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 {
  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 nullable() {
  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 __construct( $server = false, $user = false, $password = false, $dbName = false,
 104                 $flags = 0 )
 105         {
 106                 $this->mFlags = $flags;
 107                 $this->open( $server, $user, $password, $dbName );
 108         }
 109
 110         function getType() {
 111                 return 'postgres';
 112         }
 113
 114         function cascadingDeletes() {
 115                 return true;
 116         }
 117         function cleanupTriggers() {
 118                 return true;
 119         }
 120         function strictIPs() {
 121                 return true;
 122         }
 123         function realTimestamps() {
 124                 return true;
 125         }
 126         function implicitGroupby() {
 127                 return false;
 128         }
 129         function implicitOrderby() {
 130                 return false;
 131         }
 132         function searchableIPs() {
 133                 return true;
 134         }
 135         function functionalIndexes() {
 136                 return true;
 137         }
 138
 139         function hasConstraint( $name ) {
 140                 global $wgDBmwschema;
 141                 $SQL = "SELECT 1 FROM pg_catalog.pg_constraint c, pg_catalog.pg_namespace n WHERE c.connamespace = n.oid AND conname = '" .
 142                                 pg_escape_string( $this->mConn, $name ) . "' AND n.nspname = '" . pg_escape_string( $this->mConn, $wgDBmwschema ) ."'";
 143                 $res = $this->doQuery( $SQL );
 144                 return $this->numRows( $res );
 145         }
 146
 147         static function newFromParams( $server, $user, $password, $dbName, $flags = 0 ) {
 148                 return new DatabasePostgres( $server, $user, $password, $dbName, $flags );
 149         }
 150
 151         /**
 152          * Usually aborts on failure
 153          */
 154         function open( $server, $user, $password, $dbName ) {
 155                 # Test for Postgres support, to avoid suppressed fatal error
 156                 if ( !function_exists( 'pg_connect' ) ) {
 157                         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" );
 158                 }
 159
 160                 global $wgDBport;
 161
 162                 if ( !strlen( $user ) ) { # e.g. the class is being loaded
 163                         return;
 164                 }
 165                 $this->close();
 166                 $this->mServer = $server;
 167                 $this->mPort = $port = $wgDBport;
 168                 $this->mUser = $user;
 169                 $this->mPassword = $password;
 170                 $this->mDBname = $dbName;
 171
 172                 $connectVars = array(
 173                         'dbname' => $dbName,
 174                         'user' => $user,
 175                         'password' => $password
 176                 );
 177                 if ( $server != false && $server != '' ) {
 178                         $connectVars['host'] = $server;
 179                 }
 180                 if ( $port != false && $port != '' ) {
 181                         $connectVars['port'] = $port;
 182                 }
 183                 $connectString = $this->makeConnectionString( $connectVars, PGSQL_CONNECT_FORCE_NEW );
 184
 185                 $this->installErrorHandler();
 186                 $this->mConn = pg_connect( $connectString );
 187                 $phpError = $this->restoreErrorHandler();
 188
 189                 if ( !$this->mConn ) {
 190                         wfDebug( "DB connection error\n" );
 191                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
 192                         wfDebug( $this->lastError() . "\n" );
 193                         throw new DBConnectionError( $this, $phpError );
 194                 }
 195
 196                 $this->mOpened = true;
 197
 198                 global $wgCommandLineMode;
 199                 # If called from the command-line (e.g. importDump), only show errors
 200                 if ( $wgCommandLineMode ) {
 201                         $this->doQuery( "SET client_min_messages = 'ERROR'" );
 202                 }
 203
 204                 $this->doQuery( "SET client_encoding='UTF8'" );
 205
 206                 global $wgDBmwschema, $wgDBts2schema;
 207                 if ( isset( $wgDBmwschema ) && isset( $wgDBts2schema )
 208                         && $wgDBmwschema !== 'mediawiki'
 209                         && preg_match( '/^\w+$/', $wgDBmwschema )
 210                         && preg_match( '/^\w+$/', $wgDBts2schema )
 211                 ) {
 212                         $safeschema = $this->quote_ident( $wgDBmwschema );
 213                         $this->doQuery( "SET search_path = $safeschema, $wgDBts2schema, public" );
 214                 }
 215
 216                 return $this->mConn;
 217         }
 218
 219         function makeConnectionString( $vars ) {
 220                 $s = '';
 221                 foreach ( $vars as $name => $value ) {
 222                         $s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
 223                 }
 224                 return $s;
 225         }
 226
 227
 228         function initial_setup( $superuser, $password, $dbName ) {
 229                 // If this is the initial connection, setup the schema stuff and possibly create the user
 230                 global $wgDBname, $wgDBuser, $wgDBpassword, $wgDBmwschema, $wgDBts2schema;
 231
 232                 print '<li>Checking the version of Postgres...';
 233                 $version = $this->getServerVersion();
 234                 $PGMINVER = '8.1';
 235                 if ( $version < $PGMINVER ) {
 236                         print "<b>FAILED</b>. Required version is $PGMINVER. You have " . htmlspecialchars( $version ) . "</li>\n";
 237                         dieout( '' );
 238                 }
 239                 print 'version ' . htmlspecialchars( $this->numeric_version ) . " is OK.</li>\n";
 240
 241                 $safeuser = $this->quote_ident( $wgDBuser );
 242                 // Are we connecting as a superuser for the first time?
