password, $dbName ) {
 336                 # Test for Postgres support, to avoid suppressed fatal error
 337                 if ( !function_exists( 'pg_connect' ) ) {
 338                         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" );
 339                 }
 340
 341                 global $wgDBport;
 342
 343                 if ( !strlen( $user ) ) { # e.g. the class is being loaded
 344                         return;
 345                 }
 346
 347                 $this->mServer = $server;
 348                 $port = $wgDBport;
 349                 $this->mUser = $user;
 350                 $this->mPassword = $password;
 351                 $this->mDBname = $dbName;
 352
 353                 $connectVars = array(
 354                         'dbname' => $dbName,
 355                         'user' => $user,
 356                         'password' => $password
 357                 );
 358                 if ( $server != false && $server != '' ) {
 359                         $connectVars['host'] = $server;
 360                 }
 361                 if ( $port != false && $port != '' ) {
 362                         $connectVars['port'] = $port;
 363                 }
 364                 if ( $this->mFlags & DBO_SSL ) {
 365                         $connectVars['sslmode'] = 1;
 366                 }
 367
 368                 $this->connectString = $this->makeConnectionString( $connectVars, PGSQL_CONNECT_FORCE_NEW );
 369                 $this->close();
 370                 $this->installErrorHandler();
 371                 $this->mConn = pg_connect( $this->connectString );
 372                 $phpError = $this->restoreErrorHandler();
 373
 374                 if ( !$this->mConn ) {
 375                         wfDebug( "DB connection error\n" );
 376                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
 377                         wfDebug( $this->lastError() . "\n" );
 378                         throw new DBConnectionError( $this, str_replace( "\n", ' ', $phpError ) );
 379                 }
 380
 381                 $this->mOpened = true;
 382                 $this->mTransactionState = new PostgresTransactionState( $this->mConn );
 383
 384                 global $wgCommandLineMode;
 385                 # If called from the command-line (e.g. importDump), only show errors
 386                 if ( $wgCommandLineMode ) {
 387                         $this->doQuery( "SET client_min_messages = 'ERROR'" );
 388                 }
 389
 390                 $this->query( "SET client_encoding='UTF8'", __METHOD__ );
 391                 $this->query( "SET datestyle = 'ISO, YMD'", __METHOD__ );
 392                 $this->query( "SET timezone = 'GMT'", __METHOD__ );
 393                 $this->query( "SET standard_conforming_strings = on", __METHOD__ );
 394
 395                 global $wgDBmwschema;
 396                 $this->determineCoreSchema( $wgDBmwschema );
 397
 398                 return $this->mConn;
 399         }
 400
 401         /**
 402          * Postgres doesn't support selectDB in the same way MySQL does. So if the
 403          * DB name doesn't match the open connection, open a new one
 404          * @return
 405          */
 406         function selectDB( $db ) {
 407                 if ( $this->mDBname !== $db ) {
 408                         return (bool)$this->open( $this->mServer, $this->mUser, $this->mPassword, $db );
 409                 } else {
 410                         return true;
 411                 }
 412         }
 413
 414         function makeConnectionString( $vars ) {
 415                 $s = '';
 416                 foreach ( $vars as $name => $value ) {
 417                         $s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
 418                 }
 419                 return $s;
 420         }
 421
 422         /**
 423          * Closes a database connection, if it is open
 424          * Returns success, true if already closed
 425          * @return bool
 426          */
 427         protected function closeConnection() {
 428                 return pg_close( $this->mConn );
 429         }
 430
 431         public function doQuery( $sql ) {
 432                 if ( function_exists( 'mb_convert_encoding' ) ) {
 433                         $sql = mb_convert_encoding( $sql, 'UTF-8' );
 434                 }
 435                 $this->mTransactionState->check();
 436                 if( pg_send_query( $this->mConn, $sql ) === false ) {
 437                         throw new DBUnexpectedError( $this, "Unable to post new query to PostgreSQL\n" );
 438                 }
 439                 $this->mLastResult = pg_get_result( $this->mConn );
 440                 $this->mTransactionState->check();
 441                 $this->mAffectedRows = null;
 442                 if ( pg_result_error( $this->mLastResult ) ) {
 443                         return false;
 444                 }
 445                 return $this->mLastResult;
 446         }
 447
 448         protected function dumpError () {
 449                 $diags = array( PGSQL_DIAG_SEVERITY,
 450                                 PGSQL_DIAG_SQLSTATE,
 451                                 PGSQL_DIAG_MESSAGE_PRIMARY,
 452                                 PGSQL_DIAG_MESSAGE_DETAIL,
 453                                 PGSQL_DIAG_MESSAGE_HINT,
 454                                 PGSQL_DIAG_STATEMENT_POSITION,
 455                                 PGSQL_DIAG_INTERNAL_POSITION,
 456                                 PGSQL_DIAG_INTERNAL_QUERY,
 457                                 PGSQL_DIAG_CONTEXT,
 458                                 PGSQL_DIAG_SOURCE_FILE,
 459                                 PGSQL_DIAG_SOURCE_LINE,
 460                                 PGSQL_DIAG_SOURCE_FUNCTION );
 461                 foreach ( $diags as $d ) {
