protected $mConn = null;
protected $mOpened = false;
- /** @var Array */
+ /**
+ * @since 1.20
+ * @var array of callable
+ */
protected $trxIdleCallbacks = array();
protected $mTablePrefix;
protected $delimiter = ';';
+ /**
+ * Remembers the function name given for starting the most recent transaction via begin().
+ * Used to provide additional context for error reporting.
+ *
+ * @var String
+ * @see DatabaseBase::mTrxLevel
+ */
+ private $mTrxFname = null;
+
+ /**
+ * Record if possible write queries were done in the last transaction started
+ *
+ * @var Bool
+ * @see DatabaseBase::mTrxLevel
+ */
+ private $mTrxDoneWrites = false;
+
+ /**
+ * Record if the current transaction was started implicitly due to DBO_TRX being set.
+ *
+ * @var Bool
+ * @see DatabaseBase::mTrxLevel
+ */
+ private $mTrxAutomatic = false;
+
# ------------------------------------------------------------------------------
# Accessors
# ------------------------------------------------------------------------------
$this->mOpened = false;
if ( $this->mConn ) {
if ( $this->trxLevel() ) {
- $this->commit( __METHOD__ );
+ if ( !$this->mTrxAutomatic ) {
+ wfWarn( "Transaction still in progress (from {$this->mTrxFname}), " .
+ " performing implicit commit before closing connection!" );
+ }
+
+ $this->commit( __METHOD__, true );
}
+
$ret = $this->closeConnection();
$this->mConn = false;
return $ret;
/**
* @param $error String: fallback error message, used if none is given by DB
+ * @throws DBConnectionError
*/
function reportConnectionError( $error = 'Unknown error' ) {
$myError = $this->lastError();
* comment (you can use __METHOD__ or add some extra info)
* @param $tempIgnore Boolean: Whether to avoid throwing an exception on errors...
* maybe best to catch the exception instead?
+ * @throws MWException
* @return boolean|ResultWrapper. true for a successful write query, ResultWrapper object
* for a successful read query, or false on failure if $tempIgnore set
- * @throws DBQueryError Thrown when the database returns an error of any kind
*/
public function query( $sql, $fname = '', $tempIgnore = false ) {
$isMaster = !is_null( $this->getLBInfo( 'master' ) );
$commentedSql = preg_replace( '/\s/', " /* $fname $userName */ ", $sql, 1 );
# If DBO_TRX is set, start a transaction
- if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() &&
- $sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK' ) {
- # avoid establishing transactions for SHOW and SET statements too -
+ if ( ( $this->mFlags & DBO_TRX ) && !$this->mTrxLevel &&
+ $sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK' )
+ {
+ # Avoid establishing transactions for SHOW and SET statements too -
# that would delay transaction initializations to once connection
# is really used by application
$sqlstart = substr( $sql, 0, 10 ); // very much worth it, benchmark certified(tm)
wfDebug("Implicit transaction start.\n");
}
$this->begin( __METHOD__ . " ($fname)" );
+ $this->mTrxAutomatic = true;
}
}
+ # Keep track of whether the transaction has write queries pending
+ if ( $this->mTrxLevel && !$this->mTrxDoneWrites && $this->isWriteQuery( $sql ) ) {
+ $this->mTrxDoneWrites = true;
+ }
+
if ( $this->debug() ) {
static $cnt = 0;
if ( false === $ret && $this->wasErrorReissuable() ) {
# Transaction is gone, like it or not
$this->mTrxLevel = 0;
+ $this->trxIdleCallbacks = array(); // cancel
wfDebug( "Connection lost, reconnecting...\n" );
if ( $this->ping() ) {
* @param $sql String
* @param $fname String
* @param $tempIgnore Boolean
+ * @throws DBQueryError
*/
public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
# Ignore errors during error handling to avoid infinite recursion
* while we're doing this.
*
* @param $matches Array
+ * @throws DBUnexpectedError
* @return String
*/
protected function fillPreparedArg( $matches ) {
/**
* Makes an encoded list of strings from an array
* @param $a Array containing the data
- * @param $mode int Constant
+ * @param int $mode Constant
* - LIST_COMMA: comma separated, no field names
* - LIST_AND: ANDed WHERE clause (without the WHERE). See
* the documentation for $conds in DatabaseBase::select().
* - LIST_SET: comma separated with field names, like a SET clause
* - LIST_NAMES: comma separated field names
*
+ * @throws MWException|DBUnexpectedError
* @return string
*/
public function makeList( $a, $mode = LIST_COMMA ) {
* ANDed together in the WHERE clause
* @param $fname String: Calling function name (use __METHOD__) for
* logs/profiling
+ * @throws DBUnexpectedError
*/
public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
$fname = 'DatabaseBase::deleteJoin' )
* the format. Use $conds == "*" to delete all rows
* @param $fname String name of the calling function
*
+ * @throws DBUnexpectedError
* @return bool
*/
public function delete( $table, $conds, $fname = 'DatabaseBase::delete' ) {
* @param $limit Integer the SQL limit
* @param $offset Integer|bool the SQL offset (default false)
*
+ * @throws DBUnexpectedError
* @return string
*/
public function limitResult( $sql, $limit, $offset = false ) {
*
* This is useful for updates to different systems or separate transactions are needed.
