includes/DatabasePostgres.php

   1 <?php
   2
   3 /**
   4  * This is 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  * @package MediaWiki
  11  */
  12
  13 class DatabasePostgres extends Database {
  14         var $mInsertId = NULL;
  15         var $mLastResult = NULL;
  16
  17         function DatabasePostgres($server = false, $user = false, $password = false, $dbName = false,
  18                 $failFunction = false, $flags = 0 )
  19         {
  20
  21                 global $wgOut;
  22                 # Can't get a reference if it hasn't been set yet
  23                 if ( !isset( $wgOut ) ) {
  24                         $wgOut = NULL;
  25                 }
  26                 $this->mOut =& $wgOut;
  27                 $this->mFailFunction = $failFunction;
  28                 $this->mCascadingDeletes = true;
  29                 $this->mCleanupTriggers = true;
  30                 $this->mStrictIPs = true;
  31                 $this->mRealTimestamps = true;
  32                 $this->mFlags = $flags;
  33                 $this->open( $server, $user, $password, $dbName);
  34
  35         }
  36
  37         static function newFromParams( $server = false, $user = false, $password = false, $dbName = false,
  38                 $failFunction = false, $flags = 0)
  39         {
  40                 return new DatabasePostgres( $server, $user, $password, $dbName, $failFunction, $flags );
  41         }
  42
  43         /**
  44          * Usually aborts on failure
  45          * If the failFunction is set to a non-zero integer, returns success
  46          */
  47         function open( $server, $user, $password, $dbName ) {
  48                 # Test for Postgres support, to avoid suppressed fatal error
  49                 if ( !function_exists( 'pg_connect' ) ) {
  50                         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" );
  51                 }
  52
  53
  54                 global $wgDBport;
  55
  56                 $this->close();
  57                 $this->mServer = $server;
  58                 $port = $wgDBport;
  59                 $this->mUser = $user;
  60                 $this->mPassword = $password;
  61                 $this->mDBname = $dbName;
  62
  63                 $hstring="";
  64                 if ($server!=false && $server!="") {
  65                         $hstring="host=$server ";
  66                 }
  67                 if ($port!=false && $port!="") {
  68                         $hstring .= "port=$port ";
  69                 }
  70
  71                 if (!strlen($user)) { ## e.g. the class is being loaded
  72                         return;
  73                 }
  74
  75                 error_reporting( E_ALL );
  76                 @$this->mConn = pg_connect("$hstring dbname=$dbName user=$user password=$password");
  77
  78                 if ( $this->mConn == false ) {
  79                         wfDebug( "DB connection error\n" );
  80                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
  81                         wfDebug( $this->lastError()."\n" );
  82                         return false;
  83                 }
  84
  85                 $this->mOpened = true;
  86                 ## If this is the initial connection, setup the schema stuff and possibly create the user
  87                 if (defined('MEDIAWIKI_INSTALL')) {
  88                         global $wgDBname, $wgDBuser, $wgDBpassword, $wgDBsuperuser, $wgDBmwschema,
  89                                 $wgDBts2schema;
  90                         print "OK</li>\n";
  91
  92                         print "<li>Checking the version of Postgres...";
  93                         $version = pg_fetch_result($this->doQuery("SELECT version()"),0,0);
  94                         $thisver = array();
  95                         if (!preg_match('/PostgreSQL (\d+\.\d+)(\S+)/', $version, $thisver)) {
  96                                 print "<b>FAILED</b> (could not determine the version)</li>\n";
  97                                 dieout("</ul>");
  98                         }
  99                         $PGMINVER = "8.1";
 100                         if ($thisver[1] < $PGMINVER) {
 101                                 print "<b>FAILED</b>. Required version is $PGMINVER. You have $thisver[1]$thisver[2]</li>\n";
 102                                 dieout("</ul>");
 103                         }
 104                         print "version $thisver[1]$thisver[2] is OK.</li>\n";
 105
 106                         $safeuser = $this->quote_ident($wgDBuser);
 107                         ## Are we connecting as a superuser for the first time?
