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