 243                 if ( $superuser ) {
 244                         // Are we really a superuser? Check out our rights
 245                         $SQL = "SELECT
 246                       CASE WHEN usesuper IS TRUE THEN
 247                       CASE WHEN usecreatedb IS TRUE THEN 3 ELSE 1 END
 248                       ELSE CASE WHEN usecreatedb IS TRUE THEN 2 ELSE 0 END
 249                     END AS rights
 250                     FROM pg_catalog.pg_user WHERE usename = " . $this->addQuotes( $superuser );
 251                         $rows = $this->numRows( $res = $this->doQuery( $SQL ) );
 252                         if ( !$rows ) {
 253                                 print '<li>ERROR: Could not read permissions for user "' . htmlspecialchars( $superuser ) . "\"</li>\n";
 254                                 dieout( '' );
 255                         }
 256                         $perms = pg_fetch_result( $res, 0, 0 );
 257
 258                         $SQL = "SELECT 1 FROM pg_catalog.pg_user WHERE usename = " . $this->addQuotes( $wgDBuser );
 259                         $rows = $this->numRows( $this->doQuery( $SQL ) );
 260                         if ( $rows ) {
 261                                 print '<li>User "' . htmlspecialchars( $wgDBuser ) . '" already exists, skipping account creation.</li>';
 262                         } else {
 263                                 if ( $perms != 1 && $perms != 3 ) {
 264                                         print '<li>ERROR: the user "' . htmlspecialchars( $superuser ) . '" cannot create other users. ';
 265                                         print 'Please use a different Postgres user.</li>';
 266                                         dieout( '' );
 267                                 }
 268                                 print '<li>Creating user <b>' . htmlspecialchars( $wgDBuser ) . '</b>...';
 269                                 $safepass = $this->addQuotes( $wgDBpassword );
 270                                 $SQL = "CREATE USER $safeuser NOCREATEDB PASSWORD $safepass";
 271                                 $this->doQuery( $SQL );
 272                                 print "OK</li>\n";
 273                         }
 274                         // User now exists, check out the database
 275                         if ( $dbName != $wgDBname ) {
 276                                 $SQL = "SELECT 1 FROM pg_catalog.pg_database WHERE datname = " . $this->addQuotes( $wgDBname );
 277                                 $rows = $this->numRows( $this->doQuery( $SQL ) );
 278                                 if ( $rows ) {
 279                                         print '<li>Database "' . htmlspecialchars( $wgDBname ) . '" already exists, skipping database creation.</li>';
 280                                 } else {
 281                                         if ( $perms < 1 ) {
 282                                                 print '<li>ERROR: the user "' . htmlspecialchars( $superuser ) . '" cannot create databases. ';
 283                                                 print 'Please use a different Postgres user.</li>';
 284                                                 dieout( '' );
 285                                         }
 286                                         print '<li>Creating database <b>' . htmlspecialchars( $wgDBname ) . '</b>...';
 287                                         $safename = $this->quote_ident( $wgDBname );
 288                                         $SQL = "CREATE DATABASE $safename OWNER $safeuser ";
 289                                         $this->doQuery( $SQL );
 290                                         print "OK</li>\n";
 291                                         // Hopefully tsearch2 and plpgsql are in template1...
 292                                 }
 293
 294                                 // Reconnect to check out tsearch2 rights for this user
 295                                 print '<li>Connecting to "' . htmlspecialchars( $wgDBname ) . '" as superuser "' .
 296                                         htmlspecialchars( $superuser ) . '" to check rights...';
 297
 298                                 $connectVars = array();
 299                                 if ( $this->mServer != false && $this->mServer != '' ) {
 300                                         $connectVars['host'] = $this->mServer;
 301                                 }
 302                                 if ( $this->mPort != false && $this->mPort != '' ) {
 303                                         $connectVars['port'] = $this->mPort;
 304                                 }
 305                                 $connectVars['dbname'] = $wgDBname;
 306                                 $connectVars['user'] = $superuser;
 307                                 $connectVars['password'] = $password;
 308
 309                                 @$this->mConn = pg_connect( $this->makeConnectionString( $connectVars ) );
 310                                 if ( !$this->mConn ) {
 311                                         print "<b>FAILED TO CONNECT!</b></li>";
 312                                         dieout( '' );
 313                                 }
 314                                 print "OK</li>\n";
 315                         }
 316
 317                         if ( $this->numeric_version < 8.3 ) {
 318                                 // Tsearch2 checks
 319                                 print '<li>Checking that tsearch2 is installed in the database "' .
 320                                         htmlspecialchars( $wgDBname ) . '"...';
 321                                 if ( !$this->tableExists( 'pg_ts_cfg', $wgDBts2schema ) ) {
 322                                         print '<b>FAILED</b>. tsearch2 must be installed in the database "' .
 323                                                 htmlspecialchars( $wgDBname ) . '".';
 324                                         print 'Please see <a href="http://www.devx.com/opensource/Article/21674/0/page/2">this article</a>';
 325                                         print " for instructions or ask on #postgresql on irc.freenode.net</li>\n";
 326                                         dieout( '' );
 327                                 }
 328                                 print "OK</li>\n";
 329                                 print '<li>Ensuring that user "' . htmlspecialchars( $wgDBuser ) .
 330                                         '" has select rights on the tsearch2 tables...';
 331                                 foreach ( array( 'cfg', 'cfgmap', 'dict', 'parser' ) as $table ) {
 332                                         $SQL = "GRANT SELECT ON pg_ts_$table TO $safeuser";
 333                                         $this->doQuery( $SQL );
 334                                 }
 335                                 print "OK</li>\n";
 336                         }
 337
 338                         // Setup the schema for this user if needed
 339                         $result = $this->schemaExists( $wgDBmwschema );
 340                         $safeschema = $this->quote_ident( $wgDBmwschema );
 341                         if ( !$result ) {
 342                                 print '<li>Creating schema <b>' . htmlspecialchars( $wgDBmwschema ) . '</b> ...';
 343                                 $result = $this->doQuery( "CREATE SCHEMA $safeschema AUTHORIZATION $safeuser" );
 344                                 if ( !$result ) {
 345                                         print "<b>FAILED</b>.</li>\n";
 346                                         dieout( '' );
 347                                 }
 348                                 print "OK</li>\n";
 349                         } else {
 350                                 print "<li>Schema already exists, explicitly granting rights...\n";
 351                                 $safeschema2 = $this->addQuotes( $wgDBmwschema );
 352                                 $SQL = "SELECT 'GRANT ALL ON '||pg_catalog.quote_ident(relname)||' TO $safeuser;'\n".
 353                                         "FROM pg_catalog.pg_class p, pg_catalog.pg_namespace n\n".
 354                                         "WHERE relnamespace = n.oid AND n.nspname = $safeschema2\n".
 355                                         "AND p.relkind IN ('r','S','v')\n";
 356                                 $SQL .= "UNION\n";
 357                                 $SQL .= "SELECT 'GRANT ALL ON FUNCTION '||pg_catalog.quote_ident(proname)||'('||\n".
 358                                         "pg_catalog.oidvectortypes(p.proargtypes)||') TO $safeuser;'\n".
 359                                         "FROM pg_catalog.pg_proc p, pg_catalog.pg_namespace n\n".
 360                                         "WHERE p.pronamespace = n.oid AND n.nspname = $safeschema2";
 361                                 $res = $this->doQuery( $SQL );
 362                                 if ( !$res ) {
 363                                         print "<b>FAILED</b>. Could not set rights for the user.</li>\n";
 364                                         dieout( '' );
 365                                 }
 366                                 $this->doQuery( "SET search_path = $safeschema" );
 367                                 $rows = $this->numRows( $res );
 368                                 while ( $rows ) {
 369                                         $rows--;
 370                                         $this->doQuery( pg_fetch_result( $res, $rows, 0 ) );
 371                                 }
 372                                 print "OK</li>";
 373                         }
 374
 375                         // Install plpgsql if needed
 376                         $this->setup_plpgsql();
 377
 378                         return true; // Reconnect as regular user
 379
 380                 } // end superuser
 381
 382                 if ( !defined( 'POSTGRES_SEARCHPATH' ) ) {
 383
 384                         if ( $this->numeric_version < 8.3 ) {
 385                                 // Do we have the basic tsearch2 table?
