includes/db/DatabaseMysql.php

   1 <?php
   2 /**
   3  * Database abstraction object for mySQL
   4  * Inherit all methods and properties of Database::Database()
   5  *
   6  * @ingroup Database
   7  * @see Database
   8  */
   9 class DatabaseMysql extends DatabaseBase {
  10         function getType() {
  11                 return 'mysql';
  12         }
  13
  14         /*private*/ function doQuery( $sql ) {
  15                 if( $this->bufferResults() ) {
  16                         $ret = mysql_query( $sql, $this->mConn );
  17                 } else {
  18                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
  19                 }
  20                 return $ret;
  21         }
  22
  23         function open( $server, $user, $password, $dbName ) {
  24                 global $wgAllDBsAreLocalhost;
  25                 wfProfileIn( __METHOD__ );
  26
  27                 # Test for missing mysql.so
  28                 # First try to load it
  29                 if (!@extension_loaded('mysql')) {
  30                         @dl('mysql.so');
  31                 }
  32
  33                 # Fail now
  34                 # Otherwise we get a suppressed fatal error, which is very hard to track down
  35                 if ( !function_exists( 'mysql_connect' ) ) {
  36                         throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
  37                 }
  38
  39                 # Debugging hack -- fake cluster
  40                 if ( $wgAllDBsAreLocalhost ) {
  41                         $realServer = 'localhost';
  42                 } else {
  43                         $realServer = $server;
  44                 }
  45                 $this->close();
  46                 $this->mServer = $server;
  47                 $this->mUser = $user;
  48                 $this->mPassword = $password;
  49                 $this->mDBname = $dbName;
  50
  51                 $success = false;
  52
  53                 wfProfileIn("dbconnect-$server");
  54
  55                 # The kernel's default SYN retransmission period is far too slow for us,
  56                 # so we use a short timeout plus a manual retry. Retrying means that a small
  57                 # but finite rate of SYN packet loss won't cause user-visible errors.
  58                 $this->mConn = false;
  59                 if ( ini_get( 'mysql.connect_timeout' ) <= 3 ) {
  60                         $numAttempts = 2;
  61                 } else {
  62                         $numAttempts = 1;
  63                 }
  64                 $this->installErrorHandler();
  65                 for ( $i = 0; $i < $numAttempts && !$this->mConn; $i++ ) {
  66                         if ( $i > 1 ) {
  67                                 usleep( 1000 );
  68                         }
  69                         if ( $this->mFlags & DBO_PERSISTENT ) {
  70                                 $this->mConn = mysql_pconnect( $realServer, $user, $password );
  71                         } else {
  72                                 # Create a new connection...
  73                                 $this->mConn = mysql_connect( $realServer, $user, $password, true );
  74                         }
  75                         if ($this->mConn === false) {
  76                                 #$iplus = $i + 1;
  77                                 #wfLogDBError("Connect loop error $iplus of $max ($server): " . mysql_errno() . " - " . mysql_error()."\n");
  78                         }
  79                 }
  80                 $phpError = $this->restoreErrorHandler();
  81                 # Always log connection errors
  82                 if ( !$this->mConn ) {
  83                         $error = $this->lastError();
  84                         if ( !$error ) {
  85                                 $error = $phpError;
  86                         }
  87                         wfLogDBError( "Error connecting to {$this->mServer}: $error\n" );
  88                         wfDebug( "DB connection error\n" );
  89                         wfDebug( "Server: $server, User: $user, Password: " .
  90                                 substr( $password, 0, 3 ) . "..., error: " . mysql_error() . "\n" );
  91                         $success = false;
  92                 }
  93
  94                 wfProfileOut("dbconnect-$server");
  95
  96                 if ( $dbName != '' && $this->mConn !== false ) {
  97                         $success = @/**/mysql_select_db( $dbName, $this->mConn );
  98                         if ( !$success ) {
  99                                 $error = "Error selecting database $dbName on server {$this->mServer} " .