 108                         if ($wgDBsuperuser) {
 109                                 ## Are we really a superuser? Check out our rights
 110                                 $SQL = "SELECT
 111                                                 CASE WHEN usesuper IS TRUE THEN
 112                                                         CASE WHEN usecreatedb IS TRUE THEN 3 ELSE 1 END
 113                                                         ELSE CASE WHEN usecreatedb IS TRUE THEN 2 ELSE 0 END
 114                         END AS rights
 115                                                 FROM pg_catalog.pg_user WHERE usename = " . $this->addQuotes($wgDBsuperuser);
 116                                 $rows = $this->numRows($res = $this->doQuery($SQL));
 117                                 if (!$rows) {
 118                                         print "<li>ERROR: Could not read permissions for user \"$wgDBsuperuser\"</li>\n";
 119                                         dieout('</ul>');
 120                                 }
 121                                 $perms = pg_fetch_result($res, 0, 0);
 122
 123                                 $SQL = "SELECT 1 FROM pg_catalog.pg_user WHERE usename = " . $this->addQuotes($wgDBuser);
 124                                 $rows = $this->numRows($this->doQuery($SQL));
 125                                 if ($rows) {
 126                                         print "<li>User \"$wgDBuser\" already exists, skipping account creation.</li>";
 127                                 }
 128                                 else {
 129                                         if ($perms != 1 and $perms != 3) {
 130                                                 print "<li>ERROR: the user \"$wgDBsuperuser\" cannot create other users. ";
 131                                                 print 'Please use a different Postgres user.</li>';
 132                                                 dieout('</ul>');
 133                                         }
 134                                         print "<li>Creating user <b>$wgDBuser</b>...";
 135                                         $safepass = $this->addQuotes($wgDBpassword);
 136                                         $SQL = "CREATE USER $safeuser NOCREATEDB PASSWORD $safepass";
 137                                         $this->doQuery($SQL);
 138                                         print "OK</li>\n";
 139                                 }
 140                                 ## User now exists, check out the database
 141                                 if ($dbName != $wgDBname) {
 142                                         $SQL = "SELECT 1 FROM pg_catalog.pg_database WHERE datname = " . $this->addQuotes($wgDBname);
 143                                         $rows = $this->numRows($this->doQuery($SQL));
 144                                         if ($rows) {
 145                                                 print "<li>Database \"$wgDBname\" already exists, skipping database creation.</li>";
 146                                         }
 147                                         else {
 148                                                 if ($perms < 2) {
 149                                                         print "<li>ERROR: the user \"$wgDBsuperuser\" cannot create databases. ";
 150                                                         print 'Please use a different Postgres user.</li>';
 151                                                         dieout('</ul>');
 152                                                 }
 153                                                 print "<li>Creating database <b>$wgDBname</b>...";
 154                                                 $safename = $this->quote_ident($wgDBname);
 155                                                 $SQL = "CREATE DATABASE $safename OWNER $safeuser ";
 156                                                 $this->doQuery($SQL);
 157                                                 print "OK</li>\n";
 158                                                 ## Hopefully tsearch2 and plpgsql are in template1...
 159                                         }
 160
 161                                         ## Reconnect to check out tsearch2 rights for this user
 162                                         print "<li>Connecting to \"$wgDBname\" as superuser \"$wgDBsuperuser\" to check rights...";
 163                                         @$this->mConn = pg_connect("$hstring dbname=$wgDBname user=$user password=$password");
 164                                         if ( $this->mConn == false ) {
 165                                                 print "<b>FAILED TO CONNECT!</b></li>";
 166                                                 dieout("</ul>");
 167                                         }
 168                                         print "OK</li>\n";
 169                                 }
 170
 171                                 ## Tsearch2 checks
 172                                 print "<li>Checking that tsearch2 is installed in the database \"$wgDBname\"...";
 173                                 if (! $this->tableExists("pg_ts_cfg", $wgDBts2schema)) {
 174                                         print "<b>FAILED</b>. tsearch2 must be installed in the database \"$wgDBname\".";
 175                                         print "Please see <a href='http://www.devx.com/opensource/Article/21674/0/page/2'>this article</a>";
 176                                         print " for instructions or ask on #postgresql on irc.freenode.net</li>\n";
 177                                         dieout("</ul>");
 178                                 }
 179                                 print "OK</li>\n";
 180                                 print "<li>Ensuring that user \"$wgDBuser\" has select rights on the tsearch2 tables...";
 181                                 foreach (array('cfg','cfgmap','dict','parser') as $table) {
 182                                         $SQL = "GRANT SELECT ON pg_ts_$table TO $safeuser";
 183                                         $this->doQuery($SQL);
 184                                 }
 185                                 print "OK</li>\n";
 186
 187
 188                                 ## Setup the schema for this user if needed
 189                                 $result = $this->schemaExists($wgDBmwschema);
 190                                 $safeschema = $this->quote_ident($wgDBmwschema);
 191                                 if (!$result) {
 192                                         print "<li>Creating schema <b>$wgDBmwschema</b> ...";
 193                                         $result = $this->doQuery("CREATE SCHEMA $safeschema AUTHORIZATION $safeuser");
 194                                         if (!$result) {
 195                                                 print "<b>FAILED</b>.</li>\n";
 196                                                 dieout("</ul>");
 197                                         }
 198                                         print "OK</li>\n";
 199                                 }
 200                                 else {
 201                                         print "<li>Schema already exists, explicitly granting rights...\n";
 202                                         $safeschema2 = $this->addQuotes($wgDBmwschema);
 203                                         $SQL = "SELECT 'GRANT ALL ON '||pg_catalog.quote_ident(relname)||' TO $safeuser;'\n".