 386                                 print '<li>Checking for tsearch2 in the schema "' . htmlspecialchars( $wgDBts2schema ) . '"...';
 387                                 if ( !$this->tableExists( 'pg_ts_dict', $wgDBts2schema ) ) {
 388                                         print '<b>FAILED</b>. Make sure tsearch2 is installed. See <a href="';
 389                                         print 'http://www.devx.com/opensource/Article/21674/0/page/2">this article</a>';
 390                                         print " for instructions.</li>\n";
 391                                         dieout( '' );
 392                                 }
 393                                 print "OK</li>\n";
 394
 395                                 // Does this user have the rights to the tsearch2 tables?
 396                                 $ctype = pg_fetch_result( $this->doQuery( 'SHOW lc_ctype' ), 0, 0 );
 397                                 print '<li>Checking tsearch2 permissions...';
 398                                 // Let's check all four, just to be safe
 399                                 error_reporting( 0 );
 400                                 $ts2tables = array( 'cfg', 'cfgmap', 'dict', 'parser' );
 401                                 $safetsschema = $this->quote_ident( $wgDBts2schema );
 402                                 foreach ( $ts2tables as $tname ) {
 403                                         $SQL = "SELECT count(*) FROM $safetsschema.pg_ts_$tname";
 404                                         $res = $this->doQuery( $SQL );
 405                                         if ( !$res ) {
 406                                                 print "<b>FAILED</b> to access " . htmlspecialchars( "pg_ts_$tname" ) .
 407                                                         ". Make sure that the user \"". htmlspecialchars( $wgDBuser ) .
 408                                                         "\" has SELECT access to all four tsearch2 tables</li>\n";
 409                                                 dieout( '' );
 410                                         }
 411                                 }
 412                                 $SQL = "SELECT ts_name FROM $safetsschema.pg_ts_cfg WHERE locale = " . $this->addQuotes( $ctype ) ;
 413                                 $SQL .= " ORDER BY CASE WHEN ts_name <> 'default' THEN 1 ELSE 0 END";
 414                                 $res = $this->doQuery( $SQL );
 415                                 error_reporting( E_ALL );
 416                                 if ( !$res ) {
 417                                         print "<b>FAILED</b>. Could not determine the tsearch2 locale information</li>\n";
 418                                         dieout("</ul>");
 419                                 }
 420                                 print 'OK</li>';
 421
 422                                 // Will the current locale work? Can we force it to?
 423                                 print '<li>Verifying tsearch2 locale with ' . htmlspecialchars( $ctype ) . '...';
 424                                 $rows = $this->numRows( $res );
 425                                 $resetlocale = 0;
 426                                 if ( !$rows ) {
 427                                         print "<b>not found</b></li>\n";
 428                                         print '<li>Attempting to set default tsearch2 locale to "' . htmlspecialchars( $ctype ) . '"...';
 429                                         $resetlocale = 1;
 430                                 } else {
 431                                         $tsname = pg_fetch_result( $res, 0, 0 );
 432                                         if ( $tsname != 'default' ) {
 433                                                 print "<b>not set to default (" . htmlspecialchars( $tsname ) . ")</b>";
 434                                                 print "<li>Attempting to change tsearch2 default locale to \"" .
 435                                                         htmlspecialchars( $ctype ) . "\"...";
 436                                                 $resetlocale = 1;
 437                                         }
 438                                 }
 439                                 if ( $resetlocale ) {
 440                                         $SQL = "UPDATE $safetsschema.pg_ts_cfg SET locale = " . $this->addQuotes( $ctype ) . " WHERE ts_name = 'default'";
 441                                         $res = $this->doQuery( $SQL );
 442                                         if ( !$res ) {
 443                                                 print '<b>FAILED</b>. ';
 444                                                 print 'Please make sure that the locale in pg_ts_cfg for "default" is set to "' .
 445                                                         htmlspecialchars( $ctype ) . "\"</li>\n";
 446                                                 dieout( '' );
 447                                         }
 448                                         print 'OK</li>';
 449                                 }
 450
 451                                 // Final test: try out a simple tsearch2 query
 452                                 $SQL = "SELECT $safetsschema.to_tsvector('default','MediaWiki tsearch2 testing')";
 453                                 $res = $this->doQuery( $SQL );
 454                                 if ( !$res ) {
 455                                         print '<b>FAILED</b>. Specifically, "' . htmlspecialchars( $SQL ) . '" did not work.</li>';
 456                                         dieout( '' );
 457                                 }
 458                                 print 'OK</li>';
 459                         }
 460
 461                         // Install plpgsql if needed
 462                         $this->setup_plpgsql();
 463
 464                         // Does the schema already exist? Who owns it?
 465                         $result = $this->schemaExists( $wgDBmwschema );
 466                         if ( !$result ) {
 467                                 print '<li>Creating schema <b>' . htmlspecialchars( $wgDBmwschema ) . '</b> ...';
 468                                 error_reporting( 0 );
 469                                 $safeschema = $this->quote_ident( $wgDBmwschema );
 470                                 $result = $this->doQuery( "CREATE SCHEMA $safeschema" );
 471                                 error_reporting( E_ALL );
 472                                 if ( !$result ) {
 473                                         print '<b>FAILED</b>. The user "' . htmlspecialchars( $wgDBuser ) .
 474                                                 '" must be able to access the schema. '.
 475                                                 'You can try making them the owner of the database, or try creating the schema with a '.
 476                                                 'different user, and then grant access to the "' .
 477                                                 htmlspecialchars( $wgDBuser ) . "\" user.</li>\n";
 478                                         dieout( '' );
 479                                 }
 480                                 print "OK</li>\n";
 481                         } elseif ( $result != $wgDBuser ) {
 482                                 print '<li>Schema "' . htmlspecialchars( $wgDBmwschema ) . '" exists but is not owned by "' .
 483                                         htmlspecialchars( $wgDBuser ) . "\". Not ideal.</li>\n";
 484                         } else {
 485                                 print '<li>Schema "' . htmlspecialchars( $wgDBmwschema ) . '" exists and is owned by "' .