 100                                         "from client host " . wfHostname() . "\n";
 101                                 wfLogDBError(" Error selecting database $dbName on server {$this->mServer} \n");
 102                                 wfDebug( $error );
 103                         }
 104                 } else {
 105                         # Delay USE query
 106                         $success = (bool)$this->mConn;
 107                 }
 108
 109                 if ( $success ) {
 110                         $version = $this->getServerVersion();
 111                         if ( version_compare( $version, '4.1' ) >= 0 ) {
 112                                 // Tell the server we're communicating with it in UTF-8.
 113                                 // This may engage various charset conversions.
 114                                 global $wgDBmysql5;
 115                                 if( $wgDBmysql5 ) {
 116                                         $this->query( 'SET NAMES utf8', __METHOD__ );
 117                                 }
 118                                 // Turn off strict mode
 119                                 $this->query( "SET sql_mode = ''", __METHOD__ );
 120                         }
 121
 122                         // Turn off strict mode if it is on
 123                 } else {
 124                         $this->reportConnectionError( $phpError );
 125                 }
 126
 127                 $this->mOpened = $success;
 128                 wfProfileOut( __METHOD__ );
 129                 return $success;
 130         }
 131
 132         function close() {
 133                 $this->mOpened = false;
 134                 if ( $this->mConn ) {
 135                         if ( $this->trxLevel() ) {
 136                                 $this->commit();
 137                         }
 138                         return mysql_close( $this->mConn );
 139                 } else {
 140                         return true;
 141                 }
 142         }
 143
 144         function freeResult( $res ) {
 145                 if ( $res instanceof ResultWrapper ) {
 146                         $res = $res->result;
 147                 }
 148                 if ( !@/**/mysql_free_result( $res ) ) {
 149                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 150                 }
 151         }
 152
 153         function fetchObject( $res ) {
 154                 if ( $res instanceof ResultWrapper ) {
 155                         $res = $res->result;
 156                 }
 157                 @/**/$row = mysql_fetch_object( $res );
 158                 if( $this->lastErrno() ) {
 159                         throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
 160                 }
 161                 return $row;
 162         }
 163
 164         function fetchRow( $res ) {
 165                 if ( $res instanceof ResultWrapper ) {
 166                         $res = $res->result;
 167                 }
 168                 @/**/$row = mysql_fetch_array( $res );
 169                 if ( $this->lastErrno() ) {
 170                         throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
 171                 }
 172                 return $row;
 173         }
 174
 175         function numRows( $res ) {
 176                 if ( $res instanceof ResultWrapper ) {
 177                         $res = $res->result;
 178                 }
 179                 @/**/$n = mysql_num_rows( $res );
 180                 if( $this->lastErrno() ) {
 181                         throw new DBUnexpectedError( $this, 'Error in numRows(): ' . htmlspecialchars( $this->lastError() ) );
 182                 }
 183                 return $n;
 184         }
 185
 186         function numFields( $res ) {
 187                 if ( $res instanceof ResultWrapper ) {
 188                         $res = $res->result;
 189                 }
 190                 return mysql_num_fields( $res );
 191         }
 192
 193         function fieldName( $res, $n ) {
 194                 if ( $res instanceof ResultWrapper ) {
 195                         $res = $res->result;
 196                 }
 197                 return mysql_field_name( $res, $n );
 198         }
 199
 200         function insertId() { return mysql_insert_id( $this->mConn ); }
 201
 202         function dataSeek( $res, $row ) {
 203                 if ( $res instanceof ResultWrapper ) {
 204                         $res = $res->result;
 205                 }
 206                 return mysql_data_seek( $res, $row );
 207         }
 208
 209         function lastErrno() {
 210                 if ( $this->mConn ) {
 211                         return mysql_errno( $this->mConn );
 212                 } else {
 213                         return mysql_errno();
 214                 }
 215         }
 216
 217         function lastError() {
 218                 if ( $this->mConn ) {
 219                         # Even if it's non-zero, it can still be invalid
 220                         wfSuppressWarnings();
 221                         $error = mysql_error( $this->mConn );
 222                         if ( !$error ) {
 223                                 $error = mysql_error();
 224                         }