 462                         wfDebug( sprintf("PgSQL ERROR(%d): %s\n", $d, pg_result_error_field( $this->mLastResult, $d ) ) );
 463                 }
 464         }
 465
 466         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 467                 /* Transaction stays in the ERROR state until rolledback */
 468                 if ( $tempIgnore ) {
 469                         /* Check for constraint violation */
 470                         if ( $errno === '23505' ) {
 471                                 parent::reportQueryError( $error, $errno, $sql, $fname, $tempIgnore );
 472                                 return;
 473                         }
 474                 }
 475                 /* Don't ignore serious errors */
 476                 $this->rollback( __METHOD__ );
 477                 parent::reportQueryError( $error, $errno, $sql, $fname, false );
 478         }
 479
 480
 481         function queryIgnore( $sql, $fname = 'DatabasePostgres::queryIgnore' ) {
 482                 return $this->query( $sql, $fname, true );
 483         }
 484
 485         function freeResult( $res ) {
 486                 if ( $res instanceof ResultWrapper ) {
 487                         $res = $res->result;
 488                 }
 489                 wfSuppressWarnings();
 490                 $ok = pg_free_result( $res );
 491                 wfRestoreWarnings();
 492                 if ( !$ok ) {
 493                         throw new DBUnexpectedError( $this, "Unable to free Postgres result\n" );
 494                 }
 495         }
 496
 497         function fetchObject( $res ) {
 498                 if ( $res instanceof ResultWrapper ) {
 499                         $res = $res->result;
 500                 }
 501                 wfSuppressWarnings();
 502                 $row = pg_fetch_object( $res );
 503                 wfRestoreWarnings();
 504                 # @todo FIXME: HACK HACK HACK HACK debug
 505
 506                 # @todo hashar: not sure if the following test really trigger if the object
 507                 #          fetching failed.
 508                 if( pg_last_error( $this->mConn ) ) {
 509                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 510                 }
 511                 return $row;
 512         }
 513
 514         function fetchRow( $res ) {
 515                 if ( $res instanceof ResultWrapper ) {
 516                         $res = $res->result;
 517                 }
 518                 wfSuppressWarnings();
 519                 $row = pg_fetch_array( $res );
 520                 wfRestoreWarnings();
 521                 if( pg_last_error( $this->mConn ) ) {
 522                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 523                 }
 524                 return $row;
 525         }
 526
 527         function numRows( $res ) {
 528                 if ( $res instanceof ResultWrapper ) {
 529                         $res = $res->result;
 530                 }
 531                 wfSuppressWarnings();
 532                 $n = pg_num_rows( $res );
 533                 wfRestoreWarnings();
 534                 if( pg_last_error( $this->mConn ) ) {
 535                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 536                 }
 537                 return $n;
 538         }
 539
 540         function numFields( $res ) {
 541                 if ( $res instanceof ResultWrapper ) {
 542                         $res = $res->result;
 543                 }
 544                 return pg_num_fields( $res );
 545         }
 546
 547         function fieldName( $res, $n ) {
 548                 if ( $res instanceof ResultWrapper ) {
 549                         $res = $res->result;
 550                 }
 551                 return pg_field_name( $res, $n );
 552         }
 553
 554         /**
 555          * This must be called after nextSequenceVal
 556          * @return null
 557          */
 558         function insertId() {
 559                 return $this->mInsertId;
 560         }
 561
 562         function dataSeek( $res, $row ) {
 563                 if ( $res instanceof ResultWrapper ) {
 564                         $res = $res->result;
 565                 }
 566                 return pg_result_seek( $res, $row );
 567         }
 568
 569         function lastError() {
 570                 if ( $this->mConn ) {
 571                         if ( $this->mLastResult ) {
 572                                 return pg_result_error( $this->mLastResult );
 573                         } else {
 574                                 return pg_last_error();
 575                         }
 576                 } else {
 577                         return 'No database connection';
 578                 }
 579         }
 580         function lastErrno() {
 581                 if ( $this->mLastResult ) {
 582                         return pg_result_error_field( $this->mLastResult, PGSQL_DIAG_SQLSTATE );
 583                 } else {
 584                         return false;
 585                 }
 586         }
 587
 588         function affectedRows() {
 589                 if ( !is_null( $this->mAffectedRows ) ) {
 590                         // Forced result for simulated queries
 591                         return $this->mAffectedRows;
 592                 }
 593                 if( empty( $this->mLastResult ) ) {
 594                         return 0;
 595                 }
 596                 return pg_affected_rows( $this->mLastResult );
 597         }
 598
 599         /**
 600          * Estimate rows in dataset
 601          * Returns estimated count, based on EXPLAIN output
 602          * This is not necessarily an accurate estimate, so use sparingly
 603          * Returns -1 if count cannot be found
 604          * Takes same arguments as Database::select()
 605          * @return int
 606          */