 204                                                         "FROM pg_catalog.pg_class p, pg_catalog.pg_namespace n\n".
 205                                                         "WHERE relnamespace = n.oid AND n.nspname = $safeschema2\n".
 206                                                         "AND p.relkind IN ('r','S','v')\n";
 207                                         $SQL .= "UNION\n";
 208                                         $SQL .= "SELECT 'GRANT ALL ON FUNCTION '||pg_catalog.quote_ident(proname)||'('||\n".
 209                                                         "pg_catalog.oidvectortypes(p.proargtypes)||') TO $safeuser;'\n".
 210                                                         "FROM pg_catalog.pg_proc p, pg_catalog.pg_namespace n\n".
 211                                                         "WHERE p.pronamespace = n.oid AND n.nspname = $safeschema2";
 212                                         $res = $this->doQuery($SQL);
 213                                         if (!$res) {
 214                                                 print "<b>FAILED</b>. Could not set rights for the user.</li>\n";
 215                                                 dieout("</ul>");
 216                                         }
 217                                         $this->doQuery("SET search_path = $safeschema");
 218                                         $rows = $this->numRows($res);
 219                                         while ($rows) {
 220                                                 $rows--;
 221                                                 $this->doQuery(pg_fetch_result($res, $rows, 0));
 222                                         }
 223                                         print "OK</li>";
 224                                 }
 225
 226                                 $wgDBsuperuser = '';
 227                                 return true; ## Reconnect as regular user
 228                         }
 229
 230                 if (!defined('POSTGRES_SEARCHPATH')) {
 231
 232                         ## Do we have the basic tsearch2 table?
 233                         print "<li>Checking for tsearch2 in the schema \"$wgDBts2schema\"...";
 234                         if (! $this->tableExists("pg_ts_dict", $wgDBts2schema)) {
 235                                 print "<b>FAILED</b>. Make sure tsearch2 is installed. See <a href=";
 236                                 print "'http://www.devx.com/opensource/Article/21674/0/page/2'>this article</a>";
 237                                 print " for instructions.</li>\n";
 238                                 dieout("</ul>");
 239                         }
 240                         print "OK</li>\n";
 241
 242                         ## Does this user have the rights to the tsearch2 tables?
 243                         $ctype = pg_fetch_result($this->doQuery("SHOW lc_ctype"),0,0);
 244                         print "<li>Checking tsearch2 permissions...";
 245                         $SQL = "SELECT ts_name FROM $wgDBts2schema.pg_ts_cfg WHERE locale = '$ctype'";
 246                         $SQL .= " ORDER BY CASE WHEN ts_name <> 'default' THEN 1 ELSE 0 END";
 247                         error_reporting( 0 );
 248                         $res = $this->doQuery($SQL);
 249                         error_reporting( E_ALL );
 250                         if (!$res) {
 251                                 print "<b>FAILED</b>. Make sure that the user \"$wgDBuser\" has SELECT access to the tsearch2 tables</li>\n";
 252                                 dieout("</ul>");
 253                         }
 254                         print "OK</li>";
 255
 256                         ## Will the current locale work? Can we force it to?
