includes/DatabasePostgres.php

   1 <?php
   2
   3 /**
   4  * This is PostgreSQL database abstraction layer.
   5  *
   6  * As it includes more generic version for DB functions,
   7  * than MySQL ones, some of them should be moved to parent
   8  * Database class.
   9  *
  10  * @package MediaWiki
  11  */
  12
  13 /**
  14  * Depends on database
  15  */
  16 require_once( 'Database.php' );
  17
  18 class DatabasePostgres extends Database {
  19         var $mInsertId = NULL;
  20         var $mLastResult = NULL;
  21
  22         function DatabasePostgres($server = false, $user = false, $password = false, $dbName = false,
  23                 $failFunction = false, $flags = 0 )
  24         {
  25
  26                 global $wgOut, $wgDBprefix, $wgCommandLineMode;
  27                 # Can't get a reference if it hasn't been set yet
  28                 if ( !isset( $wgOut ) ) {
  29                         $wgOut = NULL;
  30                 }
  31                 $this->mOut =& $wgOut;
  32                 $this->mFailFunction = $failFunction;
  33                 $this->mFlags = $flags;
  34
  35                 $this->open( $server, $user, $password, $dbName);
  36
  37         }
  38
  39         static function newFromParams( $server = false, $user = false, $password = false, $dbName = false,
  40                 $failFunction = false, $flags = 0)
  41         {
  42                 return new DatabasePostgres( $server, $user, $password, $dbName, $failFunction, $flags );
  43         }
  44
  45         /**
  46          * Usually aborts on failure
  47          * If the failFunction is set to a non-zero integer, returns success
  48          */
  49         function open( $server, $user, $password, $dbName ) {
  50                 # Test for PostgreSQL support, to avoid suppressed fatal error
  51                 if ( !function_exists( 'pg_connect' ) ) {
  52                         throw new DBConnectionError( $this, "PostgreSQL functions missing, have you compiled PHP with the --with-pgsql option?\n" );
  53                 }
  54
  55                 global $wgDBport;
  56
  57                 $this->close();
  58                 $this->mServer = $server;
  59                 $port = $wgDBport;
  60                 $this->mUser = $user;
  61                 $this->mPassword = $password;
  62                 $this->mDBname = $dbName;
  63
  64                 $success = false;
  65
  66                 $hstring="";
  67                 if ($server!=false && $server!="") {
  68                         $hstring="host=$server ";
  69                 }
  70                 if ($port!=false && $port!="") {
  71                         $hstring .= "port=$port ";
  72                 }
  73
  74                 error_reporting( E_ALL );
  75
  76                 @$this->mConn = pg_connect("$hstring dbname=$dbName user=$user password=$password");
  77
  78                 if ( $this->mConn == false ) {
  79                         wfDebug( "DB connection error\n" );
  80                         wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
  81                         wfDebug( $this->lastError()."\n" );
  82                         return false;
  83                 }
  84
  85                 $this->mOpened = true;
  86                 ## If this is the initial connection, setup the schema stuff
  87                 if (defined('MEDIAWIKI_INSTALL') and !defined('POSTGRES_SEARCHPATH')) {
  88                         global $wgDBmwschema, $wgDBts2schema;
  89
  90                         ## Do we have the basic tsearch2 table?
  91                         print "<li>Checking for tsearch2 ...";
  92                         if (! $this->tableExists("pg_ts_dict", $wgDBts2schema)) {
  93                                 print "FAILED. Make sure tsearch2 is installed. See <a href=";
  94                                 print "'http://www.devx.com/opensource/Article/21674/0/page/2'>this article</a>";
  95                                 print " for instructions.</li>\n";
  96                                 dieout("</ul>");
  97                         }
  98                         print "OK</li>\n";
  99
 100                         ## Does the schema already exist? Who owns it?