 486                                         htmlspecialchars( $wgDBuser ) . "\". Excellent.</li>\n";
 487                         }
 488
 489                         // Always return GMT time to accomodate the existing integer-based timestamp assumption
 490                         print "<li>Setting the timezone to GMT for user \"" . htmlspecialchars( $wgDBuser ) . '" ...';
 491                         $SQL = "ALTER USER $safeuser SET timezone = 'GMT'";
 492                         $result = pg_query( $this->mConn, $SQL );
 493                         if ( !$result ) {
 494                                 print "<b>FAILED</b>.</li>\n";
 495                                 dieout( '' );
 496                         }
 497                         print "OK</li>\n";
 498                         // Set for the rest of this session
 499                         $SQL = "SET timezone = 'GMT'";
 500                         $result = pg_query( $this->mConn, $SQL );
 501                         if ( !$result ) {
 502                                 print "<li>Failed to set timezone</li>\n";
 503                                 dieout( '' );
 504                         }
 505
 506                         print '<li>Setting the datestyle to ISO, YMD for user "' . htmlspecialchars( $wgDBuser ) . '" ...';
 507                         $SQL = "ALTER USER $safeuser SET datestyle = 'ISO, YMD'";
 508                         $result = pg_query( $this->mConn, $SQL );
 509                         if ( !$result ) {
 510                                 print "<b>FAILED</b>.</li>\n";
 511                                 dieout( '' );
 512                         }
 513                         print "OK</li>\n";
 514                         // Set for the rest of this session
 515                         $SQL = "SET datestyle = 'ISO, YMD'";
 516                         $result = pg_query( $this->mConn, $SQL );
 517                         if ( !$result ) {
 518                                 print "<li>Failed to set datestyle</li>\n";
 519                                 dieout( '' );
 520                         }
 521
 522                         // Fix up the search paths if needed
 523                         print '<li>Setting the search path for user "' . htmlspecialchars( $wgDBuser ) . '" ...';
 524                         $path = $this->quote_ident( $wgDBmwschema );
 525                         if ( $wgDBts2schema !== $wgDBmwschema ) {
 526                                 $path .= ', '. $this->quote_ident( $wgDBts2schema );
 527                         }
 528                         if ( $wgDBmwschema !== 'public' && $wgDBts2schema !== 'public' ) {
 529                                 $path .= ', public';
 530                         }
 531                         $SQL = "ALTER USER $safeuser SET search_path = $path";
 532                         $result = pg_query( $this->mConn, $SQL );
 533                         if ( !$result ) {
 534                                 print "<b>FAILED</b>.</li>\n";
 535                                 dieout( '' );
 536                         }
 537                         print "OK</li>\n";
 538                         // Set for the rest of this session
 539                         $SQL = "SET search_path = $path";
 540                         $result = pg_query( $this->mConn, $SQL );
 541                         if ( !$result ) {
 542                                 print "<li>Failed to set search_path</li>\n";
 543                                 dieout( '' );
 544                         }
 545                         define( 'POSTGRES_SEARCHPATH', $path );
 546                 }
 547         }
 548
 549         function setup_plpgsql() {
 550                 print '<li>Checking for PL/pgSQL ...';
 551                 $SQL = "SELECT 1 FROM pg_catalog.pg_language WHERE lanname = 'plpgsql'";
 552                 $rows = $this->numRows( $this->doQuery( $SQL ) );
 553                 if ( $rows < 1 ) {
 554                         // plpgsql is not installed, but if we have a pg_pltemplate table, we should be able to create it
 555                         print 'not installed. Attempting to install PL/pgSQL ...';
 556                         $SQL = "SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON (n.oid = c.relnamespace) ".
 557                                 "WHERE relname = 'pg_pltemplate' AND nspname='pg_catalog'";
 558                         $rows = $this->numRows( $this->doQuery( $SQL ) );
 559                         global $wgDBname;
 560                         if ( $rows >= 1 ) {
 561                                 $olde = error_reporting( 0 );
 562                                 error_reporting( $olde - E_WARNING );
 563                                 $result = $this->doQuery( 'CREATE LANGUAGE plpgsql' );
 564                                 error_reporting( $olde );
 565                                 if ( !$result ) {
 566                                         print '<b>FAILED</b>. You need to install the language PL/pgSQL in the database <tt>' .
 567                                                 htmlspecialchars( $wgDBname ) . '</tt></li>';
 568                                         dieout( '' );
 569                                 }
 570                         } else {
 571                                 print '<b>FAILED</b>. You need to install the language PL/pgSQL in the database <tt>' .
 572                                         htmlspecialchars( $wgDBname ) . '</tt></li>';
 573                                 dieout( '' );
 574                         }
 575                 }
 576                 print "OK</li>\n";
 577         }
 578
 579         /**
 580          * Closes a database connection, if it is open
 581          * Returns success, true if already closed
 582          */
 583         function close() {
 584                 $this->mOpened = false;
 585                 if ( $this->mConn ) {
 586                         return pg_close( $this->mConn );
 587                 } else {
 588                         return true;
 589                 }
 590         }
 591
 592         function doQuery( $sql ) {
 593                 if ( function_exists( 'mb_convert_encoding' ) ) {
 594                         $sql = mb_convert_encoding( $sql, 'UTF-8' );
 595                 }
 596                 $this->mLastResult = pg_query( $this->mConn, $sql );
 597                 $this->mAffectedRows = null; // use pg_affected_rows(mLastResult)
 598                 return $this->mLastResult;
 599         }
 600
 601         function queryIgnore( $sql, $fname = '' ) {
 602                 return $this->query( $sql, $fname, true );
 603         }
 604
 605         function freeResult( $res ) {
 606                 if ( $res instanceof ResultWrapper ) {
 607                         $res = $res->result;
 608                 }
 609                 if ( !@pg_free_result( $res ) ) {
 610                         throw new DBUnexpectedError( $this, "Unable to free Postgres result\n" );
 611                 }
 612         }
 613
 614         function fetchObject( $res ) {
 615                 if ( $res instanceof ResultWrapper ) {
 616                         $res = $res->result;
 617                 }
 618                 @$row = pg_fetch_object( $res );
 619                 # FIXME: HACK HACK HACK HACK debug
 620
 621                 # TODO:
 622                 # hashar : not sure if the following test really trigger if the object
 623                 #          fetching failed.