 607         function estimateRowCount( $table, $vars = '*', $conds='', $fname = 'DatabasePostgres::estimateRowCount', $options = array() ) {
 608                 $options['EXPLAIN'] = true;
 609                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 610                 $rows = -1;
 611                 if ( $res ) {
 612                         $row = $this->fetchRow( $res );
 613                         $count = array();
 614                         if( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
 615                                 $rows = $count[1];
 616                         }
 617                 }
 618                 return $rows;
 619         }
 620
 621         /**
 622          * Returns information about an index
 623          * If errors are explicitly ignored, returns NULL on failure
 624          * @return bool|null
 625          */
 626         function indexInfo( $table, $index, $fname = 'DatabasePostgres::indexInfo' ) {
 627                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 628                 $res = $this->query( $sql, $fname );
 629                 if ( !$res ) {
 630                         return null;
 631                 }
 632                 foreach ( $res as $row ) {
 633                         if ( $row->indexname == $this->indexName( $index ) ) {
 634                                 return $row;
 635                         }
 636                 }
 637                 return false;
 638         }
 639
 640         /**
 641          * Returns is of attributes used in index
 642          *
 643          * @since 1.19
 644          * @return Array
 645          */
 646         function indexAttributes ( $index, $schema = false ) {
 647                 if ( $schema === false )
 648                         $schema = $this->getCoreSchema();
 649                 /*
 650                  * A subquery would be not needed if we didn't care about the order
 651                  * of attributes, but we do
 652                  */
 653                 $sql = <<<__INDEXATTR__
 654
 655                         SELECT opcname,
 656                                 attname,
 657                                 i.indoption[s.g] as option,
 658                                 pg_am.amname
 659                         FROM
 660                                 (SELECT generate_series(array_lower(isub.indkey,1), array_upper(isub.indkey,1)) AS g
 661                                         FROM
 662                                                 pg_index isub
 663                                         JOIN pg_class cis
 664                                                 ON cis.oid=isub.indexrelid
 665                                         JOIN pg_namespace ns
 666                                                 ON cis.relnamespace = ns.oid
 667                                         WHERE cis.relname='$index' AND ns.nspname='$schema') AS s,
 668                                 pg_attribute,
 669                                 pg_opclass opcls,
 670                                 pg_am,
 671                                 pg_class ci
 672                                 JOIN pg_index i
 673                                         ON ci.oid=i.indexrelid
 674                                 JOIN pg_class ct
 675                                         ON ct.oid = i.indrelid
 676                                 JOIN pg_namespace n
 677                                         ON ci.relnamespace = n.oid
 678                                 WHERE
 679                                         ci.relname='$index' AND n.nspname='$schema'
 680                                         AND     attrelid = ct.oid
 681                                         AND     i.indkey[s.g] = attnum
 682                                         AND     i.indclass[s.g] = opcls.oid
 683                                         AND     pg_am.oid = opcls.opcmethod
 684 __INDEXATTR__;
 685                 $res = $this->query($sql, __METHOD__);
 686                 $a = array();
 687                 if ( $res ) {
 688                         foreach ( $res as $row ) {
 689                                 $a[] = array(
 690                                         $row->attname,
 691                                         $row->opcname,
 692                                         $row->amname,
 693                                         $row->option);
 694                         }
 695                 } else {
 696                         return null;
 697                 }
 698                 return $a;
 699         }
 700
 701
 702         function indexUnique( $table, $index, $fname = 'DatabasePostgres::indexUnique' ) {
 703                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 704                         " AND indexdef LIKE 'CREATE UNIQUE%(" .
 705                         $this->strencode( $this->indexName( $index ) ) .
 706                         ")'";
 707                 $res = $this->query( $sql, $fname );
 708                 if ( !$res ) {
 709                         return null;
 710                 }
 711                 foreach ( $res as $row ) {
 712                         return true;
 713                 }
 714                 return false;
 715         }
 716
 717         /**
 718          * INSERT wrapper, inserts an array into a table
 719          *
 720          * $args may be a single associative array, or an array of these with numeric keys,
 721          * for multi-row insert (Postgres version 8.2 and above only).
 722          *
 723          * @param $table   String: Name of the table to insert to.
 724          * @param $args    Array: Items to insert into the table.
 725          * @param $fname   String: Name of the function, for profiling
 726          * @param $options String or Array. Valid options: IGNORE
 727          *
 728          * @return bool Success of insert operation. IGNORE always returns true.