 101                         $result = $this->schemaExists($wgDBmwschema);
 102                         if (!$result) {
 103                                 print "<li>Creating schema <b>$wgDBmwschema</b> ...";
 104                                 $result = $this->doQuery("CREATE SCHEMA $wgDBmwschema");
 105                                 if (!$result) {
 106                                         print "FAILED.</li>\n";
 107                                         return false;
 108                                 }
 109                                 print "ok</li>\n";
 110                         }
 111                         else if ($result != $user) {
 112                                 print "<li>Schema <b>$wgDBmwschema</b> exists but is not owned by <b>$user</b>. Not ideal.</li>\n";
 113                         }
 114                         else {
 115                                 print "<li>Schema <b>$wgDBmwschema</b> exists and is owned by <b>$user ($result)</b>. Excellent.</li>\n";
 116                         }
 117
 118                         ## Fix up the search paths if needed
 119                         print "<li>Setting the search path for user <b>$user</b> ...";
 120                         $path = "$wgDBmwschema";
 121                         if ($wgDBts2schema !== $wgDBmwschema)
 122                                 $path .= ", $wgDBts2schema";
 123                         if ($wgDBmwschema !== 'public' and $wgDBts2schema !== 'public')
 124                                 $path .= ", public";
 125                         $SQL = "ALTER USER $user SET search_path = $path";
 126                         $result = pg_query($this->mConn, $SQL);
 127                         if (!$result) {
 128                                 print "FAILED.</li>\n";
 129                                 return false;
 130                         }
 131                         print "ok</li>\n";
 132                         ## Set for the rest of this session
 133                         $SQL = "SET search_path = $path";
 134                         $result = pg_query($this->mConn, $SQL);
 135                         if (!$result) {
 136                                 print "<li>Failed to set search_path</li>\n";
 137                                 return false;
 138                         }
 139                         define( "POSTGRES_SEARCHPATH", $path );
 140                 }
 141
 142                 return $this->mConn;
 143         }
 144
 145         /**
 146          * Closes a database connection, if it is open
 147          * Returns success, true if already closed
 148          */
 149         function close() {
 150                 $this->mOpened = false;
 151                 if ( $this->mConn ) {
 152                         return pg_close( $this->mConn );
 153                 } else {
 154                         return true;
 155                 }
 156         }
 157
 158         function doQuery( $sql ) {
 159                 return $this->mLastResult=pg_query( $this->mConn , $sql);
 160         }
 161
 162         function queryIgnore( $sql, $fname = '' ) {
 163                 return $this->query( $sql, $fname, true );
 164         }
 165
 166         function freeResult( $res ) {
 167                 if ( !@pg_free_result( $res ) ) {
 168                         throw new DBUnexpectedError($this,  "Unable to free PostgreSQL result\n" );
 169                 }
 170         }
 171
 172         function fetchObject( $res ) {
 173                 @$row = pg_fetch_object( $res );
 174                 # FIXME: HACK HACK HACK HACK debug
 175
 176                 # TODO:
 177                 # hashar : not sure if the following test really trigger if the object
 178                 #          fetching failled.
 179                 if( pg_last_error($this->mConn) ) {
 180                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 181                 }
 182                 return $row;
 183         }
 184
 185         function fetchRow( $res ) {
 186                 @$row = pg_fetch_array( $res );
 187                 if( pg_last_error($this->mConn) ) {
 188                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 189                 }
 190                 return $row;
 191         }
 192
 193         function numRows( $res ) {
 194                 @$n = pg_num_rows( $res );
 195                 if( pg_last_error($this->mConn) ) {
 196                         throw new DBUnexpectedError($this,  'SQL error: ' . htmlspecialchars( pg_last_error($this->mConn) ) );
 197                 }
 198                 return $n;
 199         }
 200         function numFields( $res ) { return pg_num_fields( $res ); }
 201         function fieldName( $res, $n ) { return pg_field_name( $res, $n ); }
 202
 203         /**
 204          * This must be called after nextSequenceVal
 205          */
 206         function insertId() {
 207                 return $this->mInsertId;
 208         }
 209
 210         function dataSeek( $res, $row ) { return pg_result_seek( $res, $row ); }
 211         function lastError() {
 212                 if ( $this->mConn ) {
 213                         return pg_last_error();
 214                 }
 215                 else {
 216                         return "No database connection";
 217                 }
 218         }
 219         function lastErrno() { return 1; }
 220
 221         function affectedRows() {
 222                 return pg_affected_rows( $this->mLastResult );
 223         }
 224
 225         /**
 226          * Returns information about an index
 227          * If errors are explicitly ignored, returns NULL on failure
 228          */
 229         function indexInfo( $table, $index, $fname = 'Database::indexExists' ) {
 230                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
 231                 $res = $this->query( $sql, $fname );
 232                 if ( !$res ) {
 233                         return NULL;
 234                 }
 235
 236                 while ( $row = $this->fetchObject( $res ) ) {
 237                         if ( $row->indexname == $index ) {
 238                                 return $row;
 239                         }
 240                 }
 241                 return false;
 242         }
 243
 244         function indexUnique ($table, $index, $fname = 'Database::indexUnique' ) {
 245                 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'".