 624                 if( pg_last_error( $this->mConn ) ) {
 625                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 626                 }
 627                 return $row;
 628         }
 629
 630         function fetchRow( $res ) {
 631                 if ( $res instanceof ResultWrapper ) {
 632                         $res = $res->result;
 633                 }
 634                 @$row = pg_fetch_array( $res );
 635                 if( pg_last_error( $this->mConn ) ) {
 636                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 637                 }
 638                 return $row;
 639         }
 640
 641         function numRows( $res ) {
 642                 if ( $res instanceof ResultWrapper ) {
 643                         $res = $res->result;
 644                 }
 645                 @$n = pg_num_rows( $res );
 646                 if( pg_last_error( $this->mConn ) ) {
 647                         throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( pg_last_error( $this->mConn ) ) );
 648                 }
 649                 return $n;
 650         }
 651
 652         function numFields( $res ) {
 653                 if ( $res instanceof ResultWrapper ) {
 654                         $res = $res->result;
 655                 }
 656                 return pg_num_fields( $res );
 657         }
 658
 659         function fieldName( $res, $n ) {
 660                 if ( $res instanceof ResultWrapper ) {
 661                         $res = $res->result;
 662                 }
 663                 return pg_field_name( $res, $n );
 664         }
 665
 666         /**
 667          * This must be called after nextSequenceVal
 668          */
 669         function insertId() {
 670                 return $this->mInsertId;
 671         }
 672
 673         function dataSeek( $res, $row ) {
 674                 if ( $res instanceof ResultWrapper ) {
 675                         $res = $res->result;
 676                 }
 677                 return pg_result_seek( $res, $row );
 678         }
 679
 680         function lastError() {
 681                 if ( $this->mConn ) {
 682                         return pg_last_error();
 683                 } else {
 684                         return 'No database connection';
 685                 }
 686         }
 687         function lastErrno() {
 688                 return pg_last_error() ? 1 : 0;
 689         }
 690
 691         function affectedRows() {
 692                 if ( !is_null( $this->mAffectedRows ) ) {
 693                         // Forced result for simulated queries
 694                         return $this->mAffectedRows;
 695                 }
 696                 if( empty( $this->mLastResult ) ) {
 697                         return 0;
 698                 }
 699                 return pg_affected_rows( $this->mLastResult );
 700         }
 701
 702         /**
 703          * Estimate rows in dataset
 704          * Returns estimated count, based on EXPLAIN output
 705          * This is not necessarily an accurate estimate, so use sparingly
 706          * Returns -1 if count cannot be found
 707          * Takes same arguments as Database::select()
 708          */
 709         function estimateRowCount( $table, $vars = '*', $conds='', $fname = 'DatabasePostgres::estimateRowCount', $options = array() ) {
 710                 $options['EXPLAIN'] = true;
 711                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 712                 $rows = -1;
 713                 if ( $res ) {
 714                         $row = $this->fetchRow( $res );
 715                         $count = array();
 716                         if( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
 717                                 $rows = $count[1];
 718                         }
 719                 }
 720                 return $rows;
 721         }
 722
 723         /**
 724          * Returns information about an index
 725          * If errors are explicitly ignored, returns NULL on failure
 726          */
 727         function indexInfo( $table, $index, $fname = 'DatabasePostgres::indexInfo' ) {
 728                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 729                 $res = $this->query( $sql, $fname );
 730                 if ( !$res ) {
 731                         return null;
 732                 }
 733                 foreach ( $res as $row ) {
 734                         if ( $row->indexname == $this->indexName( $index ) ) {
 735                                 return $row;
 736                         }
 737                 }
 738                 return false;
 739         }
 740
 741         function indexUnique( $table, $index, $fname = 'DatabasePostgres::indexUnique' ) {
 742                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 743                         " AND indexdef LIKE 'CREATE UNIQUE%(" .
 744                         $this->strencode( $this->indexName( $index ) ) .
 745                         ")'";
 746                 $res = $this->query( $sql, $fname );
 747                 if ( !$res ) {
 748                         return null;
 749                 }
 750                 foreach ( $res as $row ) {
 751                         return true;
 752                 }
 753                 return false;
 754         }
 755
 756         /**
 757          * INSERT wrapper, inserts an array into a table
 758          *
 759          * $args may be a single associative array, or an array of these with numeric keys,
 760          * for multi-row insert (Postgres version 8.2 and above only).
 761          *
 762          * @param $table   String: Name of the table to insert to.
 763          * @param $args    Array: Items to insert into the table.
 764          * @param $fname   String: Name of the function, for profiling
 765          * @param $options String or Array. Valid options: IGNORE
 766          *
 767          * @return bool Success of insert operation. IGNORE always returns true.
 768          */
 769         function insert( $table, $args, $fname = 'DatabasePostgres::insert', $options = array() ) {
 770                 if ( !count( $args ) ) {
 771                         return true;
 772                 }
 773
 774                 $table = $this->tableName( $table );
 775                 if (! isset( $this->numeric_version ) ) {
 776                         $this->getServerVersion();
 777                 }
 778
 779                 if ( !is_array( $options ) ) {
 780                         $options = array( $options );
 781                 }
 782
 783                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 784                         $multi = true;
 785                         $keys = array_keys( $args[0] );
 786                 } else {
 787                         $multi = false;
 788                         $keys = array_keys( $args );
 789                 }
 790
 791                 // If IGNORE is set, we use savepoints to emulate mysql's behavior
 792                 $ignore = in_array( 'IGNORE', $options ) ? 'mw' : '';
 793
 794                 // If we are not in a transaction, we need to be for savepoint trickery
 795                 $didbegin = 0;
 796                 if ( $ignore ) {
 797                         if ( !$this->mTrxLevel ) {
 798                                 $this->begin();
 799                                 $didbegin = 1;
 800                         }
 801                         $olde = error_reporting( 0 );
 802                         // For future use, we may want to track the number of actual inserts
 803                         // Right now, insert (all writes) simply return true/false
 804                         $numrowsinserted = 0;
 805                 }
 806
 807                 $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 808
 809                 if ( $multi ) {
 810                         if ( $this->numeric_version >= 8.2 && !$ignore ) {
 811                                 $first = true;
 812                                 foreach ( $args as $row ) {
 813                                         if ( $first ) {
 814                                                 $first = false;
 815                                         } else {
 816                                                 $sql .= ',';
 817                                         }
 818                                         $sql .= '(' . $this->makeList( $row ) . ')';
 819                                 }
 820                                 $res = (bool)$this->query( $sql, $fname, $ignore );
 821                         } else {
 822                                 $res = true;
 823                                 $origsql = $sql;
 824                                 foreach ( $args as $row ) {
 825                                         $tempsql = $origsql;
 826                                         $tempsql .= '(' . $this->makeList( $row ) . ')';
 827
 828                                         if ( $ignore ) {
 829                                                 pg_query( $this->mConn, "SAVEPOINT $ignore" );
 830                                         }
 831
 832                                         $tempres = (bool)$this->query( $tempsql, $fname, $ignore );
 833
 834                                         if ( $ignore ) {
 835                                                 $bar = pg_last_error();
 836                                                 if ( $bar != false ) {
 837                                                         pg_query( $this->mConn, "ROLLBACK TO $ignore" );
 838                                                 } else {
 839                                                         pg_query( $this->mConn, "RELEASE $ignore" );
 840                                                         $numrowsinserted++;
 841                                                 }
 842                                         }
 843
 844                                         // If any of them fail, we fail overall for this function call
 845                                         // Note that this will be ignored if IGNORE is set
 846                                         if ( !$tempres ) {
 847                                                 $res = false;
 848                                         }
 849                                 }
 850                         }
 851                 } else {
 852                         // Not multi, just a lone insert
 853                         if ( $ignore ) {
 854                                 pg_query($this->mConn, "SAVEPOINT $ignore");
 855                         }
 856
 857                         $sql .= '(' . $this->makeList( $args ) . ')';
 858                         $res = (bool)$this->query( $sql, $fname, $ignore );
 859                         if ( $ignore ) {
 860                                 $bar = pg_last_error();
 861                                 if ( $bar != false ) {
 862                                         pg_query( $this->mConn, "ROLLBACK TO $ignore" );
 863                                 } else {
 864                                         pg_query( $this->mConn, "RELEASE $ignore" );
 865                                         $numrowsinserted++;
 866                                 }
 867                         }
 868                 }
 869                 if ( $ignore ) {
 870                         $olde = error_reporting( $olde );
 871                         if ( $didbegin ) {
 872                                 $this->commit();
 873                         }
 874
 875                         // Set the affected row count for the whole operation
 876                         $this->mAffectedRows = $numrowsinserted;
 877
 878                         // IGNORE always returns true
 879                         return true;
 880                 }
 881
 882                 return $res;
 883         }
 884
 885         /**
 886          * INSERT SELECT wrapper
 887          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
 888          * Source items may be literals rather then field names, but strings should be quoted with Database::addQuotes()
 889          * $conds may be "*" to copy the whole table
 890          * srcTable may be an array of tables.
