includes/DatabasePostgres.php

   1 <?php
   2
   3 /**
   4  * This is the Postgres database abstraction layer.
   5  *
   6  * As it includes more generic version for DB functions,
   7  * than MySQL ones, some of them should be moved to parent
   8  * Database class.
   9  *
  10  * @addtogroup Database
  11  */
  12 class PostgresField {
  13         private $name, $tablename, $type, $nullable, $max_length;
  14
  15         static function fromText($db, $table, $field) {
  16         global $wgDBmwschema;
  17
  18                 $q = <<<END
  19 SELECT typname, attnotnull, attlen
  20 FROM pg_class, pg_namespace, pg_attribute, pg_type
  21 WHERE relnamespace=pg_namespace.oid
  22 AND relkind='r'
  23 AND attrelid=pg_class.oid
  24 AND atttypid=pg_type.oid
  25 AND nspname=%s
  26 AND relname=%s
  27 AND attname=%s;
  28 END;
  29                 $res = $db->query(sprintf($q,
  30                                 $db->addQuotes($wgDBmwschema),
  31                                 $db->addQuotes($table),
  32                                 $db->addQuotes($field)));
  33                 $row = $db->fetchObject($res);
  34                 if (!$row)
  35                         return null;
  36                 $n = new PostgresField;
  37                 $n->type = $row->typname;
  38                 $n->nullable = ($row->attnotnull == 'f');
  39                 $n->name = $field;
  40                 $n->tablename = $table;
  41                 $n->max_length = $row->attlen;
  42                 return $n;
  43         }
  44
  45         function name() {
  46                 return $this->name;
  47         }
  48
  49         function tableName() {
  50                 return $this->tablename;
  51         }
  52
  53         function type() {
  54                 return $this->type;
  55         }
  56
  57         function nullable() {
  58                 return $this->nullable;
  59         }
  60
  61         function maxLength() {
  62                 return $this->max_length;
  63         }
  64 }
  65
  66 /**
  67  * @addtogroup Database
  68  */
  69 class DatabasePostgres extends Database {
  70         var $mInsertId = NULL;
  71         var $mLastResult = NULL;
  72         var $numeric_version = NULL;
  73
  74         function DatabasePostgres($server = false, $user = false, $password = false, $dbName = false,
  75                 $failFunction = false, $flags = 0 )
  76         {
  77
  78                 global $wgOut;
  79                 # Can't get a reference if it hasn't been set yet
  80                 if ( !isset( $wgOut ) ) {
  81                         $wgOut = NULL;
  82                 }
  83                 $this->mOut =& $wgOut;
  84                 $this->mFailFunction = $failFunction;
  85                 $this->mFlags = $flags;
  86                 $this->open( $server, $user, $password, $dbName);
  87
  88         }
  89
  90         function cascadingDeletes() {
  91                 return true;
  92         }
  93         function cleanupTriggers() {
  94                 return true;
  95         }
  96         function strictIPs() {
  97                 return true;
  98         }
  99         function realTimestamps() {
 100                 return true;
 101         }
 102         function implicitGroupby() {
 103                 return false;
 104         }
 105         function searchableIPs() {
 106                 return true;
 107         }
 108
 109         static function newFromParams( $server, $user, $password, $dbName, $failFunction = false, $flags = 0)
 110         {
 111                 return new DatabasePostgres( $server, $user, $password, $dbName, $failFunction, $flags );
 112         }
 113
 114         /**
 115          * Usually aborts on failure
 116          * If the failFunction is set to a non-zero integer, returns success
 117          */
 118         function open( $server, $user, $password, $dbName ) {
 119                 # Test for Postgres support, to avoid suppressed fatal error
 120                 if ( !function_exists( 'pg_connect' ) ) {
 121                         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" );
 122                 }
 123
 124                 global $wgDBport;
 125
 126                 if (!strlen($user)) { ## e.g. the class is being loaded
 127                         return;
 128                 }
 129
 130                 $this->close();
 131                 $this->mServer = $server;
 132                 $port = $wgDBport;
 133                 $this->mUser = $user;
 134                 $this->mPassword = $password;
 135                 $this->mDBname = $dbName;
 136
 137                 $hstring="";
 138                 if ($server!=false && $server!="") {
 139                         $hstring="host=$server ";
 140                 }
 141                 if ($port!=false && $port!="") {
 142                         $hstring .= "port=$port ";
 143                 }
 144
 145
 146                 error_reporting( E_ALL );
 147                 @$this->mConn = pg_connect("$hstring dbname=$dbName user=$user password=$password");
 148
 149                 if ( $this->mConn == false ) {
 150                         wfDebug( "DB connection error\n" );
 151                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
 152                         wfDebug( $this->lastError()."\n" );
 153                         return false;
 154                 }
 155
 156                 $this->mOpened = true;
 157                 ## If this is the initial connection, setup the schema stuff and possibly create the user
 158                 ## TODO: Move this out of open()
 159                 if (defined('MEDIAWIKI_INSTALL')) {
 160                         global $wgDBname, $wgDBuser, $wgDBpassword, $wgDBsuperuser, $wgDBmwschema,
 161                                 $wgDBts2schema;
 162
 163                         print "<li>Checking the version of Postgres...";
 164                         $version = $this->getServerVersion();
 165                         $PGMINVER = "8.1";
 166                         if ($this->numeric_version < $PGMINVER) {
 167                                 print "<b>FAILED</b>. Required version is $PGMINVER. You have $this->numeric_version ($version)</li>\n";
 168                                 dieout("</ul>");
 169                         }
 170                         print "version $this->numeric_version is OK.</li>\n";
 171
 172                         $safeuser = $this->quote_ident($wgDBuser);
 173                         ## Are we connecting as a superuser for the first time?
