includes/DatabasePostgres.php

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