 257                         print "<li>Verifying tsearch2 locale with $ctype...";
 258                         $rows = $this->numRows($res);
 259                         $resetlocale = 0;
 260                         if (!$rows) {
 261                                 print "<b>not found</b></li>\n";
 262                                 print "<li>Attempting to set default tsearch2 locale to \"$ctype\"...";
 263                                 $resetlocale = 1;
 264                         }
 265                         else {
 266                                 $tsname = pg_fetch_result($res, 0, 0);
 267                                 if ($tsname != 'default') {
 268                                         print "<b>not set to default ($tsname)</b>";
 269                                         print "<li>Attempting to change tsearch2 default locale to \"$ctype\"...";
 270                                         $resetlocale = 1;
 271                                 }
 272                         }
 273                         if ($resetlocale) {
 274                                 $SQL = "UPDATE $wgDBts2schema.pg_ts_cfg SET locale = '$ctype' WHERE ts_name = 'default'";
 275                                 $res = $this->doQuery($SQL);
 276                                 if (!$res) {
 277                                         print "<b>FAILED</b>. ";
 278                                         print "Please make sure that the locale in pg_ts_cfg for \"default\" is set to \"ctype\"</li>\n";
 279                                         dieout("</ul>");
 280                                 }
 281                                 print "OK</li>";
 282                         }
 283
 284                         ## Final test: try out a simple tsearch2 query
 285                         $SQL = "SELECT $wgDBts2schema.to_tsvector('default','MediaWiki tsearch2 testing')";
 286                         $res = $this->doQuery($SQL);
 287                         if (!$res) {
 288                                 print "<b>FAILED</b>. Specifically, \"$SQL\" did not work.</li>";
 289                                 dieout("</ul>");
 290                         }
 291                         print "OK</li>";
 292
 293                         ## Do we have plpgsql installed?
 294                         print "<li>Checking for Pl/Pgsql ...";
 295                         $SQL = "SELECT 1 FROM pg_catalog.pg_language WHERE lanname = 'plpgsql'";
 296                         $rows = $this->numRows($this->doQuery($SQL));
 297                         if ($rows < 1) {
 298                                 // plpgsql is not installed, but if we have a pg_pltemplate table, we should be able to create it
 299                                 print "not installed. Attempting to install Pl/Pgsql ...";
 300                                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON (n.oid = c.relnamespace) ".
 301                                         "WHERE relname = 'pg_pltemplate' AND nspname='pg_catalog'";
 302                                 $rows = $this->numRows($this->doQuery($SQL));
 303                                 if ($rows >= 1) {
 304                                         $result = $this->doQuery("CREATE LANGUAGE plpgsql");
 305                                         if (!$result) {
 306                                                 print "<b>FAILED</b>. You need to install the language plpgsql in the database <tt>$wgDBname</tt></li>";
 307                                                 dieout("</ul>");
 308                                         }
 309                                 }
 310                                 else {
 311                                         print "<b>FAILED</b>. You need to install the language plpgsql in the database <tt>$wgDBname</tt></li>";
 312                                         dieout("</ul>");
 313                                 }
 314                         }
 315                         print "OK</li>\n";
 316
 317                         ## Does the schema already exist? Who owns it?
 318                         $result = $this->schemaExists($wgDBmwschema);
 319                         if (!$result) {
 320                                 print "<li>Creating schema <b>$wgDBmwschema</b> ...";
 321                                 $result = $this->doQuery("CREATE SCHEMA $wgDBmwschema");
 322                                 if (!$result) {
 323                                         print "<b>FAILED</b>.</li>\n";
 324                                         dieout("</ul>");
 325                                 }
 326                                 print "OK</li>\n";
 327                         }
 328                         else if ($result != $user) {
 329                                 print "<li>Schema \"$wgDBmwschema\" exists but is not owned by \"$user\". Not ideal.</li>\n";
 330                         }
 331                         else {
 332                                 print "<li>Schema \"$wgDBmwschema\" exists and is owned by \"$user\". Excellent.</li>\n";
 333                         }
 334
 335                         ## Fix up the search paths if needed
 336                         print "<li>Setting the search path for user \"$user\" ...";
 337                         $path = $this->quote_ident($wgDBmwschema);
 338                         if ($wgDBts2schema !== $wgDBmwschema)
 339                                 $path .= ", ". $this->quote_ident($wgDBts2schema);
 340                         if ($wgDBmwschema !== 'public' and $wgDBts2schema !== 'public')
 341                                 $path .= ", public";