 174                         if ($wgDBsuperuser) {
 175                                 ## Are we really a superuser? Check out our rights
 176                                 $SQL = "SELECT
 177                                                 CASE WHEN usesuper IS TRUE THEN
 178                                                         CASE WHEN usecreatedb IS TRUE THEN 3 ELSE 1 END
 179                                                         ELSE CASE WHEN usecreatedb IS TRUE THEN 2 ELSE 0 END
 180                         END AS rights
 181                                                 FROM pg_catalog.pg_user WHERE usename = " . $this->addQuotes($wgDBsuperuser);
 182                                 $rows = $this->numRows($res = $this->doQuery($SQL));
 183                                 if (!$rows) {
 184                                         print "<li>ERROR: Could not read permissions for user \"$wgDBsuperuser\"</li>\n";
 185                                         dieout('</ul>');
 186                                 }
 187                                 $perms = pg_fetch_result($res, 0, 0);
 188
 189                                 $SQL = "SELECT 1 FROM pg_catalog.pg_user WHERE usename = " . $this->addQuotes($wgDBuser);
 190                                 $rows = $this->numRows($this->doQuery($SQL));
 191                                 if ($rows) {
 192                                         print "<li>User \"$wgDBuser\" already exists, skipping account creation.</li>";
 193                                 }
 194                                 else {
 195                                         if ($perms != 1 and $perms != 3) {
 196                                                 print "<li>ERROR: the user \"$wgDBsuperuser\" cannot create other users. ";
 197                                                 print 'Please use a different Postgres user.</li>';
 198                                                 dieout('</ul>');
 199                                         }
 200                                         print "<li>Creating user <b>$wgDBuser</b>...";
 201                                         $safepass = $this->addQuotes($wgDBpassword);
 202                                         $SQL = "CREATE USER $safeuser NOCREATEDB PASSWORD $safepass";
 203                                         $this->doQuery($SQL);
 204                                         print "OK</li>\n";
 205                                 }
 206                                 ## User now exists, check out the database
 207                                 if ($dbName != $wgDBname) {
 208                                         $SQL = "SELECT 1 FROM pg_catalog.pg_database WHERE datname = " . $this->addQuotes($wgDBname);
 209                                         $rows = $this->numRows($this->doQuery($SQL));
 210                                         if ($rows) {
 211                                                 print "<li>Database \"$wgDBname\" already exists, skipping database creation.</li>";
 212                                         }
 213                                         else {
 214                                                 if ($perms < 2) {
 215                                                         print "<li>ERROR: the user \"$wgDBsuperuser\" cannot create databases. ";
 216                                                         print 'Please use a different Postgres user.</li>';
 217                                                         dieout('</ul>');
 218                                                 }
 219                                                 print "<li>Creating database <b>$wgDBname</b>...";
 220                                                 $safename = $this->quote_ident($wgDBname);
 221                                                 $SQL = "CREATE DATABASE $safename OWNER $safeuser ";
 222                                                 $this->doQuery($SQL);
 223                                                 print "OK</li>\n";
 224                                                 ## Hopefully tsearch2 and plpgsql are in template1...
 225                                         }
 226
 227                                         ## Reconnect to check out tsearch2 rights for this user
 228                                         print "<li>Connecting to \"$wgDBname\" as superuser \"$wgDBsuperuser\" to check rights...";
 229                                         @$this->mConn = pg_connect("$hstring dbname=$wgDBname user=$user password=$password");
 230                                         if ( $this->mConn == false ) {
 231                                                 print "<b>FAILED TO CONNECT!</b></li>";
 232                                                 dieout("</ul>");
 233                                         }
 234                                         print "OK</li>\n";
 235                                 }
 236
 237                                 ## Tsearch2 checks
 238                                 print "<li>Checking that tsearch2 is installed in the database \"$wgDBname\"...";
 239                                 if (! $this->tableExists("pg_ts_cfg", $wgDBts2schema)) {
 240                                         print "<b>FAILED</b>. tsearch2 must be installed in the database \"$wgDBname\".";
 241                                         print "Please see <a href='http://www.devx.com/opensource/Article/21674/0/page/2'>this article</a>";
 242                                         print " for instructions or ask on #postgresql on irc.freenode.net</li>\n";
 243                                         dieout("</ul>");
 244                                 }
 245                                 print "OK</li>\n";
 246                                 print "<li>Ensuring that user \"$wgDBuser\" has select rights on the tsearch2 tables...";
 247                                 foreach (array('cfg','cfgmap','dict','parser') as $table) {
 248                                         $SQL = "GRANT SELECT ON pg_ts_$table TO $safeuser";
 249                                         $this->doQuery($SQL);
 250                                 }
 251                                 print "OK</li>\n";
 252
 253
 254                                 ## Setup the schema for this user if needed
 255                                 $result = $this->schemaExists($wgDBmwschema);
 256                                 $safeschema = $this->quote_ident($wgDBmwschema);
 257                                 if (!$result) {
 258                                         print "<li>Creating schema <b>$wgDBmwschema</b> ...";
 259                                         $result = $this->doQuery("CREATE SCHEMA $safeschema AUTHORIZATION $safeuser");
 260                                         if (!$result) {
 261                                                 print "<b>FAILED</b>.</li>\n";
 262                                                 dieout("</ul>");
 263                                         }
 264                                         print "OK</li>\n";
 265                                 }
 266                                 else {
 267                                         print "<li>Schema already exists, explicitly granting rights...\n";
 268                                         $safeschema2 = $this->addQuotes($wgDBmwschema);
 269                                         $SQL = "SELECT 'GRANT ALL ON '||pg_catalog.quote_ident(relname)||' TO $safeuser;'\n".
 270                                                         "FROM pg_catalog.pg_class p, pg_catalog.pg_namespace n\n".
 271                                                         "WHERE relnamespace = n.oid AND n.nspname = $safeschema2\n".
 272                                                         "AND p.relkind IN ('r','S','v')\n";
 273                                         $SQL .= "UNION\n";
 274                                         $SQL .= "SELECT 'GRANT ALL ON FUNCTION '||pg_catalog.quote_ident(proname)||'('||\n".
 275                                                         "pg_catalog.oidvectortypes(p.proargtypes)||') TO $safeuser;'\n".
 276                                                         "FROM pg_catalog.pg_proc p, pg_catalog.pg_namespace n\n".
