Update to MediaWiki 1.20.2

this update includes:
* adjusted Arch Linux skin
* updated FluxBBAuthPlugin
* patch for https://bugzilla.wikimedia.org/show_bug.cgi?id=44024

1 files changed, 387 insertions, 314 deletions

diff --git a/includes/db/Database.php b/includes/db/Database.php
index f3e84675..5f10b97d 100644
--- a/includes/db/Database.php
+++ b/includes/db/Database.php
@@ -2,10 +2,26 @@
 /**
  * @defgroup Database Database
  *
+ * This file deals with database interface functions
+ * and query specifics/optimisations.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
  * @file
  * @ingroup Database
- * This file deals with database interface functions
- * and query specifics/optimisations
  */
 
 /** Number of times to re-try an operation in case of deadlock */
@@ -209,12 +225,15 @@ abstract class DatabaseBase implements DatabaseType {
 
 	protected $mServer, $mUser, $mPassword, $mDBname;
 
-	/**
-	 * @var DatabaseBase
-	 */
 	protected $mConn = null;
 	protected $mOpened = false;
 
+	/**
+	 * @since 1.20
+	 * @var array of Closure
+	 */
+	protected $mTrxIdleCallbacks = array();
+
 	protected $mTablePrefix;
 	protected $mFlags;
 	protected $mTrxLevel = 0;
@@ -253,9 +272,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 *   - false to disable debugging
 	 *   - omitted or null to do nothing
 	 *
-	 * @return The previous value of the flag
+	 * @return bool|null previous value of the flag
 	 */
-	function debug( $debug = null ) {
+	public function debug( $debug = null ) {
 		return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
 	}
 
@@ -279,9 +298,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @param $buffer null|bool
 	 *
-	 * @return The previous value of the flag
+	 * @return null|bool The previous value of the flag
 	 */
-	function bufferResults( $buffer = null ) {
+	public function bufferResults( $buffer = null ) {
 		if ( is_null( $buffer ) ) {
 			return !(bool)( $this->mFlags & DBO_NOBUFFER );
 		} else {
@@ -300,7 +319,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool The previous value of the flag.
 	 */
-	function ignoreErrors( $ignoreErrors = null ) {
+	public function ignoreErrors( $ignoreErrors = null ) {
 		return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors );
 	}
 
@@ -310,28 +329,28 @@ abstract class DatabaseBase implements DatabaseType {
 	 * Historically, transactions were allowed to be "nested". This is no
 	 * longer supported, so this function really only returns a boolean.
 	 *
-	 * @param $level An integer (0 or 1), or omitted to leave it unchanged.
-	 * @return The previous value
+	 * @param $level int An integer (0 or 1), or omitted to leave it unchanged.
+	 * @return int The previous value
 	 */
-	function trxLevel( $level = null ) {
+	public function trxLevel( $level = null ) {
 		return wfSetVar( $this->mTrxLevel, $level );
 	}
 
 	/**
 	 * Get/set the number of errors logged. Only useful when errors are ignored
-	 * @param $count The count to set, or omitted to leave it unchanged.
-	 * @return The error count
+	 * @param $count int The count to set, or omitted to leave it unchanged.
+	 * @return int The error count
 	 */
-	function errorCount( $count = null ) {
+	public function errorCount( $count = null ) {
 		return wfSetVar( $this->mErrorCount, $count );
 	}
 
 	/**
 	 * Get/set the table prefix.
-	 * @param $prefix The table prefix to set, or omitted to leave it unchanged.
-	 * @return The previous table prefix.
+	 * @param $prefix string The table prefix to set, or omitted to leave it unchanged.
+	 * @return string The previous table prefix.
 	 */
-	function tablePrefix( $prefix = null ) {
+	public function tablePrefix( $prefix = null ) {
 		return wfSetVar( $this->mTablePrefix, $prefix );
 	}
 