 246                         " AND indexdef LIKE 'CREATE UNIQUE%({$index})'";
 247                 $res = $this->query( $sql, $fname );
 248                 if ( !$res )
 249                         return NULL;
 250                 while ($row = $this->fetchObject( $res ))
 251                         return true;
 252                 return false;
 253
 254         }
 255
 256         function insert( $table, $a, $fname = 'Database::insert', $options = array() ) {
 257                 # PostgreSQL doesn't support options
 258                 # We have a go at faking one of them
 259                 # TODO: DELAYED, LOW_PRIORITY
 260
 261                 if ( !is_array($options))
 262                         $options = array($options);
 263
 264                 if ( in_array( 'IGNORE', $options ) )
 265                         $oldIgnore = $this->ignoreErrors( true );
 266
 267                 # IGNORE is performed using single-row inserts, ignoring errors in each
 268                 # FIXME: need some way to distiguish between key collision and other types of error
 269                 $oldIgnore = $this->ignoreErrors( true );
 270                 if ( !is_array( reset( $a ) ) ) {
 271                         $a = array( $a );
 272                 }
 273                 foreach ( $a as $row ) {
 274                         parent::insert( $table, $row, $fname, array() );
 275                 }
 276                 $this->ignoreErrors( $oldIgnore );
 277                 $retVal = true;
 278
 279                 if ( in_array( 'IGNORE', $options ) )
 280                         $this->ignoreErrors( $oldIgnore );
 281
 282                 return $retVal;
 283         }
 284
 285         function tableName( $name ) {
 286                 # Replace backticks into double quotes
 287                 $name = strtr($name,'`','"');
 288
 289                 # Now quote PG reserved keywords
 290                 switch( $name ) {
 291                         case 'user':
 292                         case 'old':
 293                         case 'group':
 294                                 return '"' . $name . '"';
 295
 296                         default:
 297                                 return $name;
 298                 }
 299         }
 300
 301         function strencode( $s ) {
 302                 return pg_escape_string( $s );
 303         }
 304
 305         /**
 306          * Return the next in a sequence, save the value for retrieval via insertId()
 307          */
 308         function nextSequenceValue( $seqName ) {
 309                 $value = $this->selectField(''," nextval('" . $seqName . "')");
 310                 $this->mInsertId = $value;
 311                 return $value;
 312         }
 313
 314         /**
 315          * USE INDEX clause
 316          * PostgreSQL doesn't have them and returns ""
 317          */
 318         function useIndexClause( $index ) {
 319                 return '';
 320         }
 321
 322         # REPLACE query wrapper
 323         # PostgreSQL simulates this with a DELETE followed by INSERT
 324         # $row is the row to insert, an associative array
 325         # $uniqueIndexes is an array of indexes. Each element may be either a
 326         # field name or an array of field names
 327         #
 328         # It may be more efficient to leave off unique indexes which are unlikely to collide.