 342                         $SQL = "ALTER USER $safeuser SET search_path = $path";
 343                         $result = pg_query($this->mConn, $SQL);
 344                         if (!$result) {
 345                                 print "<b>FAILED</b>.</li>\n";
 346                                 dieout("</ul>");
 347                         }
 348                         print "OK</li>\n";
 349                         ## Set for the rest of this session
 350                         $SQL = "SET search_path = $path";
 351                         $result = pg_query($this->mConn, $SQL);
 352                         if (!$result) {
 353                                 print "<li>Failed to set search_path</li>\n";
 354                                 dieout("</ul>");
 355                         }
 356                         define( "POSTGRES_SEARCHPATH", $path );
 357                 }}
 358
 359                 global $wgCommandLineMode;
 360                 ## If called from the command-line (e.g. importDump), only show errors
 361                 if ($wgCommandLineMode) {
 362                         $this->doQuery("SET client_min_messages = 'ERROR'");
 363                 }
 364
 365                 return $this->mConn;
 366         }
 367
 368         /**
 369          * Closes a database connection, if it is open
 370          * Returns success, true if already closed
 371          */
 372         function close() {
 373                 $this->mOpened = false;
 374                 if ( $this->mConn ) {
 375                         return pg_close( $this->mConn );
 376                 } else {
 377                         return true;
 378                 }
 379         }
 380
 381         function doQuery( $sql ) {
 382                 return $this->mLastResult=pg_query( $this->mConn , $sql);
 383         }
 384
 385         function queryIgnore( $sql, $fname = '' ) {
 386                 return $this->query( $sql, $fname, true );
 387         }
 388
 389         function freeResult( $res ) {
 390                 if ( !@pg_free_result( $res ) ) {
 391                         throw new DBUnexpectedError($this,  "Unable to free Postgres result\n" );
 392                 }
 393         }
 394
 395         function fetchObject( $res ) {
 396                 @$row = pg_fetch_object( $res );
 397                 # FIXME: HACK HACK HACK HACK debug
 398
 399                 # TODO:
 400                 # hashar : not sure if the following test really trigger if the object
 401                 #          fetching failled.
 402                 if( pg_last_error($this->mConn) ) {
 403                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 404                 }
 405                 return $row;
 406         }
 407
 408         function fetchRow( $res ) {
 409                 @$row = pg_fetch_array( $res );
 410                 if( pg_last_error($this->mConn) ) {
 411                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 412                 }
 413                 return $row;
 414         }
 415
 416         function numRows( $res ) {
 417                 @$n = pg_num_rows( $res );
 418                 if( pg_last_error($this->mConn) ) {
 419                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 420                 }
 421                 return $n;
 422         }
 423         function numFields( $res ) { return pg_num_fields( $res ); }
 424         function fieldName( $res, $n ) { return pg_field_name( $res, $n ); }
 425
 426         /**
 427          * This must be called after nextSequenceVal
 428          */
 429         function insertId() {
 430                 return $this->mInsertId;
 431         }
 432
 433         function dataSeek( $res, $row ) { return pg_result_seek( $res, $row ); }
 434         function lastError() {
 435                 if ( $this->mConn ) {
 436                         return pg_last_error();
 437                 }
 438                 else {
 439                         return "No database connection";
 440                 }
 441         }
 442         function lastErrno() {
 443                 return pg_last_error() ? 1 : 0;
 444         }
 445
 446         function affectedRows() {
 447                 return pg_affected_rows( $this->mLastResult );
 448         }
 449
 450         /**
 451          * Returns information about an index
 452          * If errors are explicitly ignored, returns NULL on failure
 453          */
 454         function indexInfo( $table, $index, $fname = 'Database::indexExists' ) {
 455                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 456                 $res = $this->query( $sql, $fname );
 457                 if ( !$res ) {
 458                         return NULL;
 459                 }
 460
 461                 while ( $row = $this->fetchObject( $res ) ) {
 462                         if ( $row->indexname == $index ) {
 463                                 return $row;
 464
 465                                 // BUG: !!!! This code needs to be synced up with database.php
 466
 467                         }
 468                 }
 469                 return false;
 470         }
 471
 472         function indexUnique ($table, $index, $fname = 'Database::indexUnique' ) {
 473                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 474                         " AND indexdef LIKE 'CREATE UNIQUE%({$index})'";
 475                 $res = $this->query( $sql, $fname );
 476                 if ( !$res )
 477                         return NULL;
 478                 while ($row = $this->fetchObject( $res ))
 479                         return true;