@@ -344,7 +363,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return LoadBalancer|null
 	 */
-	function getLBInfo( $name = null ) {
+	public function getLBInfo( $name = null ) {
 		if ( is_null( $name ) ) {
 			return $this->mLBInfo;
 		} else {
@@ -364,7 +383,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $name
 	 * @param $value
 	 */
-	function setLBInfo( $name, $value = null ) {
+	public function setLBInfo( $name, $value = null ) {
 		if ( is_null( $value ) ) {
 			$this->mLBInfo = $name;
 		} else {
@@ -377,7 +396,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @param $lag int
 	 */
-	function setFakeSlaveLag( $lag ) {
+	public function setFakeSlaveLag( $lag ) {
 		$this->mFakeSlaveLag = $lag;
 	}
 
@@ -386,7 +405,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @param $enabled bool
 	 */
-	function setFakeMaster( $enabled = true ) {
+	public function setFakeMaster( $enabled = true ) {
 		$this->mFakeMaster = $enabled;
 	}
 
@@ -395,7 +414,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function cascadingDeletes() {
+	public function cascadingDeletes() {
 		return false;
 	}
 
@@ -404,7 +423,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function cleanupTriggers() {
+	public function cleanupTriggers() {
 		return false;
 	}
 
@@ -414,7 +433,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function strictIPs() {
+	public function strictIPs() {
 		return false;
 	}
 
@@ -423,7 +442,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	*/
-	function realTimestamps() {
+	public function realTimestamps() {
 		return false;
 	}
 
@@ -432,7 +451,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function implicitGroupby() {
+	public function implicitGroupby() {
 		return true;
 	}
 
@@ -442,17 +461,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function implicitOrderby() {
-		return true;
-	}
-
-	/**
-	 * Returns true if this database requires that SELECT DISTINCT queries require that all
-	   ORDER BY expressions occur in the SELECT list per the SQL92 standard
-	 *
-	 * @return bool
-	 */
-	function standardSelectDistinct() {
+	public function implicitOrderby() {
 		return true;
 	}
 
@@ -462,7 +471,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function searchableIPs() {
+	public function searchableIPs() {
 		return false;
 	}
 
@@ -471,7 +480,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function functionalIndexes() {
+	public function functionalIndexes() {
 		return false;
 	}
 
@@ -479,7 +488,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * Return the last query that went through DatabaseBase::query()
 	 * @return String
 	 */
-	function lastQuery() {
+	public function lastQuery() {
 		return $this->mLastQuery;
 	}
 
@@ -489,15 +498,25 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function doneWrites() {
+	public function doneWrites() {
 		return $this->mDoneWrites;
 	}
 
 	/**
+	 * Returns true if there is a transaction open with possible write
+	 * queries or transaction idle callbacks waiting on it to finish.
+	 *
+	 * @return bool
+	 */
+	public function writesOrCallbacksPending() {
+		return $this->mTrxLevel && ( $this->mDoneWrites || $this->mTrxIdleCallbacks );
+	}
+
+	/**
 	 * Is a connection to the database open?
 	 * @return Boolean
 	 */
-	function isOpen() {
+	public function isOpen() {
 		return $this->mOpened;
 	}
 
@@ -513,8 +532,12 @@ abstract class DatabaseBase implements DatabaseType {
 	 *       and removes it in command line mode
 	 *   - DBO_PERSISTENT: use persistant database connection
 	 */
-	function setFlag( $flag ) {
+	public function setFlag( $flag ) {
+		global $wgDebugDBTransactions;
 		$this->mFlags |= $flag;
+		if ( ( $flag & DBO_TRX) & $wgDebugDBTransactions ) {
+			wfDebug("Implicit transactions are now  disabled.\n");
+		}
 	}
 
 	/**
@@ -522,8 +545,12 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @param $flag: same as setFlag()'s $flag param
 	 */
-	function clearFlag( $flag ) {
+	public function clearFlag( $flag ) {
+		global $wgDebugDBTransactions;
 		$this->mFlags &= ~$flag;
+		if ( ( $flag & DBO_TRX ) && $wgDebugDBTransactions ) {
+			wfDebug("Implicit transactions are now disabled.\n");
+		}
 	}
 
