includes/db/DatabasePostgres.php

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