 277                                                         "WHERE p.pronamespace = n.oid AND n.nspname = $safeschema2";
 278                                         $res = $this->doQuery($SQL);
 279                                         if (!$res) {
 280                                                 print "<b>FAILED</b>. Could not set rights for the user.</li>\n";
 281                                                 dieout("</ul>");
 282                                         }
 283                                         $this->doQuery("SET search_path = $safeschema");
 284                                         $rows = $this->numRows($res);
 285                                         while ($rows) {
 286                                                 $rows--;
 287                                                 $this->doQuery(pg_fetch_result($res, $rows, 0));
 288                                         }
 289                                         print "OK</li>";
 290                                 }
 291
 292                                 $wgDBsuperuser = '';
 293                                 return true; ## Reconnect as regular user
 294
 295                         } ## end superuser
 296
 297                 if (!defined('POSTGRES_SEARCHPATH')) {
 298
 299                         ## Do we have the basic tsearch2 table?
 300                         print "<li>Checking for tsearch2 in the schema \"$wgDBts2schema\"...";
 301                         if (! $this->tableExists("pg_ts_dict", $wgDBts2schema)) {
 302                                 print "<b>FAILED</b>. Make sure tsearch2 is installed. See <a href=";
 303                                 print "'http://www.devx.com/opensource/Article/21674/0/page/2'>this article</a>";
 304                                 print " for instructions.</li>\n";
 305                                 dieout("</ul>");
 306                         }
 307                         print "OK</li>\n";
 308
 309                         ## Does this user have the rights to the tsearch2 tables?
 310                         $ctype = pg_fetch_result($this->doQuery("SHOW lc_ctype"),0,0);
 311                         print "<li>Checking tsearch2 permissions...";
 312                         ## Let's check all four, just to be safe
 313                         error_reporting( 0 );
 314                         $ts2tables = array('cfg','cfgmap','dict','parser');
 315                         foreach ( $ts2tables AS $tname ) {
 316                                 $SQL = "SELECT count(*) FROM $wgDBts2schema.pg_ts_$tname";
 317                                 $res = $this->doQuery($SQL);
 318                                 if (!$res) {
 319                                         print "<b>FAILED</b> to access pg_ts_$tname. Make sure that the user ".
 320                                         "\"$wgDBuser\" has SELECT access to all four tsearch2 tables</li>\n";
 321                                         dieout("</ul>");
 322                                 }
 323                         }
 324                         $SQL = "SELECT ts_name FROM $wgDBts2schema.pg_ts_cfg WHERE locale = '$ctype'";
 325                         $SQL .= " ORDER BY CASE WHEN ts_name <> 'default' THEN 1 ELSE 0 END";
 326                         $res = $this->doQuery($SQL);
 327                         error_reporting( E_ALL );
 328                         if (!$res) {
 329                                 print "<b>FAILED</b>. Could not determine the tsearch2 locale information</li>\n";
 330                                 dieout("</ul>");
 331                         }
 332                         print "OK</li>";
 333
 334                         ## Will the current locale work? Can we force it to?
 335                         print "<li>Verifying tsearch2 locale with $ctype...";
 336                         $rows = $this->numRows($res);
 337                         $resetlocale = 0;
 338                         if (!$rows) {
 339                                 print "<b>not found</b></li>\n";
 340                                 print "<li>Attempting to set default tsearch2 locale to \"$ctype\"...";
 341                                 $resetlocale = 1;
 342                         }
 343                         else {
 344                                 $tsname = pg_fetch_result($res, 0, 0);
 345                                 if ($tsname != 'default') {
 346                                         print "<b>not set to default ($tsname)</b>";
 347                                         print "<li>Attempting to change tsearch2 default locale to \"$ctype\"...";
 348                                         $resetlocale = 1;
 349                                 }
 350                         }
 351                         if ($resetlocale) {
 352                                 $SQL = "UPDATE $wgDBts2schema.pg_ts_cfg SET locale = '$ctype' WHERE ts_name = 'default'";
 353                                 $res = $this->doQuery($SQL);
 354                                 if (!$res) {
 355                                         print "<b>FAILED</b>. ";
 356                                         print "Please make sure that the locale in pg_ts_cfg for \"default\" is set to \"$ctype\"</li>\n";
 357                                         dieout("</ul>");
 358                                 }
 359                                 print "OK</li>";
 360                         }
 361
 362                         ## Final test: try out a simple tsearch2 query
 363                         $SQL = "SELECT $wgDBts2schema.to_tsvector('default','MediaWiki tsearch2 testing')";
 364                         $res = $this->doQuery($SQL);
 365                         if (!$res) {
 366                                 print "<b>FAILED</b>. Specifically, \"$SQL\" did not work.</li>";
 367                                 dieout("</ul>");
 368                         }
 369                         print "OK</li>";
 370
 371                         ## Do we have plpgsql installed?
 372                         print "<li>Checking for Pl/Pgsql ...";
 373                         $SQL = "SELECT 1 FROM pg_catalog.pg_language WHERE lanname = 'plpgsql'";
 374                         $rows = $this->numRows($this->doQuery($SQL));
 375                         if ($rows < 1) {
 376                                 // plpgsql is not installed, but if we have a pg_pltemplate table, we should be able to create it
 377                                 print "not installed. Attempting to install Pl/Pgsql ...";
 378                                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON (n.oid = c.relnamespace) ".
 379                                         "WHERE relname = 'pg_pltemplate' AND nspname='pg_catalog'";
 380                                 $rows = $this->numRows($this->doQuery($SQL));
 381                                 if ($rows >= 1) {
 382                                         $olde = error_reporting(0);
 383                                         error_reporting($olde - E_WARNING);
 384                                         $result = $this->doQuery("CREATE LANGUAGE plpgsql");
 385                                         error_reporting($olde);
 386                                         if (!$result) {
 387                                                 print "<b>FAILED</b>. You need to install the language plpgsql in the database <tt>$wgDBname</tt></li>";
 388                                                 dieout("</ul>");
 389                                         }
 390                                 }
 391                                 else {
 392                                         print "<b>FAILED</b>. You need to install the language plpgsql in the database <tt>$wgDBname</tt></li>";
 393                                         dieout("</ul>");
 394                                 }
 395                         }
 396                         print "OK</li>\n";
 397
 398                         ## Does the schema already exist? Who owns it?