 	/**
@@ -532,7 +559,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $flag: same as setFlag()'s $flag param
 	 * @return Boolean
 	 */
-	function getFlag( $flag ) {
+	public function getFlag( $flag ) {
 		return !!( $this->mFlags & $flag );
 	}
 
@@ -543,14 +570,14 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return string
 	 */
-	function getProperty( $name ) {
+	public function getProperty( $name ) {
 		return $this->$name;
 	}
 
 	/**
 	 * @return string
 	 */
-	function getWikiID() {
+	public function getWikiID() {
 		if ( $this->mTablePrefix ) {
 			return "{$this->mDBname}-{$this->mTablePrefix}";
 		} else {
@@ -588,15 +615,21 @@ abstract class DatabaseBase implements DatabaseType {
 	function __construct( $server = false, $user = false, $password = false, $dbName = false,
 		$flags = 0, $tablePrefix = 'get from global'
 	) {
-		global $wgDBprefix, $wgCommandLineMode;
+		global $wgDBprefix, $wgCommandLineMode, $wgDebugDBTransactions;
 
 		$this->mFlags = $flags;
 
 		if ( $this->mFlags & DBO_DEFAULT ) {
 			if ( $wgCommandLineMode ) {
 				$this->mFlags &= ~DBO_TRX;
+				if ( $wgDebugDBTransactions ) {
+					wfDebug("Implicit transaction open disabled.\n");
+				}
 			} else {
 				$this->mFlags |= DBO_TRX;
+				if ( $wgDebugDBTransactions ) {
+					wfDebug("Implicit transaction open enabled.\n");
+				}
 			}
 		}
 
@@ -622,35 +655,6 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Same as new DatabaseMysql( ... ), kept for backward compatibility
-	 * @deprecated since 1.17
-	 *
-	 * @param $server
-	 * @param $user
-	 * @param $password
-	 * @param $dbName
-	 * @param $flags int
-	 * @return DatabaseMysql
-	 */
-	static function newFromParams( $server, $user, $password, $dbName, $flags = 0 ) {
-		wfDeprecated( __METHOD__, '1.17' );
-		return new DatabaseMysql( $server, $user, $password, $dbName, $flags );
-	}
-
-	/**
-	 * Same as new factory( ... ), kept for backward compatibility
-	 * @deprecated since 1.18
-	 * @see Database::factory()
-	 */
-	public final static function newFromType( $dbType, $p = array() ) {
-		wfDeprecated( __METHOD__, '1.18' );
-		if ( isset( $p['tableprefix'] ) ) {
-			$p['tablePrefix'] = $p['tableprefix'];
-		}
-		return self::factory( $dbType, $p );
-	}
-
-	/**
 	 * Given a DB type, construct the name of the appropriate child class of
 	 * DatabaseBase. This is designed to replace all of the manual stuff like:
 	 *	$class = 'Database' . ucfirst( strtolower( $type ) );
@@ -665,6 +669,8 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @see ForeignDBRepo::getMasterDB()
 	 * @see WebInstaller_DBConnect::execute()
 	 *
+	 * @since 1.18
+	 *
 	 * @param $dbType String A possible DB type
 	 * @param $p Array An array of options to pass to the constructor.
 	 *    Valid options are: host, user, password, dbname, flags, tablePrefix
@@ -707,7 +713,7 @@ abstract class DatabaseBase implements DatabaseType {
 		}
 		if ( $this->mPHPError ) {
 			$error = preg_replace( '!\[<a.*</a>\]!', '', $this->mPHPError );
-			$error = preg_replace( '!^.*?:(.*)$!', '$1', $error );
+			$error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
 			return $error;
 		} else {
 			return false;
@@ -728,12 +734,31 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return Bool operation success. true if already closed.
 	 */
-	function close() {
-		# Stub, should probably be overridden
-		return true;
+	public function close() {
+		if ( count( $this->mTrxIdleCallbacks ) ) { // sanity
+			throw new MWException( "Transaction idle callbacks still pending." );
+		}
+		$this->mOpened = false;
+		if ( $this->mConn ) {
+			if ( $this->trxLevel() ) {
+				$this->commit( __METHOD__ );
+			}
+			$ret = $this->closeConnection();
+			$this->mConn = false;
+			return $ret;
+		} else {
+			return true;
+		}
 	}
 