 729          */
 730         function insert( $table, $args, $fname = 'DatabasePostgres::insert', $options = array() ) {
 731                 if ( !count( $args ) ) {
 732                         return true;
 733                 }
 734
 735                 $table = $this->tableName( $table );
 736                 if (! isset( $this->numeric_version ) ) {
 737                         $this->getServerVersion();
 738                 }
 739
 740                 if ( !is_array( $options ) ) {
 741                         $options = array( $options );
 742                 }
 743
 744                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 745                         $multi = true;
 746                         $keys = array_keys( $args[0] );
 747                 } else {
 748                         $multi = false;
 749                         $keys = array_keys( $args );
 750                 }
 751
 752                 // If IGNORE is set, we use savepoints to emulate mysql's behavior
 753                 $savepoint = null;
 754                 if ( in_array( 'IGNORE', $options ) ) {
 755                         $savepoint = new SavepointPostgres( $this, 'mw' );
 756                         $olde = error_reporting( 0 );
 757                         // For future use, we may want to track the number of actual inserts
 758                         // Right now, insert (all writes) simply return true/false
 759                         $numrowsinserted = 0;
 760                 }
 761
 762                 $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 763
 764                 if ( $multi ) {
 765                         if ( $this->numeric_version >= 8.2 && !$savepoint ) {
 766                                 $first = true;
 767                                 foreach ( $args as $row ) {
 768                                         if ( $first ) {
 769                                                 $first = false;
 770                                         } else {
 771                                                 $sql .= ',';
 772                                         }
 773                                         $sql .= '(' . $this->makeList( $row ) . ')';
 774                                 }
 775                                 $res = (bool)$this->query( $sql, $fname, $savepoint );
 776                         } else {
 777                                 $res = true;
 778                                 $origsql = $sql;
 779                                 foreach ( $args as $row ) {
 780                                         $tempsql = $origsql;
 781                                         $tempsql .= '(' . $this->makeList( $row ) . ')';
 782
 783                                         if ( $savepoint ) {
 784                                                 $savepoint->savepoint();
 785                                         }
 786
 787                                         $tempres = (bool)$this->query( $tempsql, $fname, $savepoint );
 788
 789                                         if ( $savepoint ) {
 790                                                 $bar = pg_last_error();
 791                                                 if ( $bar != false ) {
 792                                                         $savepoint->rollback();
 793                                                 } else {
 794                                                         $savepoint->release();
 795                                                         $numrowsinserted++;
 796                                                 }
 797                                         }
 798
 799                                         // If any of them fail, we fail overall for this function call
 800                                         // Note that this will be ignored if IGNORE is set
 801                                         if ( !$tempres ) {
 802                                                 $res = false;
 803                                         }
 804                                 }
 805                         }
 806                 } else {
 807                         // Not multi, just a lone insert
 808                         if ( $savepoint ) {
 809                                 $savepoint->savepoint();
 810                         }
 811
 812                         $sql .= '(' . $this->makeList( $args ) . ')';
 813                         $res = (bool)$this->query( $sql, $fname, $savepoint );
 814                         if ( $savepoint ) {
 815                                 $bar = pg_last_error();
 816                                 if ( $bar != false ) {
 817                                         $savepoint->rollback();
 818                                 } else {
 819                                         $savepoint->release();
 820                                         $numrowsinserted++;
 821                                 }
 822                         }
 823                 }
 824                 if ( $savepoint ) {
 825                         $olde = error_reporting( $olde );
 826                         $savepoint->commit();
 827
 828                         // Set the affected row count for the whole operation
 829                         $this->mAffectedRows = $numrowsinserted;
 830
 831                         // IGNORE always returns true
 832                         return true;
 833                 }
 834
 835                 return $res;
 836         }
 837
 838         /**
 839          * INSERT SELECT wrapper
 840          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
 841          * Source items may be literals rather then field names, but strings should be quoted with Database::addQuotes()
 842          * $conds may be "*" to copy the whole table
 843          * srcTable may be an array of tables.
 844          * @todo FIXME: Implement this a little better (seperate select/insert)?
 845          * @return bool
 846          */
 847         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'DatabasePostgres::insertSelect',
 848                 $insertOptions = array(), $selectOptions = array() )
 849         {
 850                 $destTable = $this->tableName( $destTable );
 851
 852                 if( !is_array( $insertOptions ) ) {
 853                         $insertOptions = array( $insertOptions );
 854                 }
 855
 856                 /*
 857                  * If IGNORE is set, we use savepoints to emulate mysql's behavior
 858                  * Ignore LOW PRIORITY option, since it is MySQL-specific
 859                  */
 860                 $savepoint = null;
 861                 if ( in_array( 'IGNORE', $insertOptions ) ) {
 862                         $savepoint = new SavepointPostgres( $this, 'mw' );
 863                         $olde = error_reporting( 0 );
 864                         $numrowsinserted = 0;
 865                         $savepoint->savepoint();
 866                 }
 867
 868                 if( !is_array( $selectOptions ) ) {
 869                         $selectOptions = array( $selectOptions );
 870                 }
 871                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
 872                 if( is_array( $srcTable ) ) {
 873                         $srcTable = implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
 874                 } else {
 875                         $srcTable = $this->tableName( $srcTable );
 876                 }
 877
 878                 $sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
 879                                 " SELECT $startOpts " . implode( ',', $varMap ) .
