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                 wfDl( 'mysql' );
  30
  31                 # Fail now
  32                 # Otherwise we get a suppressed fatal error, which is very hard to track down
  33                 if ( !function_exists( 'mysql_connect' ) ) {
  34                         throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
  35                 }
  36
  37                 # Debugging hack -- fake cluster
  38                 if ( $wgAllDBsAreLocalhost ) {
  39                         $realServer = 'localhost';
  40                 } else {
  41                         $realServer = $server;
  42                 }
  43                 $this->close();
  44                 $this->mServer = $server;
  45                 $this->mUser = $user;
  46                 $this->mPassword = $password;
  47                 $this->mDBname = $dbName;
  48
  49                 $success = false;
  50
  51                 wfProfileIn("dbconnect-$server");
  52
  53                 # The kernel's default SYN retransmission period is far too slow for us,
  54                 # so we use a short timeout plus a manual retry. Retrying means that a small
  55                 # but finite rate of SYN packet loss won't cause user-visible errors.
  56                 $this->mConn = false;
  57                 if ( ini_get( 'mysql.connect_timeout' ) <= 3 ) {
  58                         $numAttempts = 2;
  59                 } else {
  60                         $numAttempts = 1;
  61                 }
  62                 $this->installErrorHandler();
  63                 for ( $i = 0; $i < $numAttempts && !$this->mConn; $i++ ) {
  64                         if ( $i > 1 ) {
  65                                 usleep( 1000 );
  66                         }
  67                         if ( $this->mFlags & DBO_PERSISTENT ) {
  68                                 $this->mConn = mysql_pconnect( $realServer, $user, $password );
  69                         } else {
  70                                 # Create a new connection...
  71                                 $this->mConn = mysql_connect( $realServer, $user, $password, true );
  72                         }
  73                         if ($this->mConn === false) {
  74                                 #$iplus = $i + 1;
  75                                 #wfLogDBError("Connect loop error $iplus of $max ($server): " . mysql_errno() . " - " . mysql_error()."\n");
  76                         }
  77                 }
  78                 $phpError = $this->restoreErrorHandler();
  79                 # Always log connection errors
  80                 if ( !$this->mConn ) {
  81                         $error = $this->lastError();
  82                         if ( !$error ) {
  83                                 $error = $phpError;
  84                         }
  85                         wfLogDBError( "Error connecting to {$this->mServer}: $error\n" );
  86                         wfDebug( "DB connection error\n" );
  87                         wfDebug( "Server: $server, User: $user, Password: " .
  88                                 substr( $password, 0, 3 ) . "..., error: " . mysql_error() . "\n" );
  89                         $success = false;
  90                 }
  91
  92                 wfProfileOut("dbconnect-$server");
  93
  94                 if ( $dbName != '' && $this->mConn !== false ) {
  95                         $success = @/**/mysql_select_db( $dbName, $this->mConn );
  96                         if ( !$success ) {
  97                                 $error = "Error selecting database $dbName on server {$this->mServer} " .
  98                                         "from client host " . wfHostname() . "\n";
  99                                 wfLogDBError(" Error selecting database $dbName on server {$this->mServer} \n");
 100                                 wfDebug( $error );
 101                         }
 102                 } else {
 103                         # Delay USE query
 104                         $success = (bool)$this->mConn;
 105                 }
 106
 107                 if ( $success ) {
 108                         $version = $this->getServerVersion();
 109                         if ( version_compare( $version, '4.1' ) >= 0 ) {
 110                                 // Tell the server we're communicating with it in UTF-8.
 111                                 // This may engage various charset conversions.
