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