 880                                 " FROM $srcTable $useIndex";
 881
 882                 if ( $conds != '*' ) {
 883                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
 884                 }
 885
 886                 $sql .= " $tailOpts";
 887
 888                 $res = (bool)$this->query( $sql, $fname, $savepoint );
 889                 if( $savepoint ) {
 890                         $bar = pg_last_error();
 891                         if( $bar != false ) {
 892                                 $savepoint->rollback();
 893                         } else {
 894                                 $savepoint->release();
 895                                 $numrowsinserted++;
 896                         }
 897                         $olde = error_reporting( $olde );
 898                         $savepoint->commit();
 899
 900                         // Set the affected row count for the whole operation
 901                         $this->mAffectedRows = $numrowsinserted;
 902
 903                         // IGNORE always returns true
 904                         return true;
 905                 }
 906
 907                 return $res;
 908         }
 909
 910         function tableName( $name, $format = 'quoted' ) {
 911                 # Replace reserved words with better ones
 912                 switch( $name ) {
 913                         case 'user':
 914                                 return $this->realTableName( 'mwuser', $format );
 915                         case 'text':
 916                                 return $this->realTableName( 'pagecontent', $format );
 917                         default:
 918                                 return $this->realTableName( $name, $format );
 919                 }
 920         }
 921
 922         /* Don't cheat on installer */
 923         function realTableName( $name, $format = 'quoted' ) {
 924                 return parent::tableName( $name, $format );
 925         }
 926
 927         /**
 928          * Return the next in a sequence, save the value for retrieval via insertId()
 929          * @return null
 930          */
 931         function nextSequenceValue( $seqName ) {
 932                 $safeseq = str_replace( "'", "''", $seqName );
 933                 $res = $this->query( "SELECT nextval('$safeseq')" );
 934                 $row = $this->fetchRow( $res );
 935                 $this->mInsertId = $row[0];
 936                 return $this->mInsertId;
 937         }
 938
 939         /**
 940          * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
 941          * @return
 942          */
 943         function currentSequenceValue( $seqName ) {
 944                 $safeseq = str_replace( "'", "''", $seqName );
 945                 $res = $this->query( "SELECT currval('$safeseq')" );
 946                 $row = $this->fetchRow( $res );
 947                 $currval = $row[0];
 948                 return $currval;
 949         }
 950
 951         # Returns the size of a text field, or -1 for "unlimited"
 952         function textFieldSize( $table, $field ) {
 953                 $table = $this->tableName( $table );
 954                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
 955                         FROM pg_class c, pg_attribute a, pg_type t
 956                         WHERE relname='$table' AND a.attrelid=c.oid AND
 957                                 a.atttypid=t.oid and a.attname='$field'";
 958                 $res =$this->query( $sql );
 959                 $row = $this->fetchObject( $res );
 960                 if ( $row->ftype == 'varchar' ) {
 961                         $size = $row->size - 4;
 962                 } else {
 963                         $size = $row->size;
 964                 }
 965                 return $size;
 966         }
 967
 968         function limitResult( $sql, $limit, $offset = false ) {
 969                 return "$sql LIMIT $limit " . ( is_numeric( $offset ) ? " OFFSET {$offset} " : '' );
 970         }
 971
 972         function wasDeadlock() {
 973                 return $this->lastErrno() == '40P01';
 974         }
 975
 976         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabasePostgres::duplicateTableStructure' ) {
 977                 $newName = $this->addIdentifierQuotes( $newName );
 978                 $oldName = $this->addIdentifierQuotes( $oldName );
 979                 return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName (LIKE $oldName INCLUDING DEFAULTS)", $fname );
 980         }
 981
 982         function listTables( $prefix = null, $fname = 'DatabasePostgres::listTables' ) {
 983                 $eschema = $this->addQuotes( $this->getCoreSchema() );
 984                 $result = $this->query( "SELECT tablename FROM pg_tables WHERE schemaname = $eschema", $fname );
 985                 $endArray = array();
 986
 987                 foreach( $result as $table ) {
 988                         $vars = get_object_vars($table);
 989                         $table = array_pop( $vars );
 990                         if( !$prefix || strpos( $table, $prefix ) === 0 ) {
 991                                 $endArray[] = $table;
 992                         }
 993                 }
 994
 995                 return $endArray;
 996         }
 997
 998         function timestamp( $ts = 0 ) {
 999                 return wfTimestamp( TS_POSTGRES, $ts );
1000         }
1001
1002         /*
1003          * Posted by cc[plus]php[at]c2se[dot]com on 25-Mar-2009 09:12
1004          * to http://www.php.net/manual/en/ref.pgsql.php
1005          *
1006          * Parsing a postgres array can be a tricky problem, he's my
1007          * take on this, it handles multi-dimensional arrays plus
1008          * escaping using a nasty regexp to determine the limits of each
1009          * data-item.