 112                                 global $wgDBmysql5;
 113                                 if( $wgDBmysql5 ) {
 114                                         $this->query( 'SET NAMES utf8', __METHOD__ );
 115                                 }
 116                                 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
 117                                 if (is_string($wgSQLMode)) {
 118                                         $this->query( "SET sql_mode = '$wgSQLMode'", __METHOD__ );
 119                                 }
 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                 $sQuoted = mysql_real_escape_string( $s, $this->mConn );
 281
 282                 if($sQuoted === false) {
 283                         $this->ping();
 284                         $sQuoted = mysql_real_escape_string( $s, $this->mConn );
 285                 }
 286                 return $sQuoted;
 287         }
 288
 289         function ping() {
 290                 $ping = mysql_ping( $this->mConn );
 291                 if ( $ping ) {
 292                         return true;
 293                 }
 294
 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
 302         function getServerVersion() {
 303                 return mysql_get_server_info( $this->mConn );
 304         }
 305
 306         function useIndexClause( $index ) {
 307                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 308         }
 309
 310         function lowPriorityOption() {
 311                 return 'LOW_PRIORITY';
 312         }
 313
 314         function getSoftwareLink() {
 315                 return '[http://www.mysql.com/ MySQL]';
 316         }
 317
 318         function standardSelectDistinct() {
 319                 return false;
 320         }
 321
 322         public function setTimeout( $timeout ) {
 323                 $this->query( "SET net_read_timeout=$timeout" );
 324                 $this->query( "SET net_write_timeout=$timeout" );
 325         }
 326
 327         public function lock( $lockName, $method, $timeout = 5 ) {
 328                 $lockName = $this->addQuotes( $lockName );
 329                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 330                 $row = $this->fetchObject( $result );
 331                 $this->freeResult( $result );
 332
 333                 if( $row->lockstatus == 1 ) {
 334                         return true;
 335                 } else {
 336                         wfDebug( __METHOD__." failed to acquire lock\n" );
 337                         return false;
 338                 }
 339         }
 340
 341         public function unlock( $lockName, $method ) {
 342                 $lockName = $this->addQuotes( $lockName );
 343                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 344                 $row = $this->fetchObject( $result );
 345                 return $row->lockstatus;
 346         }
 347
 348         public function lockTables( $read, $write, $method, $lowPriority = true ) {
 349                 $items = array();
 350
 351                 foreach( $write as $table ) {
 352                         $tbl = $this->tableName( $table ) .
 353                                         ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
 354                                         ' WRITE';
 355                         $items[] = $tbl;
 356                 }
 357                 foreach( $read as $table ) {
 358                         $items[] = $this->tableName( $table ) . ' READ';
 359                 }
 360                 $sql = "LOCK TABLES " . implode( ',', $items );
 361                 $this->query( $sql, $method );
 362         }
 363
 364         public function unlockTables( $method ) {
 365                 $this->query( "UNLOCK TABLES", $method );
 366         }
 367
 368         public function setBigSelects( $value = true ) {
 369                 if ( $value === 'default' ) {
 370                         if ( $this->mDefaultBigSelects === null ) {
 371                                 # Function hasn't been called before so it must already be set to the default
 372                                 return;
 373                         } else {
 374                                 $value = $this->mDefaultBigSelects;
 375                         }
 376                 } elseif ( $this->mDefaultBigSelects === null ) {
 377                         $this->mDefaultBigSelects = (bool)$this->selectField( false, '@@sql_big_selects' );
 378                 }
 379                 $encValue = $value ? '1' : '0';
 380                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
 381         }
 382
 383
 384         /**
 385          * Determines if the last failure was due to a deadlock
 386          */
 387         function wasDeadlock() {
 388                 return $this->lastErrno() == 1213;
 389         }
 390
 391         /**
 392          * Determines if the last query error was something that should be dealt
 393          * with by pinging the connection and reissuing the query
 394          */
 395         function wasErrorReissuable() {
 396                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
 397         }
 398
 399         /**
 400          * Determines if the last failure was due to the database being read-only.
 401          */
 402         function wasReadOnlyError() {
 403                 return $this->lastErrno() == 1223 ||
 404                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
 405         }
 406
 407         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = 'DatabaseMysql::duplicateTableStructure' ) {
 408                 $tmp = $temporary ? 'TEMPORARY ' : '';
 409                 if ( strcmp( $this->getServerVersion(), '4.1' ) < 0 ) {
 410                         # Hack for MySQL versions < 4.1, which don't support
 411                         # "CREATE TABLE ... LIKE". Note that
 412                         # "CREATE TEMPORARY TABLE ... SELECT * FROM ... LIMIT 0"
 413                         # would not create the indexes we need....
 414                         #
 415                         # Note that we don't bother changing around the prefixes here be-
 416                         # cause we know we're using MySQL anyway.
 417
 418                         $res = $this->query( "SHOW CREATE TABLE $oldName" );
 419                         $row = $this->fetchRow( $res );
 420                         $oldQuery = $row[1];
 421                         $query = preg_replace( '/CREATE TABLE `(.*?)`/',
 422                                 "CREATE $tmp TABLE `$newName`", $oldQuery );
 423                         if ($oldQuery === $query) {
 424                                 # Couldn't do replacement
 425                                 throw new MWException( "could not create temporary table $newName" );
 426                         }
 427                 } else {
 428                         $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
 429                 }
 430                 $this->query( $query, $fname );
 431         }
 432
 433 }
 434
 435 /**
 436  * Legacy support: Database == DatabaseMysql
 437  */
 438 class Database extends DatabaseMysql {}
 439
 440 class MySQLMasterPos {
 441         var $file, $pos;
 442
 443         function __construct( $file, $pos ) {
 444                 $this->file = $file;
 445                 $this->pos = $pos;
 446         }
 447
 448         function __toString() {
 449                 return "{$this->file}/{$this->pos}";
 450         }
 451 }