 	/**
+	 * Closes underlying database connection
+	 * @since 1.20
+	 * @return bool: Whether connection was closed successfully
+	 */
+	protected abstract function closeConnection();
+
+	/**
 	 * @param $error String: fallback error message, used if none is given by DB
 	 */
 	function reportConnectionError( $error = 'Unknown error' ) {
@@ -762,8 +787,8 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function isWriteQuery( $sql ) {
-		return !preg_match( '/^(?:SELECT|BEGIN|COMMIT|SET|SHOW|\(SELECT)\b/i', $sql );
+	public function isWriteQuery( $sql ) {
+		return !preg_match( '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SET|SHOW|EXPLAIN|\(SELECT)\b/i', $sql );
 	}
 
 	/**
@@ -833,8 +858,13 @@ abstract class DatabaseBase implements DatabaseType {
 			# 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)
-			if ( strpos( $sqlstart, "SHOW " ) !== 0 && strpos( $sqlstart, "SET " ) !== 0 )
+			if ( strpos( $sqlstart, "SHOW " ) !== 0 && strpos( $sqlstart, "SET " ) !== 0 ) {
+				global $wgDebugDBTransactions;
+				if ( $wgDebugDBTransactions ) {
+					wfDebug("Implicit transaction start.\n");
+				}
 				$this->begin( __METHOD__ . " ($fname)" );
+			}
 		}
 
 		if ( $this->debug() ) {
@@ -863,6 +893,7 @@ abstract class DatabaseBase implements DatabaseType {
 		if ( false === $ret && $this->wasErrorReissuable() ) {
 			# Transaction is gone, like it or not
 			$this->mTrxLevel = 0;
+			$this->mTrxIdleCallbacks = array(); // cancel
 			wfDebug( "Connection lost, reconnecting...\n" );
 
 			if ( $this->ping() ) {
@@ -903,7 +934,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $fname String
 	 * @param $tempIgnore Boolean
 	 */
-	function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
+	public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 		# Ignore errors during error handling to avoid infinite recursion
 		$ignore = $this->ignoreErrors( true );
 		++$this->mErrorCount;
@@ -928,16 +959,12 @@ abstract class DatabaseBase implements DatabaseType {
 	 * & = filename; reads the file and inserts as a blob
 	 *     (we don't use this though...)
 	 *
-	 * This function should not be used directly by new code outside of the
-	 * database classes. The query wrapper functions (select() etc.) should be
-	 * used instead.
-	 *
 	 * @param $sql string
 	 * @param $func string
 	 *
 	 * @return array
 	 */
-	function prepare( $sql, $func = 'DatabaseBase::prepare' ) {
+	protected function prepare( $sql, $func = 'DatabaseBase::prepare' ) {
 		/* MySQL doesn't support prepared statements (yet), so just
 		   pack up the query for reference. We'll manually replace
 		   the bits later. */
@@ -948,7 +975,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * Free a prepared query, generated by prepare().
 	 * @param $prepared
 	 */
-	function freePrepared( $prepared ) {
+	protected function freePrepared( $prepared ) {
 		/* No-op by default */
 	}
 