1010          *
1011          * This should really be handled by PHP PostgreSQL module
1012          *
1013          * @since 1.19
1014          * @param $text   string: postgreql array returned in a text form like {a,b}
1015          * @param $output string
1016          * @param $limit  int
1017          * @param $offset int
1018          * @return string
1019          */
1020         function pg_array_parse( $text, &$output, $limit = false, $offset = 1 ) {
1021                 if( false === $limit ) {
1022                         $limit = strlen( $text )-1;
1023                         $output = array();
1024                 }
1025                 if( '{}' == $text ) {
1026                         return $output;
1027                 }
1028                 do {
1029                         if ( '{' != $text{$offset} ) {
1030                                 preg_match( "/(\\{?\"([^\"\\\\]|\\\\.)*\"|[^,{}]+)+([,}]+)/",
1031                                         $text, $match, 0, $offset );
1032                                 $offset += strlen( $match[0] );
1033                                 $output[] = ( '"' != $match[1]{0}
1034                                                 ? $match[1]
1035                                                 : stripcslashes( substr( $match[1], 1, -1 ) ) );
1036                                 if ( '},' == $match[3] ) {
1037                                         return $output;
1038                                 }
1039                         } else {
1040                                 $offset = $this->pg_array_parse( $text, $output, $limit, $offset+1 );
1041                         }
1042                 } while ( $limit > $offset );
1043                 return $output;
1044         }
1045
1046         /**
1047          * Return aggregated value function call
1048          */
1049         public function aggregateValue( $valuedata, $valuename = 'value' ) {
1050                 return $valuedata;
1051         }
1052
1053         /**
1054          * @return string wikitext of a link to the server software's web site
1055          */
1056         public static function getSoftwareLink() {
1057                 return '[http://www.postgresql.org/ PostgreSQL]';
1058         }
1059
1060
1061         /**
1062          * Return current schema (executes SELECT current_schema())
1063          * Needs transaction
1064          *
1065          * @since 1.19
1066          * @return string return default schema for the current session
1067          */
1068         function getCurrentSchema() {
1069                 $res = $this->query( "SELECT current_schema()", __METHOD__);
1070                 $row = $this->fetchRow( $res );
1071                 return $row[0];
1072         }
1073
1074         /**
1075          * Return list of schemas which are accessible without schema name
1076          * This is list does not contain magic keywords like "$user"
1077          * Needs transaction
1078          *
1079          * @seealso getSearchPath()
1080          * @seealso setSearchPath()
1081          * @since 1.19
1082          * @return array list of actual schemas for the current sesson
1083          */
1084         function getSchemas() {
1085                 $res = $this->query( "SELECT current_schemas(false)", __METHOD__);
1086                 $row = $this->fetchRow( $res );
1087                 $schemas = array();
1088                 /* PHP pgsql support does not support array type, "{a,b}" string is returned */
1089                 return $this->pg_array_parse($row[0], $schemas);
1090         }
1091
1092         /**
1093          * Return search patch for schemas
1094          * This is different from getSchemas() since it contain magic keywords
1095          * (like "$user").
1096          * Needs transaction
1097          *
1098          * @since 1.19
1099          * @return array how to search for table names schemas for the current user
1100          */
1101         function getSearchPath() {
1102                 $res = $this->query( "SHOW search_path", __METHOD__);
1103                 $row = $this->fetchRow( $res );
1104                 /* PostgreSQL returns SHOW values as strings */
1105                 return explode(",", $row[0]);
1106         }
1107
1108         /**
1109          * Update search_path, values should already be sanitized
1110          * Values may contain magic keywords like "$user"
1111          * @since 1.19
1112          *
1113          * @param $search_path array list of schemas to be searched by default
1114          */
1115         function setSearchPath( $search_path ) {
1116                 $this->query( "SET search_path = " . implode(", ", $search_path) );
1117         }
1118
1119         /**
1120          * Determine default schema for MediaWiki core
1121          * Adjust this session schema search path if desired schema exists
1122          * and is not alread there.
1123          *
1124          * We need to have name of the core schema stored to be able
1125          * to query database metadata.
1126          *
1127          * This will be also called by the installer after the schema is created
1128          *
1129          * @since 1.19
1130          * @param $desired_schema string
1131          */
1132         function determineCoreSchema( $desired_schema ) {
1133                 $this->begin( __METHOD__ );
1134                 if ( $this->schemaExists( $desired_schema ) ) {
1135                         if ( in_array( $desired_schema, $this->getSchemas() ) ) {
1136                                 $this->mCoreSchema = $desired_schema;
1137                                 wfDebug("Schema \"" . $desired_schema . "\" already in the search path\n");
1138                         } else {
1139                                 /**
1140                                  * Prepend our schema (e.g. 'mediawiki') in front
1141                                  * of the search path
1142                                  * Fixes bug 15816
1143                                  */
1144                                 $search_path = $this->getSearchPath();
1145                                 array_unshift( $search_path,
1146                                         $this->addIdentifierQuotes( $desired_schema ));
1147                                 $this->setSearchPath( $search_path );