*
+ * @since 1.20
+ *
* @param Closure $callback
- * @return void
*/
final public function onTransactionIdle( Closure $callback ) {
if ( $this->mTrxLevel ) {
}
/**
- * Actually run the "on transaction idle" callbacks
+ * Actually run the "on transaction idle" callbacks.
+ *
+ * @since 1.20
*/
protected function runOnTransactionIdleCallbacks() {
$e = null; // last exception
}
/**
- * Begin a transaction
+ * Begin a transaction. If a transaction is already in progress, that transaction will be committed before the
+ * new transaction is started.
+ *
+ * Note that when the DBO_TRX flag is set (which is usually the case for web requests, but not for maintenance scripts),
+ * any previous database query will have started a transaction automatically.
+ *
+ * Nesting of transactions is not supported. Attempts to nest transactions will cause a warning, unless the current
+ * transaction was started automatically because of the DBO_TRX flag.
*
* @param $fname string
*/
final public function begin( $fname = 'DatabaseBase::begin' ) {
+ global $wgDebugDBTransactions;
+
if ( $this->mTrxLevel ) { // implicit commit
+ if ( !$this->mTrxAutomatic ) {
+ // We want to warn about inadvertently nested begin/commit pairs, but not about auto-committing
+ // implicit transactions that were started by query() because DBO_TRX was set.
+
+ wfWarn( "$fname: Transaction already in progress (from {$this->mTrxFname}), " .
+ " performing implicit commit!" );
+ } else {
+ // if the transaction was automatic and has done write operations,
+ // log it if $wgDebugDBTransactions is enabled.
+
+ if ( $this->mTrxDoneWrites && $wgDebugDBTransactions ) {
+ wfDebug( "$fname: Automatic transaction with writes in progress (from {$this->mTrxFname}), " .
+ " performing implicit commit!\n" );
+ }
+ }
+
$this->doCommit( $fname );
$this->runOnTransactionIdleCallbacks();
}
+
$this->doBegin( $fname );
+ $this->mTrxFname = $fname;
+ $this->mTrxDoneWrites = false;
+ $this->mTrxAutomatic = false;
}
/**
+ * Issues the BEGIN command to the database server.
+ *
* @see DatabaseBase::begin()
* @param type $fname
*/
}
/**
- * End a transaction
+ * Commits a transaction previously started using begin().
+ * If no transaction is in progress, a warning is issued.
+ *
+ * Nesting of transactions is not supported.
*
* @param $fname string
- */
- final public function commit( $fname = 'DatabaseBase::commit' ) {
+ * @param $suppressWarnings bool Suppress any warnings about open transactions (default_ false).
+ * Only set this if you are absolutely sure that it is safe to ignore these warnings in your context.
+ */
+ final public function commit( $fname = 'DatabaseBase::commit', $suppressWarnings = false ) {
+ if ( !$suppressWarnings ) {
+ if ( !$this->mTrxLevel ) {
+ wfWarn( "$fname: No transaction to commit, something got out of sync!" );
+ } elseif( $this->mTrxAutomatic ) {
+ wfWarn( "$fname: Explicit commit of implicit transaction. Something may be out of sync!" );
+ }
+ }
+
$this->doCommit( $fname );
$this->runOnTransactionIdleCallbacks();
}
/**
+ * Issues the COMMIT command to the database server.
+ *
* @see DatabaseBase::commit()
* @param type $fname
*/
}
/**
- * Rollback a transaction.
+ * Rollback a transaction previously started using begin().
+ * If no transaction is in progress, a warning is issued.
+ *
* No-op on non-transactional databases.
*
* @param $fname string
*/
final public function rollback( $fname = 'DatabaseBase::rollback' ) {
+ if ( !$this->mTrxLevel ) {
+ wfWarn( "$fname: No transaction to rollback, something got out of sync!" );
+ }
$this->doRollback( $fname );
$this->trxIdleCallbacks = array(); // cancel
}
/**
+ * Issues the ROLLBACK command to the database server.
+ *
* @see DatabaseBase::rollback()
* @param type $fname
*/
* @param $newName String: name of table to be created
* @param $temporary Boolean: whether the new table should be temporary
* @param $fname String: calling function name
+ * @throws MWException
* @return Boolean: true if operation was successful
*/
public function duplicateTableStructure( $oldName, $newName, $temporary = false,
*
* @param $prefix string Only show tables with this prefix, e.g. mw_
* @param $fname String: calling function name
+ * @throws MWException
*/
function listTables( $prefix = null, $fname = 'DatabaseBase::listTables' ) {
throw new MWException( 'DatabaseBase::listTables is not implemented in descendant class' );
* on object's error ignore settings).
*
* @param $filename String: File name to open
- * @param $lineCallback Callback: Optional function called before reading each line
- * @param $resultCallback Callback: Optional function called for each MySQL result
- * @param $fname String: Calling function name or false if name should be
+ * @param bool|callable $lineCallback Optional function called before reading each line
+ * @param bool|callable $resultCallback Optional function called for each MySQL result
+ * @param bool|string $fname Calling function name or false if name should be
* generated dynamically using $filename
+ * @throws MWException
* @return bool|string
*/
public function sourceFile(