 480                 return false;
 481
 482         }
 483
 484         function insert( $table, $a, $fname = 'Database::insert', $options = array() ) {
 485                 # Postgres doesn't support options
 486                 # We have a go at faking one of them
 487                 # TODO: DELAYED, LOW_PRIORITY
 488
 489                 if ( !is_array($options))
 490                         $options = array($options);
 491
 492                 if ( in_array( 'IGNORE', $options ) )
 493                         $oldIgnore = $this->ignoreErrors( true );
 494
 495                 # IGNORE is performed using single-row inserts, ignoring errors in each
 496                 # FIXME: need some way to distiguish between key collision and other types of error
 497                 $oldIgnore = $this->ignoreErrors( true );
 498                 if ( !is_array( reset( $a ) ) ) {
 499                         $a = array( $a );
 500                 }
 501                 foreach ( $a as $row ) {
 502                         parent::insert( $table, $row, $fname, array() );
 503                 }
 504                 $this->ignoreErrors( $oldIgnore );
 505                 $retVal = true;
 506
 507                 if ( in_array( 'IGNORE', $options ) )
 508                         $this->ignoreErrors( $oldIgnore );
 509
 510                 return $retVal;
 511         }
 512
 513         function tableName( $name ) {
 514                 # Replace reserved words with better ones
 515                 switch( $name ) {
 516                         case 'user':
 517                                 return 'mwuser';
 518                         case 'text':
 519                                 return 'pagecontent';
 520                         default:
 521                                 return $name;
 522                 }
 523         }
 524
 525         /**
 526          * Return the next in a sequence, save the value for retrieval via insertId()
 527          */
 528         function nextSequenceValue( $seqName ) {
 529                 $safeseq = preg_replace( "/'/", "''", $seqName );
 530                 $res = $this->query( "SELECT nextval('$safeseq')" );
 531                 $row = $this->fetchRow( $res );
 532                 $this->mInsertId = $row[0];
 533                 $this->freeResult( $res );
 534                 return $this->mInsertId;
 535         }
 536
 537         /**
 538          * Postgres does not have a "USE INDEX" clause, so return an empty string
 539          */
 540         function useIndexClause( $index ) {
 541                 return '';
 542         }
 543
 544         # REPLACE query wrapper
 545         # Postgres simulates this with a DELETE followed by INSERT
 546         # $row is the row to insert, an associative array
 547         # $uniqueIndexes is an array of indexes. Each element may be either a
 548         # field name or an array of field names
 549         #
 550         # It may be more efficient to leave off unique indexes which are unlikely to collide.
 551         # However if you do this, you run the risk of encountering errors which wouldn't have
 552         # occurred in MySQL
 553         function replace( $table, $uniqueIndexes, $rows, $fname = 'Database::replace' ) {
 554                 $table = $this->tableName( $table );
 555
 556                 if (count($rows)==0) {
 557                         return;
 558                 }
 559
 560                 # Single row case
 561                 if ( !is_array( reset( $rows ) ) ) {
 562                         $rows = array( $rows );
 563                 }
 564
 565                 foreach( $rows as $row ) {
 566                         # Delete rows which collide
 567                         if ( $uniqueIndexes ) {
 568                                 $sql = "DELETE FROM $table WHERE ";
 569                                 $first = true;
 570                                 foreach ( $uniqueIndexes as $index ) {
 571                                         if ( $first ) {
 572                                                 $first = false;
 573                                                 $sql .= "(";
 574                                         } else {
 575                                                 $sql .= ') OR (';
 576                                         }
 577                                         if ( is_array( $index ) ) {
 578                                                 $first2 = true;
 579                                                 foreach ( $index as $col ) {
 580                                                         if ( $first2 ) {
 581                                                                 $first2 = false;
 582                                                         } else {
 583                                                                 $sql .= ' AND ';
 584                                                         }
 585                                                         $sql .= $col.'=' . $this->addQuotes( $row[$col] );
 586                                                 }
 587                                         } else {
 588                                                 $sql .= $index.'=' . $this->addQuotes( $row[$index] );
 589                                         }
 590                                 }
 591                                 $sql .= ')';
 592                                 $this->query( $sql, $fname );
 593                         }
 594
 595                         # Now insert the row
 596                         $sql = "INSERT INTO $table (" . $this->makeList( array_keys( $row ), LIST_NAMES ) .') VALUES (' .
