includes/DatabasePostgres.php

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