 891          * @todo FIXME: implement this a little better (seperate select/insert)?
 892          */
 893         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'DatabasePostgres::insertSelect',
 894                 $insertOptions = array(), $selectOptions = array() )
 895         {
 896                 $destTable = $this->tableName( $destTable );
 897
 898                 // If IGNORE is set, we use savepoints to emulate mysql's behavior
 899                 $ignore = in_array( 'IGNORE', $insertOptions ) ? 'mw' : '';
 900
 901                 if( is_array( $insertOptions ) ) {
 902                         $insertOptions = implode( ' ', $insertOptions );
 903                 }
 904                 if( !is_array( $selectOptions ) ) {
 905                         $selectOptions = array( $selectOptions );
 906                 }
 907                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
 908                 if( is_array( $srcTable ) ) {
 909                         $srcTable = implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
 910                 } else {
 911                         $srcTable = $this->tableName( $srcTable );
 912                 }
 913
 914                 // If we are not in a transaction, we need to be for savepoint trickery
 915                 $didbegin = 0;
 916                 if ( $ignore ) {
 917                         if( !$this->mTrxLevel ) {
 918                                 $this->begin();
 919                                 $didbegin = 1;
 920                         }
 921                         $olde = error_reporting( 0 );
 922                         $numrowsinserted = 0;
 923                         pg_query( $this->mConn, "SAVEPOINT $ignore");
 924                 }
 925
 926                 $sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
 927                                 " SELECT $startOpts " . implode( ',', $varMap ) .
 928                                 " FROM $srcTable $useIndex";
 929
 930                 if ( $conds != '*' ) {
 931                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
 932                 }
 933
 934                 $sql .= " $tailOpts";
 935
 936                 $res = (bool)$this->query( $sql, $fname, $ignore );
 937                 if( $ignore ) {
 938                         $bar = pg_last_error();
 939                         if( $bar != false ) {
 940                                 pg_query( $this->mConn, "ROLLBACK TO $ignore" );
 941                         } else {
 942                                 pg_query( $this->mConn, "RELEASE $ignore" );
 943                                 $numrowsinserted++;
 944                         }
 945                         $olde = error_reporting( $olde );
 946                         if( $didbegin ) {
 947                                 $this->commit();
 948                         }
 949
 950                         // Set the affected row count for the whole operation
 951                         $this->mAffectedRows = $numrowsinserted;
 952
 953                         // IGNORE always returns true
 954                         return true;
 955                 }
 956
 957                 return $res;
 958         }
 959
 960         function tableName( $name ) {
 961                 # Replace reserved words with better ones
 962                 switch( $name ) {
 963                         case 'user':
 964                                 return 'mwuser';
 965                         case 'text':
 966                                 return 'pagecontent';
 967                         default:
 968                                 return $name;
 969                 }
 970         }
 971
 972         /**
 973          * Return the next in a sequence, save the value for retrieval via insertId()
 974          */
 975         function nextSequenceValue( $seqName ) {
 976                 $safeseq = preg_replace( "/'/", "''", $seqName );
 977                 $res = $this->query( "SELECT nextval('$safeseq')" );
 978                 $row = $this->fetchRow( $res );
 979                 $this->mInsertId = $row[0];
 980                 return $this->mInsertId;
 981         }
 982
 983         /**
 984          * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
 985          */
 986         function currentSequenceValue( $seqName ) {
 987                 $safeseq = preg_replace( "/'/", "''", $seqName );
 988                 $res = $this->query( "SELECT currval('$safeseq')" );
 989                 $row = $this->fetchRow( $res );
 990                 $currval = $row[0];
 991                 return $currval;
 992         }
 993
 994         /**
 995          * REPLACE query wrapper
 996          * Postgres simulates this with a DELETE followed by INSERT
 997          * $row is the row to insert, an associative array
 998          * $uniqueIndexes is an array of indexes. Each element may be either a
 999          * field name or an array of field names
1000          *
1001          * It may be more efficient to leave off unique indexes which are unlikely to collide.