 399                         $result = $this->schemaExists($wgDBmwschema);
 400                         if (!$result) {
 401                                 print "<li>Creating schema <b>$wgDBmwschema</b> ...";
 402                                 error_reporting( 0 );
 403                                 $result = $this->doQuery("CREATE SCHEMA $wgDBmwschema");
 404                                 error_reporting( E_ALL );
 405                                 if (!$result) {
 406                                         print "<b>FAILED</b>. The user \"$wgDBuser\" must be able to access the schema. ".
 407                                         "You can try making them the owner of the database, or try creating the schema with a ".
 408                                         "different user, and then grant access to the \"$wgDBuser\" user.</li>\n";
 409                                         dieout("</ul>");
 410                                 }
 411                                 print "OK</li>\n";
 412                         }
 413                         else if ($result != $user) {
 414                                 print "<li>Schema \"$wgDBmwschema\" exists but is not owned by \"$user\". Not ideal.</li>\n";
 415                         }
 416                         else {
 417                                 print "<li>Schema \"$wgDBmwschema\" exists and is owned by \"$user\". Excellent.</li>\n";
 418                         }
 419
 420                         ## Always return GMT time to accomodate the existing integer-based timestamp assumption
 421                         print "<li>Setting the timezone to GMT for user \"$user\" ...";
 422                         $SQL = "ALTER USER $safeuser SET timezone = 'GMT'";
 423                         $result = pg_query($this->mConn, $SQL);
 424                         if (!$result) {
 425                                 print "<b>FAILED</b>.</li>\n";
 426                                 dieout("</ul>");
 427                         }
 428                         print "OK</li>\n";
 429                         ## Set for the rest of this session
 430                         $SQL = "SET timezone = 'GMT'";
 431                         $result = pg_query($this->mConn, $SQL);
 432                         if (!$result) {
 433                                 print "<li>Failed to set timezone</li>\n";
 434                                 dieout("</ul>");
 435                         }
 436
 437                         print "<li>Setting the datestyle to ISO, YMD for user \"$user\" ...";
 438                         $SQL = "ALTER USER $safeuser SET datestyle = 'ISO, YMD'";
 439                         $result = pg_query($this->mConn, $SQL);
 440                         if (!$result) {
 441                                 print "<b>FAILED</b>.</li>\n";
 442                                 dieout("</ul>");
 443                         }
 444                         print "OK</li>\n";
 445                         ## Set for the rest of this session
 446                         $SQL = "SET datestyle = 'ISO, YMD'";
 447                         $result = pg_query($this->mConn, $SQL);
 448                         if (!$result) {
 449                                 print "<li>Failed to set datestyle</li>\n";
 450                                 dieout("</ul>");
 451                         }
 452
 453                         ## Fix up the search paths if needed
 454                         print "<li>Setting the search path for user \"$user\" ...";
 455                         $path = $this->quote_ident($wgDBmwschema);
 456                         if ($wgDBts2schema !== $wgDBmwschema)
 457                                 $path .= ", ". $this->quote_ident($wgDBts2schema);
 458                         if ($wgDBmwschema !== 'public' and $wgDBts2schema !== 'public')
 459                                 $path .= ", public";
 460                         $SQL = "ALTER USER $safeuser SET search_path = $path";
 461                         $result = pg_query($this->mConn, $SQL);
 462                         if (!$result) {
 463                                 print "<b>FAILED</b>.</li>\n";
 464                                 dieout("</ul>");
 465                         }
 466                         print "OK</li>\n";
 467                         ## Set for the rest of this session
 468                         $SQL = "SET search_path = $path";
 469                         $result = pg_query($this->mConn, $SQL);
 470                         if (!$result) {
 471                                 print "<li>Failed to set search_path</li>\n";
 472                                 dieout("</ul>");
 473                         }
 474                         define( "POSTGRES_SEARCHPATH", $path );
 475                 }}
 476
 477                 global $wgCommandLineMode;
 478                 ## If called from the command-line (e.g. importDump), only show errors
 479                 if ($wgCommandLineMode) {
 480                         $this->doQuery("SET client_min_messages = 'ERROR'");
 481                 }
 482
 483                 return $this->mConn;
 484         }
 485
 486         /**
 487          * Closes a database connection, if it is open
 488          * Returns success, true if already closed
 489          */
 490         function close() {
 491                 $this->mOpened = false;
 492                 if ( $this->mConn ) {
 493                         return pg_close( $this->mConn );
 494                 } else {
 495                         return true;
 496                 }
 497         }
 498
 499         function doQuery( $sql ) {
 500                 return $this->mLastResult=pg_query( $this->mConn , $sql);
 501         }
 502
 503         function queryIgnore( $sql, $fname = '' ) {
 504                 return $this->query( $sql, $fname, true );
 505         }
 506
 507         function freeResult( $res ) {
 508                 if ( $res instanceof ResultWrapper ) {
 509                         $res = $res->result;
 510                 }
 511                 if ( !@pg_free_result( $res ) ) {
 512                         throw new DBUnexpectedError($this,  "Unable to free Postgres result\n" );
 513                 }
 514         }
 515
 516         function fetchObject( $res ) {
 517                 if ( $res instanceof ResultWrapper ) {
 518                         $res = $res->result;
 519                 }
 520                 @$row = pg_fetch_object( $res );
 521                 # FIXME: HACK HACK HACK HACK debug
 522
 523                 # TODO:
 524                 # hashar : not sure if the following test really trigger if the object
 525                 #          fetching failed.