 225                         wfRestoreWarnings();
 226                 } else {
 227                         $error = mysql_error();
 228                 }
 229                 if( $error ) {
 230                         $error .= ' (' . $this->mServer . ')';
 231                 }
 232                 return $error;
 233         }
 234
 235         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
 236
 237         /**
 238          * Estimate rows in dataset
 239          * Returns estimated count, based on EXPLAIN output
 240          * Takes same arguments as Database::select()
 241          */
 242         public function estimateRowCount( $table, $vars='*', $conds='', $fname = 'Database::estimateRowCount', $options = array() ) {
 243                 $options['EXPLAIN'] = true;
 244                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 245                 if ( $res === false )
 246                         return false;
 247                 if ( !$this->numRows( $res ) ) {
 248                         $this->freeResult($res);
 249                         return 0;
 250                 }
 251
 252                 $rows = 1;
 253                 while( $plan = $this->fetchObject( $res ) ) {
 254                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 255                 }
 256
 257                 $this->freeResult($res);
 258                 return $rows;
 259         }
 260
 261         function fieldInfo( $table, $field ) {
 262                 $table = $this->tableName( $table );
 263                 $res = $this->query( "SELECT * FROM $table LIMIT 1" );
 264                 $n = mysql_num_fields( $res->result );
 265                 for( $i = 0; $i < $n; $i++ ) {
 266                         $meta = mysql_fetch_field( $res->result, $i );
 267                         if( $field == $meta->name ) {
 268                                 return new MySQLField($meta);
 269                         }
 270                 }
 271                 return false;
 272         }
 273
 274         function selectDB( $db ) {
 275                 $this->mDBname = $db;
 276                 return mysql_select_db( $db, $this->mConn );
 277         }
 278
 279         function strencode( $s ) {
 280                 return mysql_real_escape_string( $s, $this->mConn );
 281         }
 282
 283         function ping() {
 284                 if( !function_exists( 'mysql_ping' ) ) {
 285                         wfDebug( "Tried to call mysql_ping but this is ancient PHP version. Faking it!\n" );
 286                         return true;
 287                 }
 288                 $ping = mysql_ping( $this->mConn );
 289                 if ( $ping ) {
 290                         return true;
 291                 }
 292
 293                 // Need to reconnect manually in MySQL client 5.0.13+
 294                 if ( version_compare( mysql_get_client_info(), '5.0.13', '>=' ) ) {
 295                         mysql_close( $this->mConn );
 296                         $this->mOpened = false;
 297                         $this->mConn = false;
 298                         $this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
 299                         return true;
 300                 }
 301                 return false;
 302         }
 303
 304         function getServerVersion() {
 305                 return mysql_get_server_info( $this->mConn );
 306         }
 307
 308         function useIndexClause( $index ) {
 309                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 310         }
 311
 312         function lowPriorityOption() {
 313                 return 'LOW_PRIORITY';
 314         }
 315
 316         function getSoftwareLink() {
 317                 return '[http://www.mysql.com/ MySQL]';
 318         }
 319
 320         function standardSelectDistinct() {
 321                 return false;
 322         }
 323
 324         public function setTimeout( $timeout ) {
 325                 $this->query( "SET net_read_timeout=$timeout" );
 326                 $this->query( "SET net_write_timeout=$timeout" );
 327         }
 328
 329         public function lock( $lockName, $method, $timeout = 5 ) {
 330                 $lockName = $this->addQuotes( $lockName );
 331                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 332                 $row = $this->fetchObject( $result );
 333                 $this->freeResult( $result );
 334
 335                 if( $row->lockstatus == 1 ) {
 336                         return true;
 337                 } else {
 338                         wfDebug( __METHOD__." failed to acquire lock\n" );
 339                         return false;
 340                 }
 341         }
 342
 343         public function unlock( $lockName, $method ) {
 344                 $lockName = $this->addQuotes( $lockName );
 345                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 346                 $row = $this->fetchObject( $result );
 347                 return $row->lockstatus;
 348         }
 349
 350         public function lockTables( $read, $write, $method, $lowPriority = true ) {
 351                 $items = array();
 352
 353                 foreach( $write as $table ) {
 354                         $tbl = $this->tableName( $table ) .