 329         # However if you do this, you run the risk of encountering errors which wouldn't have
 330         # occurred in MySQL
 331         function replace( $table, $uniqueIndexes, $rows, $fname = 'Database::replace' ) {
 332                 $table = $this->tableName( $table );
 333
 334                 if (count($rows)==0) {
 335                         return;
 336                 }
 337
 338                 # Single row case
 339                 if ( !is_array( reset( $rows ) ) ) {
 340                         $rows = array( $rows );
 341                 }
 342
 343                 foreach( $rows as $row ) {
 344                         # Delete rows which collide
 345                         if ( $uniqueIndexes ) {
 346                                 $sql = "DELETE FROM $table WHERE ";
 347                                 $first = true;
 348                                 foreach ( $uniqueIndexes as $index ) {
 349                                         if ( $first ) {
 350                                                 $first = false;
 351                                                 $sql .= "(";
 352                                         } else {
 353                                                 $sql .= ') OR (';
 354                                         }
 355                                         if ( is_array( $index ) ) {
 356                                                 $first2 = true;
 357                                                 foreach ( $index as $col ) {
 358                                                         if ( $first2 ) {
 359                                                                 $first2 = false;
 360                                                         } else {
 361                                                                 $sql .= ' AND ';
 362                                                         }
 363                                                         $sql .= $col.'=' . $this->addQuotes( $row[$col] );
 364                                                 }
 365                                         } else {
 366                                                 $sql .= $index.'=' . $this->addQuotes( $row[$index] );
 367                                         }
 368                                 }
 369                                 $sql .= ')';
 370                                 $this->query( $sql, $fname );
 371                         }
 372
 373                         # Now insert the row
 374                         $sql = "INSERT INTO $table (" . $this->makeList( array_keys( $row ), LIST_NAMES ) .') VALUES (' .
 375                                 $this->makeList( $row, LIST_COMMA ) . ')';
 376                         $this->query( $sql, $fname );
 377                 }
 378         }
 379
 380         # DELETE where the condition is a join
 381         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = "Database::deleteJoin" ) {
 382                 if ( !$conds ) {
 383                         throw new DBUnexpectedError($this,  'Database::deleteJoin() called with empty $conds' );
 384                 }
 385
 386                 $delTable = $this->tableName( $delTable );
 387                 $joinTable = $this->tableName( $joinTable );
 388                 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
 389                 if ( $conds != '*' ) {
 390                         $sql .= 'WHERE ' . $this->makeList( $conds, LIST_AND );
 391                 }
 392                 $sql .= ')';
 393
 394                 $this->query( $sql, $fname );
 395         }
 396
 397         # Returns the size of a text field, or -1 for "unlimited"
 398         function textFieldSize( $table, $field ) {
 399                 $table = $this->tableName( $table );
 400                 $sql = "SELECT t.typname as ftype,a.atttypmod as size
 401                         FROM pg_class c, pg_attribute a, pg_type t
 402                         WHERE relname='$table' AND a.attrelid=c.oid AND
 403                                 a.atttypid=t.oid and a.attname='$field'";
 404                 $res =$this->query($sql);
 405                 $row=$this->fetchObject($res);
 406                 if ($row->ftype=="varchar") {
 407                         $size=$row->size-4;
 408                 } else {
 409                         $size=$row->size;
 410                 }
 411                 $this->freeResult( $res );
 412                 return $size;
 413         }
 414
 415         function lowPriorityOption() {
 416                 return '';
 417         }
 418
 419         function limitResult($sql, $limit,$offset) {
 420                 return "$sql LIMIT $limit ".(is_numeric($offset)?" OFFSET {$offset} ":"");
 421         }
 422
 423         /**
 424          * Returns an SQL expression for a simple conditional.
 425          * Uses CASE on PostgreSQL.
 426          *
 427          * @param string $cond SQL expression which will result in a boolean value
 428          * @param string $trueVal SQL expression to return if true
 429          * @param string $falseVal SQL expression to return if false
 430          * @return string SQL fragment
 431          */
 432         function conditional( $cond, $trueVal, $falseVal ) {
 433                 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
 434         }
 435
 436         # FIXME: actually detecting deadlocks might be nice
 437         function wasDeadlock() {
 438                 return false;
 439         }
 440
 441         # Return DB-style timestamp used for MySQL schema
 442         function timestamp( $ts=0 ) {
 443                 return wfTimestamp(TS_DB,$ts);
 444         }
 445
 446         /**
 447          * Return aggregated value function call
 448          */
 449         function aggregateValue ($valuedata,$valuename='value') {
 450                 return $valuedata;
 451         }
 452
 453
 454         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 455                 $message = "A database error has occurred\n" .
 456                         "Query: $sql\n" .
 457                         "Function: $fname\n" .