 526                 if( pg_last_error($this->mConn) ) {
 527                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 528                 }
 529                 return $row;
 530         }
 531
 532         function fetchRow( $res ) {
 533                 if ( $res instanceof ResultWrapper ) {
 534                         $res = $res->result;
 535                 }
 536                 @$row = pg_fetch_array( $res );
 537                 if( pg_last_error($this->mConn) ) {
 538                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 539                 }
 540                 return $row;
 541         }
 542
 543         function numRows( $res ) {
 544                 if ( $res instanceof ResultWrapper ) {
 545                         $res = $res->result;
 546                 }
 547                 @$n = pg_num_rows( $res );
 548                 if( pg_last_error($this->mConn) ) {
 549                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 550                 }
 551                 return $n;
 552         }
 553         function numFields( $res ) {
 554                 if ( $res instanceof ResultWrapper ) {
 555                         $res = $res->result;
 556                 }
 557                 return pg_num_fields( $res );
 558         }
 559         function fieldName( $res, $n ) {
 560                 if ( $res instanceof ResultWrapper ) {
 561                         $res = $res->result;
 562                 }
 563                 return pg_field_name( $res, $n );
 564         }
 565
 566         /**
 567          * This must be called after nextSequenceVal
 568          */
 569         function insertId() {
 570                 return $this->mInsertId;
 571         }
 572
 573         function dataSeek( $res, $row ) {
 574                 if ( $res instanceof ResultWrapper ) {
 575                         $res = $res->result;
 576                 }
 577                 return pg_result_seek( $res, $row );
 578         }
 579
 580         function lastError() {
 581                 if ( $this->mConn ) {
 582                         return pg_last_error();
 583                 }
 584                 else {
 585                         return "No database connection";
 586                 }
 587         }
 588         function lastErrno() {
 589                 return pg_last_error() ? 1 : 0;
 590         }
 591
 592         function affectedRows() {
 593                 if( !isset( $this->mLastResult ) or ! $this->mLastResult )
 594                         return 0;
 595
 596                 return pg_affected_rows( $this->mLastResult );
 597         }
 598
 599         /**
 600          * Estimate rows in dataset
 601          * Returns estimated count, based on EXPLAIN output
 602          * This is not necessarily an accurate estimate, so use sparingly
 603          * Returns -1 if count cannot be found
 604          * Takes same arguments as Database::select()
 605          */
 606
 607         function estimateRowCount( $table, $vars='*', $conds='', $fname = 'Database::estimateRowCount', $options = array() ) {
 608                 $options['EXPLAIN'] = true;
 609                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 610                 $rows = -1;
 611                 if ( $res ) {
 612                         $row = $this->fetchRow( $res );
 613                         $count = array();
 614                         if( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
 615                                 $rows = $count[1];
 616                         }
 617                         $this->freeResult($res);
 618                 }
 619                 return $rows;
 620         }
 621
 622
 623         /**
 624          * Returns information about an index
 625          * If errors are explicitly ignored, returns NULL on failure
 626          */
 627         function indexInfo( $table, $index, $fname = 'Database::indexExists' ) {
 628                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 629                 $res = $this->query( $sql, $fname );
 630                 if ( !$res ) {
 631                         return NULL;
 632                 }
 633                 while ( $row = $this->fetchObject( $res ) ) {
 634                         if ( $row->indexname == $index ) {
 635                                 return $row;
 636                         }
 637                 }
 638                 return false;
 639         }
 640
 641         function indexUnique ($table, $index, $fname = 'Database::indexUnique' ) {
 642                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 643                         " AND indexdef LIKE 'CREATE UNIQUE%({$index})'";
 644                 $res = $this->query( $sql, $fname );
 645                 if ( !$res )
 646                         return NULL;
 647                 while ($row = $this->fetchObject( $res ))
 648                         return true;
 649                 return false;
 650
 651         }
 652
 653         /**
 654          * INSERT wrapper, inserts an array into a table
 655          *
 656          * $args may be a single associative array, or an array of these with numeric keys,
 657          * for multi-row insert (Postgres version 8.2 and above only).
 658          *
 659          * @param array $table   String: Name of the table to insert to.
 660          * @param array $args    Array: Items to insert into the table.
 661          * @param array $fname   String: Name of the function, for profiling
 662          * @param mixed $options String or Array. Valid options: IGNORE
 663          *
 664          * @return bool Success of insert operation. IGNORE always returns true.
 665          */
 666         function insert( $table, $args, $fname = 'DatabasePostgres::insert', $options = array() ) {
 667                 global $wgDBversion;
 668
 669                 $table = $this->tableName( $table );
 670                 if (! isset( $wgDBversion ) ) {
 671                         $this->getServerVersion();
 672                         $wgDBversion = $this->numeric_version;
 673                 }
 674
 675                 if ( !is_array( $options ) )
 676                         $options = array( $options );
 677
 678                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 679                         $multi = true;
 680                         $keys = array_keys( $args[0] );
 681                 }
 682                 else {
 683                         $multi = false;
 684                         $keys = array_keys( $args );
 685                 }
 686
 687                 $ignore = in_array( 'IGNORE', $options ) ? 1 : 0;
 688                 if ( $ignore )
 689                         $olde = error_reporting( 0 );
 690
 691                 $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 692
 693                 if ( $multi ) {
 694                         if ( $wgDBversion >= 8.1 ) {
 695                                 $first = true;
 696                                 foreach ( $args as $row ) {
 697                                         if ( $first ) {
 698                                                 $first = false;
 699                                         } else {
 700                                                 $sql .= ',';
 701                                         }
 702                                         $sql .= '(' . $this->makeList( $row ) . ')';
 703                                 }
 704                                 $res = (bool)$this->query( $sql, $fname, $ignore );
 705                         }
 706                         else {
 707                                 $res = true;
 708                                 $origsql = $sql;
 709                                 foreach ( $args as $row ) {
 710                                         $tempsql = $origsql;
 711                                         $tempsql .= '(' . $this->makeList( $row ) . ')';
 712                                         $tempres = (bool)$this->query( $tempsql, $fname, $ignore );
 713                                         if (! $tempres)
 714                                                 $res = false;
 715                                 }
 716                         }
 717                 }
 718                 else {
 719                         $sql .= '(' . $this->makeList( $args ) . ')';
 720                         $res = (bool)$this->query( $sql, $fname, $ignore );
 721                 }
 722
 723                 if ( $ignore ) {
 724                         $olde = error_reporting( $olde );
 725                         return true;
 726                 }
 727
 728                 return $res;
 729
 730         }
 731
 732         function tableName( $name ) {
 733                 # Replace reserved words with better ones
 734                 switch( $name ) {
 735                         case 'user':
 736                                 return 'mwuser';
 737                         case 'text':
 738                                 return 'pagecontent';
 739                         default:
 740                                 return $name;
 741                 }
 742         }
 743
 744         /**
 745          * Return the next in a sequence, save the value for retrieval via insertId()
 746          */
 747         function nextSequenceValue( $seqName ) {
 748                 $safeseq = preg_replace( "/'/", "''", $seqName );
 749                 $res = $this->query( "SELECT nextval('$safeseq')" );
 750                 $row = $this->fetchRow( $res );
 751                 $this->mInsertId = $row[0];
 752                 $this->freeResult( $res );
 753                 return $this->mInsertId;
 754         }
 755
 756         /**
 757          * Postgres does not have a "USE INDEX" clause, so return an empty string
 758          */
 759         function useIndexClause( $index ) {
 760                 return '';
 761         }
 762
 763         # REPLACE query wrapper
 764         # Postgres simulates this with a DELETE followed by INSERT
 765         # $row is the row to insert, an associative array
 766         # $uniqueIndexes is an array of indexes. Each element may be either a
 767         # field name or an array of field names
 768         #
 769         # It may be more efficient to leave off unique indexes which are unlikely to collide.