 355                                         ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
 356                                         ' WRITE';
 357                         $items[] = $tbl;
 358                 }
 359                 foreach( $read as $table ) {
 360                         $items[] = $this->tableName( $table ) . ' READ';
 361                 }
 362                 $sql = "LOCK TABLES " . implode( ',', $items );
 363                 $this->query( $sql, $method );
 364         }
 365
 366         public function unlockTables( $method ) {
 367                 $this->query( "UNLOCK TABLES", $method );
 368         }
 369
 370         public function setBigSelects( $value = true ) {
 371                 if ( $value === 'default' ) {
 372                         if ( $this->mDefaultBigSelects === null ) {
 373                                 # Function hasn't been called before so it must already be set to the default
 374                                 return;
 375                         } else {
 376                                 $value = $this->mDefaultBigSelects;
 377                         }
 378                 } elseif ( $this->mDefaultBigSelects === null ) {
 379                         $this->mDefaultBigSelects = (bool)$this->selectField( false, '@@sql_big_selects' );
 380                 }
 381                 $encValue = $value ? '1' : '0';
 382                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
 383         }
 384
 385
 386         /**
 387          * Determines if the last failure was due to a deadlock
 388          */
 389         function wasDeadlock() {
 390                 return $this->lastErrno() == 1213;
 391         }
 392
 393         /**
 394          * Determines if the last query error was something that should be dealt
 395          * with by pinging the connection and reissuing the query
 396          */
 397         function wasErrorReissuable() {
 398                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
 399         }
 400
 401         /**
 402          * Determines if the last failure was due to the database being read-only.
 403          */
 404         function wasReadOnlyError() {
 405                 return $this->lastErrno() == 1223 ||
 406                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
 407         }
 408
 409         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabaseMysql::duplicateTableStructure' ) {
 410                 $tmp = $temporary ? 'TEMPORARY ' : '';
 411                 if ( strcmp( $this->getServerVersion(), '4.1' ) < 0 ) {
 412                         # Hack for MySQL versions < 4.1, which don't support
 413                         # "CREATE TABLE ... LIKE". Note that
 414                         # "CREATE TEMPORARY TABLE ... SELECT * FROM ... LIMIT 0"
 415                         # would not create the indexes we need....
 416                         #
 417                         # Note that we don't bother changing around the prefixes here be-
 418                         # cause we know we're using MySQL anyway.
 419
 420                         $res = $this->query( "SHOW CREATE TABLE $oldName" );
 421                         $row = $this->fetchRow( $res );
 422                         $oldQuery = $row[1];
 423                         $query = preg_replace( '/CREATE TABLE `(.*?)`/',
 424                                 "CREATE $tmp TABLE `$newName`", $oldQuery );
 425                         if ($oldQuery === $query) {
 426                                 # Couldn't do replacement
 427                                 throw new MWException( "could not create temporary table $newName" );
 428                         }
 429                 } else {
 430                         $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
 431                 }
 432                 $this->query( $query, $fname );
 433         }
 434
 435 }
 436
 437 /**
 438  * Legacy support: Database == DatabaseMysql
 439  */
 440 class Database extends DatabaseMysql {}
 441
 442 class MySQLMasterPos {
 443         var $file, $pos;
 444
 445         function __construct( $file, $pos ) {
 446                 $this->file = $file;
 447                 $this->pos = $pos;
 448         }
 449
 450         function __toString() {
 451                 return "{$this->file}/{$this->pos}";
 452         }
 453 }