1148                                 $this->mCoreSchema = $desired_schema;
1149                                 wfDebug("Schema \"" . $desired_schema . "\" added to the search path\n");
1150                         }
1151                 } else {
1152                         $this->mCoreSchema = $this->getCurrentSchema();
1153                         wfDebug("Schema \"" . $desired_schema . "\" not found, using current \"". $this->mCoreSchema ."\"\n");
1154                 }
1155                 /* Commit SET otherwise it will be rollbacked on error or IGNORE SELECT */
1156                 $this->commit( __METHOD__ );
1157         }
1158
1159         /**
1160          * Return schema name fore core MediaWiki tables
1161          *
1162          * @since 1.19
1163          * @return string core schema name
1164          */
1165         function getCoreSchema() {
1166                 return $this->mCoreSchema;
1167         }
1168
1169         /**
1170          * @return string Version information from the database
1171          */
1172         function getServerVersion() {
1173                 if ( !isset( $this->numeric_version ) ) {
1174                         $versionInfo = pg_version( $this->mConn );
1175                         if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
1176                                 // Old client, abort install
1177                                 $this->numeric_version = '7.3 or earlier';
1178                         } elseif ( isset( $versionInfo['server'] ) ) {
1179                                 // Normal client
1180                                 $this->numeric_version = $versionInfo['server'];
1181                         } else {
1182                                 // Bug 16937: broken pgsql extension from PHP<5.3
1183                                 $this->numeric_version = pg_parameter_status( $this->mConn, 'server_version' );
1184                         }
1185                 }
1186                 return $this->numeric_version;
1187         }
1188
1189         /**
1190          * Query whether a given relation exists (in the given schema, or the
1191          * default mw one if not given)
1192          * @return bool
1193          */
1194         function relationExists( $table, $types, $schema = false ) {
1195                 if ( !is_array( $types ) ) {
1196                         $types = array( $types );
1197                 }
1198                 if ( !$schema ) {
1199                         $schema = $this->getCoreSchema();
1200                 }
1201                 $table = $this->realTableName( $table, 'raw' );
1202                 $etable = $this->addQuotes( $table );
1203                 $eschema = $this->addQuotes( $schema );
1204                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
1205                         . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
1206                         . "AND c.relkind IN ('" . implode( "','", $types ) . "')";
1207                 $res = $this->query( $SQL );
1208                 $count = $res ? $res->numRows() : 0;
1209                 return (bool)$count;
1210         }
1211
1212         /**
1213          * For backward compatibility, this function checks both tables and
1214          * views.
1215          * @return bool
1216          */
1217         function tableExists( $table, $fname = __METHOD__, $schema = false ) {
1218                 return $this->relationExists( $table, array( 'r', 'v' ), $schema );
1219         }
1220
1221         function sequenceExists( $sequence, $schema = false ) {
1222                 return $this->relationExists( $sequence, 'S', $schema );
1223         }
1224
1225         function triggerExists( $table, $trigger ) {
1226                 $q = <<<SQL
1227         SELECT 1 FROM pg_class, pg_namespace, pg_trigger
1228                 WHERE relnamespace=pg_namespace.oid AND relkind='r'
1229                           AND tgrelid=pg_class.oid
1230                           AND nspname=%s AND relname=%s AND tgname=%s
1231 SQL;
1232                 $res = $this->query(
1233                         sprintf(
1234                                 $q,
1235                                 $this->addQuotes( $this->getCoreSchema() ),
1236                                 $this->addQuotes( $table ),
1237                                 $this->addQuotes( $trigger )
1238                         )
1239                 );
1240                 if ( !$res ) {
1241                         return null;
1242                 }
1243                 $rows = $res->numRows();
1244                 return $rows;
1245         }
1246
1247         function ruleExists( $table, $rule ) {
1248                 $exists = $this->selectField( 'pg_rules', 'rulename',
1249                         array(
1250                                 'rulename' => $rule,
1251                                 'tablename' => $table,
1252                                 'schemaname' => $this->getCoreSchema()
1253                         )
1254                 );
1255                 return $exists === $rule;
1256         }
1257
1258         function constraintExists( $table, $constraint ) {
1259                 $SQL = sprintf( "SELECT 1 FROM information_schema.table_constraints ".
1260                            "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
1261                         $this->addQuotes( $this->getCoreSchema() ),
1262                         $this->addQuotes( $table ),
1263                         $this->addQuotes( $constraint )
1264                 );
1265                 $res = $this->query( $SQL );
1266                 if ( !$res ) {
1267                         return null;
1268                 }
1269                 $rows = $res->numRows();
1270                 return $rows;
1271         }
1272
1273         /**
1274          * Query whether a given schema exists. Returns true if it does, false if it doesn't.
1275          * @return bool
1276          */
1277         function schemaExists( $schema ) {
1278                 $exists = $this->selectField( '"pg_catalog"."pg_namespace"', 1,
1279                         array( 'nspname' => $schema ), __METHOD__ );
1280                 return (bool)$exists;
1281         }
1282
1283         /**
1284          * Returns true if a given role (i.e. user) exists, false otherwise.