 770         # However if you do this, you run the risk of encountering errors which wouldn't have
 771         # occurred in MySQL
 772         function replace( $table, $uniqueIndexes, $rows, $fname = 'Database::replace' ) {
 773                 $table = $this->tableName( $table );
 774
 775                 if (count($rows)==0) {
 776                         return;
 777                 }
 778
 779                 # Single row case
 780                 if ( !is_array( reset( $rows ) ) ) {
 781                         $rows = array( $rows );
 782                 }
 783
 784                 foreach( $rows as $row ) {
 785                         # Delete rows which collide
 786                         if ( $uniqueIndexes ) {
 787                                 $sql = "DELETE FROM $table WHERE ";
 788                                 $first = true;
 789                                 foreach ( $uniqueIndexes as $index ) {
 790                                         if ( $first ) {
 791                                                 $first = false;
 792                                                 $sql .= "(";
 793                                         } else {
 794                                                 $sql .= ') OR (';
 795                                         }
 796                                         if ( is_array( $index ) ) {
 797                                                 $first2 = true;
 798                                                 foreach ( $index as $col ) {
 799                                                         if ( $first2 ) {
 800                                                                 $first2 = false;
 801                                                         } else {
 802                                                                 $sql .= ' AND ';
 803                                                         }
 804                                                         $sql .= $col.'=' . $this->addQuotes( $row[$col] );
 805                                                 }
 806                                         } else {
 807                                                 $sql .= $index.'=' . $this->addQuotes( $row[$index] );
 808                                         }
 809                                 }
 810                                 $sql .= ')';
 811                                 $this->query( $sql, $fname );
 812                         }
 813
 814                         # Now insert the row
 815                         $sql = "INSERT INTO $table (" . $this->makeList( array_keys( $row ), LIST_NAMES ) .') VALUES (' .
 816                                 $this->makeList( $row, LIST_COMMA ) . ')';
 817                         $this->query( $sql, $fname );
 818                 }
 819         }
 820
 821         # DELETE where the condition is a join
 822         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = "Database::deleteJoin" ) {
 823                 if ( !$conds ) {
 824                         throw new DBUnexpectedError($this,  'Database::deleteJoin() called with empty $conds' );
 825                 }
 826
 827                 $delTable = $this->tableName( $delTable );
 828                 $joinTable = $this->tableName( $joinTable );
 829                 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
 830                 if ( $conds != '*' ) {
 831                         $sql .= 'WHERE ' . $this->makeList( $conds, LIST_AND );
 832                 }
 833                 $sql .= ')';
 834
 835                 $this->query( $sql, $fname );
 836         }
 837
 838         # Returns the size of a text field, or -1 for "unlimited"
 839         function textFieldSize( $table, $field ) {
 840                 $table = $this->tableName( $table );
 841                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
 842                         FROM pg_class c, pg_attribute a, pg_type t
 843                         WHERE relname='$table' AND a.attrelid=c.oid AND
 844                                 a.atttypid=t.oid and a.attname='$field'";
 845                 $res =$this->query($sql);
 846                 $row=$this->fetchObject($res);
 847                 if ($row->ftype=="varchar") {
 848                         $size=$row->size-4;
 849                 } else {
 850                         $size=$row->size;
 851                 }
 852                 $this->freeResult( $res );
 853                 return $size;
 854         }
 855
 856         function lowPriorityOption() {
 857                 return '';
 858         }
 859
 860         function limitResult($sql, $limit,$offset=false) {
 861                 return "$sql LIMIT $limit ".(is_numeric($offset)?" OFFSET {$offset} ":"");
 862         }
 863
 864         /**
 865          * Returns an SQL expression for a simple conditional.
 866          * Uses CASE on Postgres
 867          *
 868          * @param string $cond SQL expression which will result in a boolean value
 869          * @param string $trueVal SQL expression to return if true
 870          * @param string $falseVal SQL expression to return if false
 871          * @return string SQL fragment
 872          */
 873         function conditional( $cond, $trueVal, $falseVal ) {
 874                 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
 875         }
 876
 877         function wasDeadlock() {
 878                 return $this->lastErrno() == '40P01';
 879         }
 880
 881         function timestamp( $ts=0 ) {
 882                 return wfTimestamp(TS_POSTGRES,$ts);
 883         }
 884
 885         /**
 886          * Return aggregated value function call
 887          */
 888         function aggregateValue ($valuedata,$valuename='value') {
 889                 return $valuedata;
 890         }
 891
 892
 893         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 894                 # Ignore errors during error handling to avoid infinite recursion
 895                 $ignore = $this->ignoreErrors( true );
 896                 ++$this->mErrorCount;
 897
 898                 if ($ignore || $tempIgnore) {
 899                         wfDebug("SQL ERROR (ignored): $error\n");
 900                         $this->ignoreErrors( $ignore );
 901                 }
 902                 else {
 903                         $message = "A database error has occurred\n" .
 904                                 "Query: $sql\n" .
 905                                 "Function: $fname\n" .