 597                                 $this->makeList( $row, LIST_COMMA ) . ')';
 598                         $this->query( $sql, $fname );
 599                 }
 600         }
 601
 602         # DELETE where the condition is a join
 603         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = "Database::deleteJoin" ) {
 604                 if ( !$conds ) {
 605                         throw new DBUnexpectedError($this,  'Database::deleteJoin() called with empty $conds' );
 606                 }
 607
 608                 $delTable = $this->tableName( $delTable );
 609                 $joinTable = $this->tableName( $joinTable );
 610                 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
 611                 if ( $conds != '*' ) {
 612                         $sql .= 'WHERE ' . $this->makeList( $conds, LIST_AND );
 613                 }
 614                 $sql .= ')';
 615
 616                 $this->query( $sql, $fname );
 617         }
 618
 619         # Returns the size of a text field, or -1 for "unlimited"
 620         function textFieldSize( $table, $field ) {
 621                 $table = $this->tableName( $table );
 622                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
 623                         FROM pg_class c, pg_attribute a, pg_type t
 624                         WHERE relname='$table' AND a.attrelid=c.oid AND
 625                                 a.atttypid=t.oid and a.attname='$field'";
 626                 $res =$this->query($sql);
 627                 $row=$this->fetchObject($res);
 628                 if ($row->ftype=="varchar") {
 629                         $size=$row->size-4;
 630                 } else {
 631                         $size=$row->size;
 632                 }
 633                 $this->freeResult( $res );
 634                 return $size;
 635         }
 636
 637         function lowPriorityOption() {
 638                 return '';
 639         }
 640
 641         function limitResult($sql, $limit,$offset) {
 642                 return "$sql LIMIT $limit ".(is_numeric($offset)?" OFFSET {$offset} ":"");
 643         }
 644
 645         /**
 646          * Returns an SQL expression for a simple conditional.
 647          * Uses CASE on Postgres
 648          *
 649          * @param string $cond SQL expression which will result in a boolean value
 650          * @param string $trueVal SQL expression to return if true
 651          * @param string $falseVal SQL expression to return if false
 652          * @return string SQL fragment
 653          */
 654         function conditional( $cond, $trueVal, $falseVal ) {
 655                 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
 656         }
 657
 658         # FIXME: actually detecting deadlocks might be nice
 659         function wasDeadlock() {
 660                 return false;
 661         }
 662
 663         function timestamp( $ts=0 ) {
 664                 return wfTimestamp(TS_POSTGRES,$ts);
 665         }
 666
 667         /**
 668          * Return aggregated value function call
 669          */
 670         function aggregateValue ($valuedata,$valuename='value') {
 671                 return $valuedata;
 672         }
 673
 674
 675         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 676                 $message = "A database error has occurred\n" .
 677                         "Query: $sql\n" .
 678                         "Function: $fname\n" .
 679                         "Error: $errno $error\n";
 680                 throw new DBUnexpectedError($this, $message);
 681         }
 682
 683         /**
 684          * @return string wikitext of a link to the server software's web site
 685          */
 686         function getSoftwareLink() {
 687                 return "[http://www.postgresql.org/ PostgreSQL]";
 688         }
 689
 690         /**
 691          * @return string Version information from the database
 692          */
 693         function getServerVersion() {
 694                 $res = $this->query( "SELECT version()" );
 695                 $row = $this->fetchRow( $res );
 696                 $version = $row[0];
 697                 $this->freeResult( $res );
 698                 return $version;
 699         }
 700
 701
 702         /**
 703          * Query whether a given table exists (in the given schema, or the default mw one if not given)
 704          */
 705         function tableExists( $table, $schema = false ) {
 706                 global $wgDBmwschema;
 707                 if (! $schema )
 708                         $schema = $wgDBmwschema;
 709                 $etable = preg_replace("/'/", "''", $table);
 710                 $eschema = preg_replace("/'/", "''", $schema);
 711                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
 712                         . "WHERE c.relnamespace = n.oid AND c.relname = '$etable' AND n.nspname = '$eschema' "
 713                         . "AND c.relkind IN ('r','v')";
 714                 $res = $this->query( $SQL );
 715                 $count = $res ? pg_num_rows($res) : 0;
 716                 if ($res)
 717                         $this->freeResult( $res );
 718                 return $count;
 719         }
 720
 721
 722         /**
 723          * Query whether a given schema exists. Returns the name of the owner
 724          */
 725         function schemaExists( $schema ) {
 726                 $eschema = preg_replace("/'/", "''", $schema);