1285          * @return bool
1286          */
1287         function roleExists( $roleName ) {
1288                 $exists = $this->selectField( '"pg_catalog"."pg_roles"', 1,
1289                         array( 'rolname' => $roleName ), __METHOD__ );
1290                 return (bool)$exists;
1291         }
1292
1293         function fieldInfo( $table, $field ) {
1294                 return PostgresField::fromText( $this, $table, $field );
1295         }
1296
1297         /**
1298          * pg_field_type() wrapper
1299          * @return string
1300          */
1301         function fieldType( $res, $index ) {
1302                 if ( $res instanceof ResultWrapper ) {
1303                         $res = $res->result;
1304                 }
1305                 return pg_field_type( $res, $index );
1306         }
1307
1308         /**
1309          * @param $b
1310          * @return Blob
1311          */
1312         function encodeBlob( $b ) {
1313                 return new Blob( pg_escape_bytea( $this->mConn, $b ) );
1314         }
1315
1316         function decodeBlob( $b ) {
1317                 if ( $b instanceof Blob ) {
1318                         $b = $b->fetch();
1319                 }
1320                 return pg_unescape_bytea( $b );
1321         }
1322
1323         function strencode( $s ) { # Should not be called by us
1324                 return pg_escape_string( $this->mConn, $s );
1325         }
1326
1327         /**
1328          * @param $s null|bool|Blob
1329          * @return int|string
1330          */
1331         function addQuotes( $s ) {
1332                 if ( is_null( $s ) ) {
1333                         return 'NULL';
1334                 } elseif ( is_bool( $s ) ) {
1335                         return intval( $s );
1336                 } elseif ( $s instanceof Blob ) {
1337                         return "'" . $s->fetch( $s ) . "'";
1338                 }
1339                 return "'" . pg_escape_string( $this->mConn, $s ) . "'";
1340         }
1341
1342         /**
1343          * Postgres specific version of replaceVars.
1344          * Calls the parent version in Database.php
1345          *
1346          * @private
1347          *
1348          * @param $ins String: SQL string, read from a stream (usually tables.sql)
1349          *
1350          * @return string SQL string
1351          */
1352         protected function replaceVars( $ins ) {
1353                 $ins = parent::replaceVars( $ins );
1354
1355                 if ( $this->numeric_version >= 8.3 ) {
1356                         // Thanks for not providing backwards-compatibility, 8.3
1357                         $ins = preg_replace( "/to_tsvector\s*\(\s*'default'\s*,/", 'to_tsvector(', $ins );
1358                 }
1359
1360                 if ( $this->numeric_version <= 8.1 ) { // Our minimum version
1361                         $ins = str_replace( 'USING gin', 'USING gist', $ins );
1362                 }
1363
1364                 return $ins;
1365         }
1366
1367         /**
1368          * Various select options
1369          *
1370          * @private
1371          *
1372          * @param $options Array: an associative array of options to be turned into
1373          *              an SQL query, valid keys are listed in the function.
1374          * @return array
1375          */
1376         function makeSelectOptions( $options ) {
1377                 $preLimitTail = $postLimitTail = '';
1378                 $startOpts = $useIndex = '';
1379
1380                 $noKeyOptions = array();
1381                 foreach ( $options as $key => $option ) {
1382                         if ( is_numeric( $key ) ) {
1383                                 $noKeyOptions[$option] = true;
1384                         }
1385                 }
1386
1387                 if ( isset( $options['GROUP BY'] ) ) {
1388                         $gb = is_array( $options['GROUP BY'] )
1389                                 ? implode( ',', $options['GROUP BY'] )
1390                                 : $options['GROUP BY'];
1391                         $preLimitTail .= " GROUP BY {$gb}";
1392                 }
1393
1394                 if ( isset( $options['HAVING'] ) ) {
1395                         $preLimitTail .= " HAVING {$options['HAVING']}";
1396                 }
1397
1398                 if ( isset( $options['ORDER BY'] ) ) {
1399                         $ob = is_array( $options['ORDER BY'] )
1400                                 ? implode( ',', $options['ORDER BY'] )
1401                                 : $options['ORDER BY'];
1402                         $preLimitTail .= " ORDER BY {$ob}";
1403                 }
1404
1405                 //if ( isset( $options['LIMIT'] ) ) {
1406                 //      $tailOpts .= $this->limitResult( '', $options['LIMIT'],
1407                 //              isset( $options['OFFSET'] ) ? $options['OFFSET']
1408                 //              : false );
1409                 //}
1410
1411                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1412                         $postLimitTail .= ' FOR UPDATE';
1413                 }
1414                 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1415                         $startOpts .= 'DISTINCT';
1416                 }
1417
1418                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1419         }
1420
1421         function setFakeMaster( $enabled = true ) {}
1422
1423         function getDBname() {
1424                 return $this->mDBname;
1425         }
1426
1427         function getServer() {
1428                 return $this->mServer;
1429         }
1430
1431         function buildConcat( $stringList ) {
1432                 return implode( ' || ', $stringList );
1433         }
1434
1435         public function getSearchEngine() {
1436                 return 'SearchPostgres';
1437         }
1438
1439         public function streamStatementEnd( &$sql, &$newLine ) {
1440                 # Allow dollar quoting for function declarations
1441                 if ( substr( $newLine, 0, 4 ) == '$mw$' ) {
1442                         if ( $this->delimiter ) {
1443                                 $this->delimiter = false;
1444                         }
1445                         else {
1446                                 $this->delimiter = ';';
1447                         }
1448                 }
1449                 return parent::streamStatementEnd( $sql, $newLine );
1450         }
1451 } // end DatabasePostgres class