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