 906                                 "Error: $errno $error\n";
 907                         throw new DBUnexpectedError($this, $message);
 908                 }
 909         }
 910
 911         /**
 912          * @return string wikitext of a link to the server software's web site
 913          */
 914         function getSoftwareLink() {
 915                 return "[http://www.postgresql.org/ PostgreSQL]";
 916         }
 917
 918         /**
 919          * @return string Version information from the database
 920          */
 921         function getServerVersion() {
 922                 $version = pg_fetch_result($this->doQuery("SELECT version()"),0,0);
 923                 $thisver = array();
 924                 if (!preg_match('/PostgreSQL (\d+\.\d+)(\S+)/', $version, $thisver)) {
 925                         die("Could not determine the numeric version from $version!");
 926                 }
 927                 $this->numeric_version = $thisver[1];
 928                 return $version;
 929         }
 930
 931
 932         /**
 933          * Query whether a given relation exists (in the given schema, or the
 934          * default mw one if not given)
 935          */
 936         function relationExists( $table, $types, $schema = false ) {
 937                 global $wgDBmwschema;
 938                 if (!is_array($types))
 939                         $types = array($types);
 940                 if (! $schema )
 941                         $schema = $wgDBmwschema;
 942                 $etable = $this->addQuotes($table);
 943                 $eschema = $this->addQuotes($schema);
 944                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
 945                         . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
 946                         . "AND c.relkind IN ('" . implode("','", $types) . "')";
 947                 $res = $this->query( $SQL );
 948                 $count = $res ? $res->numRows() : 0;
 949                 if ($res)
 950                         $this->freeResult( $res );
 951                 return $count ? true : false;
 952         }
 953
 954         /*
 955          * For backward compatibility, this function checks both tables and
 956          * views.
 957          */
 958         function tableExists ($table, $schema = false) {
 959                 return $this->relationExists($table, array('r', 'v'), $schema);
 960         }
 961
 962         function sequenceExists ($sequence, $schema = false) {
 963                 return $this->relationExists($sequence, 'S', $schema);
 964         }
 965
 966         function triggerExists($table, $trigger) {
 967                 global $wgDBmwschema;
 968
 969                 $q = <<<END
 970         SELECT 1 FROM pg_class, pg_namespace, pg_trigger
 971                 WHERE relnamespace=pg_namespace.oid AND relkind='r'
 972                       AND tgrelid=pg_class.oid
 973                       AND nspname=%s AND relname=%s AND tgname=%s
 974 END;
 975                 $res = $this->query(sprintf($q,
 976                                 $this->addQuotes($wgDBmwschema),
 977                                 $this->addQuotes($table),
 978                                 $this->addQuotes($trigger)));
 979                 if (!$res)
 980                         return NULL;
 981                 $rows = $res->numRows();
 982                 $this->freeResult($res);
 983                 return $rows;
 984         }
 985
 986         function ruleExists($table, $rule) {
 987                 global $wgDBmwschema;
 988                 $exists = $this->selectField("pg_rules", "rulename",
 989                                 array(  "rulename" => $rule,
 990                                         "tablename" => $table,
 991                                         "schemaname" => $wgDBmwschema));
 992                 return $exists === $rule;
 993         }
 994
 995         function constraintExists($table, $constraint) {
 996                 global $wgDBmwschema;
 997                 $SQL = sprintf("SELECT 1 FROM information_schema.table_constraints ".
 998                            "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
 999                         $this->addQuotes($wgDBmwschema),
1000                         $this->addQuotes($table),
1001                         $this->addQuotes($constraint));
1002                 $res = $this->query($SQL);
1003                 if (!$res)
1004                         return NULL;
1005                 $rows = $res->numRows();
1006                 $this->freeResult($res);
1007                 return $rows;
1008         }
1009
1010         /**
1011          * Query whether a given schema exists. Returns the name of the owner
1012          */
1013         function schemaExists( $schema ) {
1014                 $eschema = preg_replace("/'/", "''", $schema);
1015                 $SQL = "SELECT rolname FROM pg_catalog.pg_namespace n, pg_catalog.pg_roles r "
1016                                 ."WHERE n.nspowner=r.oid AND n.nspname = '$eschema'";
1017                 $res = $this->query( $SQL );
1018                 if ( $res && $res->numRows() ) {
1019                         $row = $res->fetchRow();
1020                         $owner = $row->rolname;
1021                 } else {
1022                         $owner = false;
1023                 }
1024                 if ($res)
1025                         $this->freeResult($res);
1026                 return $owner;
1027         }
1028
1029         /**
1030          * Query whether a given column exists in the mediawiki schema
1031          */
1032         function fieldExists( $table, $field, $fname = 'DatabasePostgres::fieldExists' ) {
1033                 global $wgDBmwschema;
1034                 $etable = preg_replace("/'/", "''", $table);
1035                 $eschema = preg_replace("/'/", "''", $wgDBmwschema);
1036                 $ecol = preg_replace("/'/", "''", $field);
1037                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n, pg_catalog.pg_attribute a "
1038                         . "WHERE c.relnamespace = n.oid AND c.relname = '$etable' AND n.nspname = '$eschema' "
1039                         . "AND a.attrelid = c.oid AND a.attname = '$ecol'";
1040                 $res = $this->query( $SQL, $fname );
1041                 $count = $res ? $res->numRows() : 0;
1042                 if ($res)
1043                         $this->freeResult( $res );
1044                 return $count;
1045         }
1046
1047         function fieldInfo( $table, $field ) {
1048                 return PostgresField::fromText($this, $table, $field);
1049         }
1050
1051         function begin( $fname = 'DatabasePostgres::begin' ) {
1052                 $this->query( 'BEGIN', $fname );
1053                 $this->mTrxLevel = 1;
1054         }
1055         function immediateCommit( $fname = 'DatabasePostgres::immediateCommit' ) {
1056                 return true;
1057         }
1058         function commit( $fname = 'DatabasePostgres::commit' ) {
1059                 $this->query( 'COMMIT', $fname );
1060                 $this->mTrxLevel = 0;
1061         }
1062
1063         /* Not even sure why this is used in the main codebase... */
1064         function limitResultForUpdate($sql, $num) {
1065                 return $sql;