 458                         "Error: $errno $error\n";
 459                 throw new DBUnexpectedError($this, $message);
 460         }
 461
 462         /**
 463          * @return string wikitext of a link to the server software's web site
 464          */
 465         function getSoftwareLink() {
 466                 return "[http://www.postgresql.org/ PostgreSQL]";
 467         }
 468
 469         /**
 470          * @return string Version information from the database
 471          */
 472         function getServerVersion() {
 473                 $res = $this->query( "SELECT version()" );
 474                 $row = $this->fetchRow( $res );
 475                 $version = $row[0];
 476                 $this->freeResult( $res );
 477                 return $version;
 478         }
 479
 480
 481         /**
 482          * Query whether a given table exists (in the given schema, or the default mw one if not given)
 483          */
 484         function tableExists( $table, $schema = false ) {
 485                 global $wgDBmwschema;
 486                 if (! $schema )
 487                         $schema = $wgDBmwschema;
 488                 $etable = preg_replace("/'/", "''", $table);
 489                 $eschema = preg_replace("/'/", "''", $schema);
 490                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
 491                         . "WHERE c.relnamespace = n.oid AND c.relname = '$etable' AND n.nspname = '$eschema'";
 492                 $res = $this->query( $SQL );
 493                 $count = $res ? pg_num_rows($res) : 0;
 494                 if ($res)
 495                         $this->freeResult( $res );
 496                 return $count;
 497         }
 498
 499
 500         /**
 501          * Query whether a given schema exists. Returns the name of the owner
 502          */
 503         function schemaExists( $schema ) {
 504                 $eschema = preg_replace("/'/", "''", $schema);
 505                 $SQL = "SELECT rolname FROM pg_catalog.pg_namespace n, pg_catalog.pg_roles r "
 506                                 ."WHERE n.nspowner=r.oid AND n.nspname = '$eschema'";
 507                 $res = $this->query( $SQL );
 508                 $owner = $res ? pg_num_rows($res) ? pg_fetch_result($res, 0, 0) : false : false;
 509                 if ($res)
 510                         $this->freeResult($res);
 511                 return $owner;
 512         }
 513
 514         /**
 515          * Query whether a given column exists in the mediawiki schema
 516          */
 517         function fieldExists( $table, $field ) {
 518                 global $wgDBmwschema;
 519                 $etable = preg_replace("/'/", "''", $table);
 520                 $eschema = preg_replace("/'/", "''", $wgDBmwschema);
 521                 $ecol = preg_replace("/'/", "''", $field);
 522                 $SQL = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n, pg_catalog.pg_attribute a "
 523                         . "WHERE c.relnamespace = n.oid AND c.relname = '$etable' AND n.nspname = '$eschema' "
 524                         . "AND a.attrelid = c.oid AND a.attname = '$ecol'";
 525                 $res = $this->query( $SQL );
 526                 $count = $res ? pg_num_rows($res) : 0;
 527                 if ($res)
 528                         $this->freeResult( $res );
 529                 return $count;
 530         }
 531
 532         function fieldInfo( $table, $field ) {
 533                 $res = $this->query( "SELECT $field FROM $table LIMIT 1" );
 534                 $type = pg_field_type( $res, 0 );
 535                 return $type;
 536         }
 537
 538         function commit( $fname = 'Database::commit' ) {
 539                 ## XXX
 540                 return;
 541                 $this->query( 'COMMIT', $fname );
 542                 $this->mTrxLevel = 0;
 543         }
 544
 545         /* Not even sure why this is used in the main codebase... */
 546         function limitResultForUpdate($sql, $num) {
 547                 return $sql;
 548         }
 549
 550         function update_interwiki() {
 551                 ## Avoid the non-standard "REPLACE INTO" syntax
 552                 ## Called by config/index.php
 553                 $f = fopen( "../maintenance/interwiki.sql", 'r' );
 554                 if ($f == false ) {
 555                         dieout( "<li>Could not find the interwiki.sql file");
 556                 }
 557                 ## We simply assume it is already empty as we have just created it
 558                 $SQL = "INSERT INTO interwiki(iw_prefix,iw_url,iw_local) VALUES ";
 559                 while ( ! feof( $f ) ) {
 560                         $line = fgets($f,1024);
 561                         if (!preg_match("/^\s*(\(.+?),(\d)\)/", $line, $matches)) {
 562                                 continue;
 563                         }
 564                         $yesno = $matches[2]; ## ? "'true'" : "'false'";
 565                         $this->query("$SQL $matches[1],$matches[2])");
 566                 }
 567                 print " (table interwiki successfully populated)...\n";
 568         }
 569
 570 }
 571
 572 ?>