1002          * However if you do this, you run the risk of encountering errors which wouldn't have
1003          * occurred in MySQL
1004          */
1005         function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabasePostgres::replace' ) {
1006                 $table = $this->tableName( $table );
1007
1008                 if ( count( $rows ) == 0 ) {
1009                         return;
1010                 }
1011
1012                 # Single row case
1013                 if ( !is_array( reset( $rows ) ) ) {
1014                         $rows = array( $rows );
1015                 }
1016
1017                 foreach( $rows as $row ) {
1018                         # Delete rows which collide
1019                         if ( $uniqueIndexes ) {
1020                                 $sql = "DELETE FROM $table WHERE ";
1021                                 $first = true;
1022                                 foreach ( $uniqueIndexes as $index ) {
1023                                         if ( $first ) {
1024                                                 $first = false;
1025                                                 $sql .= '(';
1026                                         } else {
1027                                                 $sql .= ') OR (';
1028                                         }
1029                                         if ( is_array( $index ) ) {
1030                                                 $first2 = true;
1031                                                 foreach ( $index as $col ) {
1032                                                         if ( $first2 ) {
1033                                                                 $first2 = false;
1034                                                         } else {
1035                                                                 $sql .= ' AND ';
1036                                                         }
1037                                                         $sql .= $col.'=' . $this->addQuotes( $row[$col] );
1038                                                 }
1039                                         } else {
1040                                                 $sql .= $index.'=' . $this->addQuotes( $row[$index] );
1041                                         }
1042                                 }
1043                                 $sql .= ')';
1044                                 $this->query( $sql, $fname );
1045                         }
1046
1047                         # Now insert the row
1048                         $sql = "INSERT INTO $table (" . $this->makeList( array_keys( $row ), LIST_NAMES ) .') VALUES (' .
1049                                 $this->makeList( $row, LIST_COMMA ) . ')';
1050                         $this->query( $sql, $fname );
1051                 }
1052         }
1053
1054         # DELETE where the condition is a join
1055         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'DatabasePostgres::deleteJoin' ) {
1056                 if ( !$conds ) {
1057                         throw new DBUnexpectedError( $this, 'DatabasePostgres::deleteJoin() called with empty $conds' );
1058                 }
1059
1060                 $delTable = $this->tableName( $delTable );
1061                 $joinTable = $this->tableName( $joinTable );
1062                 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
1063                 if ( $conds != '*' ) {
1064                         $sql .= 'WHERE ' . $this->makeList( $conds, LIST_AND );
1065                 }
1066                 $sql .= ')';
1067
1068                 $this->query( $sql, $fname );
1069         }
1070
1071         # Returns the size of a text field, or -1 for "unlimited"
1072         function textFieldSize( $table, $field ) {
1073                 $table = $this->tableName( $table );
1074                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
1075                         FROM pg_class c, pg_attribute a, pg_type t
1076                         WHERE relname='$table' AND a.attrelid=c.oid AND
1077                                 a.atttypid=t.oid and a.attname='$field'";
1078                 $res =$this->query( $sql );
1079                 $row = $this->fetchObject( $res );
1080                 if ( $row->ftype == 'varchar' ) {
1081                         $size = $row->size - 4;
1082                 } else {
1083                         $size = $row->size;
1084                 }
1085                 return $size;
1086         }
1087
1088         function limitResult( $sql, $limit, $offset = false ) {
1089                 return "$sql LIMIT $limit " . ( is_numeric( $offset ) ? " OFFSET {$offset} " : '' );
1090         }
1091
1092         function wasDeadlock() {
1093                 return $this->lastErrno() == '40P01';
1094         }
1095
1096         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabasePostgres::duplicateTableStructure' ) {
1097                 return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName (LIKE $oldName INCLUDING DEFAULTS)", $fname );
1098         }
1099
1100         function timestamp( $ts = 0 ) {
1101                 return wfTimestamp( TS_POSTGRES, $ts );
1102         }
1103
1104         /**
1105          * Return aggregated value function call
1106          */
1107         function aggregateValue( $valuedata, $valuename = 'value' ) {
1108                 return $valuedata;
1109         }
1110
1111         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
1112                 // Ignore errors during error handling to avoid infinite recursion
1113                 $ignore = $this->ignoreErrors( true );
1114                 $this->mErrorCount++;
1115
1116                 if ( $ignore || $tempIgnore ) {
1117                         wfDebug( "SQL ERROR (ignored): $error\n" );
1118                         $this->ignoreErrors( $ignore );
1119                 } else {
1120                         $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" .
1121                                 "Query: $sql\n" .
1122                                 "Function: $fname\n" .
1123                                 "Error: $errno $error\n";
1124                         throw new DBUnexpectedError( $this, $message );
1125                 }
1126         }
1127
1128         /**
1129          * @return string wikitext of a link to the server software's web site
1130          */
1131         public static function getSoftwareLink() {
1132                 return '[http://www.postgresql.org/ PostgreSQL]';
1133         }
1134
1135         /**
1136          * @return string Version information from the database
1137          */
1138         function getServerVersion() {
1139                 if ( !isset( $this->numeric_version ) ) {
1140                         $versionInfo = pg_version( $this->mConn );
1141                         if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
1142                                 // Old client, abort install
1143                                 $this->numeric_version = '7.3 or earlier';
1144                         } elseif ( isset( $versionInfo['server'] ) ) {
1145                                 // Normal client
1146                                 $this->numeric_version = $versionInfo['server'];
1147                         } else {
1148                                 // Bug 16937: broken pgsql extension from PHP<5.3
1149                                 $this->numeric_version = pg_parameter_status( $this->mConn, 'server_version' );
1150                         }
1151                 }
1152                 return $this->numeric_version;
1153         }
1154
1155         /**
1156          * Query whether a given relation exists (in the given schema, or the
1157          * default mw one if not given)
1158          */
1159         function relationExists( $table, $types, $schema = false ) {
1160                 global $wgDBmwschema;
1161                 if ( !is_array( $types ) ) {
1162                         $types = array( $types );
1163                 }
1164                 if ( !$schema ) {
1165                         $schema = $wgDBmwschema;
1166                 }
1167                 $etable = $this->addQuotes( $table );
1168                 $eschema = $this->addQuotes( $schema );
1169                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
1170                         . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
1171                         . "AND c.relkind IN ('" . implode( "','", $types ) . "')";
1172                 $res = $this->query( $SQL );
1173                 $count = $res ? $res->numRows() : 0;
1174                 return (bool)$count;
1175         }
1176
1177         /**
1178          * For backward compatibility, this function checks both tables and
1179          * views.
1180          */
1181         function tableExists( $table, $schema = false ) {
1182                 return $this->relationExists( $table, array( 'r', 'v' ), $schema );
1183         }
1184
1185         function sequenceExists( $sequence, $schema = false ) {
1186                 return $this->relationExists( $sequence, 'S', $schema );
1187         }
1188
1189         function triggerExists( $table, $trigger ) {
1190                 global $wgDBmwschema;
1191
1192                 $q = <<<SQL
1193         SELECT 1 FROM pg_class, pg_namespace, pg_trigger
1194                 WHERE relnamespace=pg_namespace.oid AND relkind='r'
1195                       AND tgrelid=pg_class.oid
1196                       AND nspname=%s AND relname=%s AND tgname=%s
1197 SQL;
1198                 $res = $this->query(
1199                         sprintf(
1200                                 $q,
1201                                 $this->addQuotes( $wgDBmwschema ),
1202                                 $this->addQuotes( $table ),
1203                                 $this->addQuotes( $trigger )
1204                         )
1205                 );
1206                 if ( !$res ) {
1207                         return null;
1208                 }
1209                 $rows = $res->numRows();
1210                 return $rows;
1211         }
1212
1213         function ruleExists( $table, $rule ) {
1214                 global $wgDBmwschema;
1215                 $exists = $this->selectField( 'pg_rules', 'rulename',
1216                         array(
1217                                 'rulename' => $rule,
1218                                 'tablename' => $table,
1219                                 'schemaname' => $wgDBmwschema
1220                         )
1221                 );
1222                 return $exists === $rule;
1223         }
1224
1225         function constraintExists( $table, $constraint ) {
1226                 global $wgDBmwschema;
1227                 $SQL = sprintf( "SELECT 1 FROM information_schema.table_constraints ".