1066         }
1067
1068         function setup_database() {
1069                 global $wgVersion, $wgDBmwschema, $wgDBts2schema, $wgDBport, $wgDBuser;
1070
1071                 ## Make sure that we can write to the correct schema
1072                 ## If not, Postgres will happily and silently go to the next search_path item
1073                 $ctest = "mw_test_table";
1074                 if ($this->tableExists($ctest, $wgDBmwschema)) {
1075                         $this->doQuery("DROP TABLE $wgDBmwschema.$ctest");
1076                 }
1077                 $SQL = "CREATE TABLE $wgDBmwschema.$ctest(a int)";
1078                 $olde = error_reporting( 0 );
1079                 $res = $this->doQuery($SQL);
1080                 error_reporting( $olde );
1081                 if (!$res) {
1082                         print "<b>FAILED</b>. Make sure that the user \"$wgDBuser\" can write to the schema \"$wgDBmwschema\"</li>\n";
1083                         dieout("</ul>");
1084                 }
1085                 $this->doQuery("DROP TABLE $wgDBmwschema.mw_test_table");
1086
1087                 dbsource( "../maintenance/postgres/tables.sql", $this);
1088
1089                 ## Version-specific stuff
1090                 if ($this->numeric_version == 8.1) {
1091                         $this->doQuery("CREATE INDEX ts2_page_text ON pagecontent USING gist(textvector)");
1092                         $this->doQuery("CREATE INDEX ts2_page_title ON page USING gist(titlevector)");
1093                 }
1094                 else {
1095                         $this->doQuery("CREATE INDEX ts2_page_text ON pagecontent USING gin(textvector)");
1096                         $this->doQuery("CREATE INDEX ts2_page_title ON page USING gin(titlevector)");
1097                 }
1098
1099                 ## Update version information
1100                 $mwv = $this->addQuotes($wgVersion);
1101                 $pgv = $this->addQuotes($this->getServerVersion());
1102                 $pgu = $this->addQuotes($this->mUser);
1103                 $mws = $this->addQuotes($wgDBmwschema);
1104                 $tss = $this->addQuotes($wgDBts2schema);
1105                 $pgp = $this->addQuotes($wgDBport);
1106                 $dbn = $this->addQuotes($this->mDBname);
1107                 $ctypeRow = $this->doQuery("SHOW lc_ctype")->fetchArray();
1108                 $ctype = $ctypeRow[0];
1109
1110                 $SQL = "UPDATE mediawiki_version SET mw_version=$mwv, pg_version=$pgv, pg_user=$pgu, ".
1111                                 "mw_schema = $mws, ts2_schema = $tss, pg_port=$pgp, pg_dbname=$dbn, ".
1112                                 "ctype = '$ctype' ".
1113                                 "WHERE type = 'Creation'";
1114                 $this->query($SQL);
1115
1116                 ## Avoid the non-standard "REPLACE INTO" syntax
1117                 $f = fopen( "../maintenance/interwiki.sql", 'r' );
1118                 if ($f == false ) {
1119                         dieout( "<li>Could not find the interwiki.sql file");
1120                 }
1121                 ## We simply assume it is already empty as we have just created it
1122                 $SQL = "INSERT INTO interwiki(iw_prefix,iw_url,iw_local) VALUES ";
1123                 while ( ! feof( $f ) ) {
1124                         $line = fgets($f,1024);
1125                         $matches = array();
1126                         if (!preg_match('/^\s*(\(.+?),(\d)\)/', $line, $matches)) {
1127                                 continue;
1128                         }
1129                         $this->query("$SQL $matches[1],$matches[2])");
1130                 }
1131                 print " (table interwiki successfully populated)...\n";
1132
1133                 $this->doQuery("COMMIT");
1134         }
1135
1136         function encodeBlob( $b ) {
1137                 return pg_escape_bytea( $b );
1138         }
1139         function decodeBlob( $b ) {
1140                 return pg_unescape_bytea( $b );
1141         }
1142
1143         function strencode( $s ) { ## Should not be called by us
1144                 return pg_escape_string( $s );
1145         }
1146
1147         function addQuotes( $s ) {
1148                 if ( is_null( $s ) ) {
1149                         return 'NULL';
1150                 } else if (is_array( $s )) { ## Assume it is bytea data
1151                         return "E'$s[1]'";
1152                 }
1153                 return "'" . pg_escape_string($s) . "'";
1154                 // Unreachable: return "E'" . pg_escape_string($s) . "'";
1155         }
1156
1157         function quote_ident( $s ) {
1158                 return '"' . preg_replace( '/"/', '""', $s) . '"';
1159         }
1160
1161         /* For now, does nothing */
1162         function selectDB( $db ) {
1163                 return true;
1164         }
1165
1166         /**
1167          * Various select options
1168          *
1169          * @private
1170          *
1171          * @param array $options an associative array of options to be turned into
1172          *              an SQL query, valid keys are listed in the function.
1173          * @return array
1174          */
1175         function makeSelectOptions( $options ) {
1176                 $preLimitTail = $postLimitTail = '';
1177                 $startOpts = $useIndex = '';
1178
1179                 $noKeyOptions = array();
1180                 foreach ( $options as $key => $option ) {
1181                         if ( is_numeric( $key ) ) {
1182                                 $noKeyOptions[$option] = true;
1183                         }
1184                 }
1185
1186                 if ( isset( $options['GROUP BY'] ) ) $preLimitTail .= " GROUP BY " . $options['GROUP BY'];
1187                 if ( isset( $options['HAVING'] ) ) $preLimitTail .= " HAVING {$options['HAVING']}";
1188                 if ( isset( $options['ORDER BY'] ) ) $preLimitTail .= " ORDER BY " . $options['ORDER BY'];
1189
1190                 //if (isset($options['LIMIT'])) {
1191                 //      $tailOpts .= $this->limitResult('', $options['LIMIT'],
1192                 //              isset($options['OFFSET']) ? $options['OFFSET']
1193                 //              : false);
1194                 //}
1195
1196                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) $postLimitTail .= ' FOR UPDATE';
1197                 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) $postLimitTail .= ' LOCK IN SHARE MODE';
1198                 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) $startOpts .= 'DISTINCT';
1199
1200                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1201         }
1202
1203         public function setTimeout( $timeout ) {
1204                 // @todo fixme no-op
1205         }
1206
1207         function ping() {
1208                 wfDebug( "Function ping() not written for DatabasePostgres.php yet");
1209                 return true;
1210         }
1211
1212         /**
1213          * How lagged is this slave?
1214          *
1215          */
1216         public function getLag() {
1217                 # Not implemented for PostgreSQL
1218                 return false;
1219         }
1220
1221 } // end DatabasePostgres class
1222
1223