 727                 $SQL = "SELECT rolname FROM pg_catalog.pg_namespace n, pg_catalog.pg_roles r "
 728                                 ."WHERE n.nspowner=r.oid AND n.nspname = '$eschema'";
 729                 $res = $this->query( $SQL );
 730                 $owner = $res ? pg_num_rows($res) ? pg_fetch_result($res, 0, 0) : false : false;
 731                 if ($res)
 732                         $this->freeResult($res);
 733                 return $owner;
 734         }
 735
 736         /**
 737          * Query whether a given column exists in the mediawiki schema
 738          */
 739         function fieldExists( $table, $field ) {
 740                 global $wgDBmwschema;
 741                 $etable = preg_replace("/'/", "''", $table);
 742                 $eschema = preg_replace("/'/", "''", $wgDBmwschema);
 743                 $ecol = preg_replace("/'/", "''", $field);
 744                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n, pg_catalog.pg_attribute a "
 745                         . "WHERE c.relnamespace = n.oid AND c.relname = '$etable' AND n.nspname = '$eschema' "
 746                         . "AND a.attrelid = c.oid AND a.attname = '$ecol'";
 747                 $res = $this->query( $SQL );
 748                 $count = $res ? pg_num_rows($res) : 0;
 749                 if ($res)
 750                         $this->freeResult( $res );
 751                 return $count;
 752         }
 753
 754         function fieldInfo( $table, $field ) {
 755                 $res = $this->query( "SELECT $field FROM $table LIMIT 1" );
 756                 $type = pg_field_type( $res, 0 );
 757                 return $type;
 758         }
 759
 760         function begin( $fname = 'DatabasePostgrs::begin' ) {
 761                 $this->query( 'BEGIN', $fname );
 762                 $this->mTrxLevel = 1;
 763         }
 764         function immediateCommit( $fname = 'DatabasePostgres::immediateCommit' ) {
 765                 return true;
 766         }
 767         function commit( $fname = 'DatabasePostgres::commit' ) {
 768                 $this->query( 'COMMIT', $fname );
 769                 $this->mTrxLevel = 0;
 770         }
 771
 772         /* Not even sure why this is used in the main codebase... */
 773         function limitResultForUpdate($sql, $num) {
 774                 return $sql;
 775         }
 776
 777         function setup_database() {
 778                 global $wgVersion, $wgDBmwschema, $wgDBts2schema, $wgDBport;
 779
 780                 dbsource( "../maintenance/postgres/tables.sql", $this);
 781
 782                 ## Update version information
 783                 $mwv = $this->addQuotes($wgVersion);
 784                 $pgv = $this->addQuotes($this->getServerVersion());
 785                 $pgu = $this->addQuotes($this->mUser);
 786                 $mws = $this->addQuotes($wgDBmwschema);
 787                 $tss = $this->addQuotes($wgDBts2schema);
 788                 $pgp = $this->addQuotes($wgDBport);
 789                 $dbn = $this->addQuotes($this->mDBname);
 790                 $ctype = pg_fetch_result($this->doQuery("SHOW lc_ctype"),0,0);
 791
 792                 $SQL = "UPDATE mediawiki_version SET mw_version=$mwv, pg_version=$pgv, pg_user=$pgu, ".
 793                                 "mw_schema = $mws, ts2_schema = $tss, pg_port=$pgp, pg_dbname=$dbn, ".
 794                                 "ctype = '$ctype' ".
 795                                 "WHERE type = 'Creation'";
 796                 $this->query($SQL);
 797
 798                 ## Avoid the non-standard "REPLACE INTO" syntax
 799                 $f = fopen( "../maintenance/interwiki.sql", 'r' );
 800                 if ($f == false ) {
 801                         dieout( "<li>Could not find the interwiki.sql file");
 802                 }
 803                 ## We simply assume it is already empty as we have just created it
 804                 $SQL = "INSERT INTO interwiki(iw_prefix,iw_url,iw_local) VALUES ";
 805                 while ( ! feof( $f ) ) {
 806                         $line = fgets($f,1024);
 807                         $matches = array();
 808                         if (!preg_match('/^\s*(\(.+?),(\d)\)/', $line, $matches)) {
 809                                 continue;
 810                         }
 811                         $this->query("$SQL $matches[1],$matches[2])");
 812                 }
 813                 print " (table interwiki successfully populated)...\n";
 814         }
 815
 816         function encodeBlob($b) {
 817                 return array('bytea',pg_escape_bytea($b));
 818         }
 819         function decodeBlob($b) {
 820                 return pg_unescape_bytea( $b );
 821         }
 822
 823         function strencode( $s ) { ## Should not be called by us
 824                 return pg_escape_string( $s );
 825         }
 826
 827         function addQuotes( $s ) {
 828                 if ( is_null( $s ) ) {
 829                         return 'NULL';
 830                 } else if (is_array( $s )) { ## Assume it is bytea data
 831                         return "E'$s[1]'";
 832                 }
 833                 return "'" . pg_escape_string($s) . "'";
 834                 // Unreachable: return "E'" . pg_escape_string($s) . "'";
 835         }
 836
 837         function quote_ident( $s ) {
 838                 return '"' . preg_replace( '/"/', '""', $s) . '"';
 839         }
 840
 841 }
 842
 843 ?>