1228                            "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
1229                         $this->addQuotes( $wgDBmwschema ),
1230                         $this->addQuotes( $table ),
1231                         $this->addQuotes( $constraint )
1232                 );
1233                 $res = $this->query( $SQL );
1234                 if ( !$res ) {
1235                         return null;
1236                 }
1237                 $rows = $res->numRows();
1238                 return $rows;
1239         }
1240
1241         /**
1242          * Query whether a given schema exists. Returns the name of the owner
1243          */
1244         function schemaExists( $schema ) {
1245                 $eschema = preg_replace( "/'/", "''", $schema );
1246                 $SQL = "SELECT rolname FROM pg_catalog.pg_namespace n, pg_catalog.pg_roles r "
1247                                 ."WHERE n.nspowner=r.oid AND n.nspname = '$eschema'";
1248                 $res = $this->query( $SQL );
1249                 if ( $res && $res->numRows() ) {
1250                         $row = $res->fetchObject();
1251                         $owner = $row->rolname;
1252                 } else {
1253                         $owner = false;
1254                 }
1255                 return $owner;
1256         }
1257
1258         function fieldInfo( $table, $field ) {
1259                 return PostgresField::fromText( $this, $table, $field );
1260         }
1261
1262         /**
1263          * pg_field_type() wrapper
1264          */
1265         function fieldType( $res, $index ) {
1266                 if ( $res instanceof ResultWrapper ) {
1267                         $res = $res->result;
1268                 }
1269                 return pg_field_type( $res, $index );
1270         }
1271
1272         /* Not even sure why this is used in the main codebase... */
1273         function limitResultForUpdate( $sql, $num ) {
1274                 return $sql;
1275         }
1276
1277         function encodeBlob( $b ) {
1278                 return new Blob( pg_escape_bytea( $this->mConn, $b ) );
1279         }
1280
1281         function decodeBlob( $b ) {
1282                 if ( $b instanceof Blob ) {
1283                         $b = $b->fetch();
1284                 }
1285                 return pg_unescape_bytea( $b );
1286         }
1287
1288         function strencode( $s ) { # Should not be called by us
1289                 return pg_escape_string( $this->mConn, $s );
1290         }
1291
1292         function addQuotes( $s ) {
1293                 if ( is_null( $s ) ) {
1294                         return 'NULL';
1295                 } elseif ( is_bool( $s ) ) {
1296                         return intval( $s );
1297                 } elseif ( $s instanceof Blob ) {
1298                         return "'" . $s->fetch( $s ) . "'";
1299                 }
1300                 return "'" . pg_escape_string( $this->mConn, $s ) . "'";
1301         }
1302
1303         function quote_ident( $s ) {
1304                 return '"' . preg_replace( '/"/', '""', $s ) . '"';
1305         }
1306
1307         /**
1308          * Postgres specific version of replaceVars.
1309          * Calls the parent version in Database.php
1310          *
1311          * @private
1312          *
1313          * @param $ins String: SQL string, read from a stream (usually tables.sql)
1314          *
1315          * @return string SQL string
1316          */
1317         protected function replaceVars( $ins ) {
1318                 $ins = parent::replaceVars( $ins );
1319
1320                 if ( $this->numeric_version >= 8.3 ) {
1321                         // Thanks for not providing backwards-compatibility, 8.3
1322                         $ins = preg_replace( "/to_tsvector\s*\(\s*'default'\s*,/", 'to_tsvector(', $ins );
1323                 }
1324
1325                 if ( $this->numeric_version <= 8.1 ) { // Our minimum version
1326                         $ins = str_replace( 'USING gin', 'USING gist', $ins );
1327                 }
1328
1329                 return $ins;
1330         }
1331
1332         /**
1333          * Various select options
1334          *
1335          * @private
1336          *
1337          * @param $options Array: an associative array of options to be turned into
1338          *              an SQL query, valid keys are listed in the function.
1339          * @return array
1340          */
1341         function makeSelectOptions( $options ) {
1342                 $preLimitTail = $postLimitTail = '';
1343                 $startOpts = $useIndex = '';
1344
1345                 $noKeyOptions = array();
1346                 foreach ( $options as $key => $option ) {
1347                         if ( is_numeric( $key ) ) {
1348                                 $noKeyOptions[$option] = true;
1349                         }
1350                 }
1351
1352                 if ( isset( $options['GROUP BY'] ) ) {
1353                         $preLimitTail .= ' GROUP BY ' . $options['GROUP BY'];
1354                 }
1355                 if ( isset( $options['HAVING'] ) ) {
1356                         $preLimitTail .= " HAVING {$options['HAVING']}";
1357                 }
1358                 if ( isset( $options['ORDER BY'] ) ) {
1359                         $preLimitTail .= ' ORDER BY ' . $options['ORDER BY'];
1360                 }
1361
1362                 //if ( isset( $options['LIMIT'] ) ) {
1363                 //      $tailOpts .= $this->limitResult( '', $options['LIMIT'],
1364                 //              isset( $options['OFFSET'] ) ? $options['OFFSET']
1365                 //              : false );
1366                 //}
1367
1368                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1369                         $postLimitTail .= ' FOR UPDATE';
1370                 }
1371                 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1372                         $postLimitTail .= ' LOCK IN SHARE MODE';
1373                 }
1374                 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1375                         $startOpts .= 'DISTINCT';
1376                 }
1377
1378                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1379         }
1380
1381         function setFakeMaster( $enabled = true ) {}
1382
1383         function getDBname() {
1384                 return $this->mDBname;
1385         }
1386
1387         function getServer() {
1388                 return $this->mServer;
1389         }
1390
1391         function buildConcat( $stringList ) {
1392                 return implode( ' || ', $stringList );
1393         }
1394
1395         public function getSearchEngine() {
1396                 return 'SearchPostgres';
1397         }
1398 } // end DatabasePostgres class