@@ -959,7 +986,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return ResultWrapper
 	 */
-	function execute( $prepared, $args = null ) {
+	public function execute( $prepared, $args = null ) {
 		if ( !is_array( $args ) ) {
 			# Pull the var args
 			$args = func_get_args();
@@ -972,41 +999,13 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Prepare & execute an SQL statement, quoting and inserting arguments
-	 * in the appropriate places.
+	 * For faking prepared SQL statements on DBs that don't support it directly.
 	 *
-	 * This function should not be used directly by new code outside of the
-	 * database classes. The query wrapper functions (select() etc.) should be
-	 * used instead.
-	 *
-	 * @param $query String
-	 * @param $args ...
-	 *
-	 * @return ResultWrapper
-	 */
-	function safeQuery( $query, $args = null ) {
-		$prepared = $this->prepare( $query, 'DatabaseBase::safeQuery' );
-
-		if ( !is_array( $args ) ) {
-			# Pull the var args
-			$args = func_get_args();
-			array_shift( $args );
-		}
-
-		$retval = $this->execute( $prepared, $args );
-		$this->freePrepared( $prepared );
-
-		return $retval;
-	}
-
-	/**
-	 * For faking prepared SQL statements on DBs that don't support
-	 * it directly.
 	 * @param $preparedQuery String: a 'preparable' SQL statement
 	 * @param $args Array of arguments to fill it with
 	 * @return string executable SQL
 	 */
-	function fillPrepared( $preparedQuery, $args ) {
+	public function fillPrepared( $preparedQuery, $args ) {
 		reset( $args );
 		$this->preparedArgs =& $args;
 
@@ -1022,7 +1021,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $matches Array
 	 * @return String
 	 */
-	function fillPreparedArg( $matches ) {
+	protected function fillPreparedArg( $matches ) {
 		switch( $matches[1] ) {
 			case '\\?': return '?';
 			case '\\!': return '!';
@@ -1049,32 +1048,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @param $res Mixed: A SQL result
 	 */
-	function freeResult( $res ) {
-	}
-
-	/**
-	 * Simple UPDATE wrapper.
-	 * Usually throws a DBQueryError on failure.
-	 * If errors are explicitly ignored, returns success
-	 *
-	 * This function exists for historical reasons, DatabaseBase::update() has a more standard
-	 * calling convention and feature set
-	 *
-	 * @param $table string
-	 * @param $var
-	 * @param $value
-	 * @param $cond
-	 * @param $fname string
-	 *
-	 * @return bool
-	 */
-	function set( $table, $var, $value, $cond, $fname = 'DatabaseBase::set' ) {
-		$table = $this->tableName( $table );
-		$sql = "UPDATE $table SET $var = '" .
-		  $this->strencode( $value ) . "' WHERE ($cond)";
-
-		return (bool)$this->query( $sql, $fname );
-	}
+	public function freeResult( $res ) {}
 
 	/**
 	 * A SELECT wrapper which returns a single field from a single result row.
@@ -1091,9 +1065,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $fname string The function name of the caller.
 	 * @param $options string|array The query options. See DatabaseBase::select() for details.
 	 *
-	 * @return false|mixed The value from the field, or false on failure.
+	 * @return bool|mixed The value from the field, or false on failure.
 	 */
-	function selectField( $table, $var, $cond = '', $fname = 'DatabaseBase::selectField',
+	public function selectField( $table, $var, $cond = '', $fname = 'DatabaseBase::selectField',
 		$options = array() )
 	{
 		if ( !is_array( $options ) ) {
@@ -1126,7 +1100,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @return Array
 	 * @see DatabaseBase::select()
 	 */
-	function makeSelectOptions( $options ) {
+	public function makeSelectOptions( $options ) {
 		$preLimitTail = $postLimitTail = '';
 		$startOpts = '';
 
@@ -1146,7 +1120,10 @@ abstract class DatabaseBase implements DatabaseType {
 		}
 
 		if ( isset( $options['HAVING'] ) ) {
-			$preLimitTail .= " HAVING {$options['HAVING']}";
+			$having = is_array( $options['HAVING'] )
+				? $this->makeList( $options['HAVING'], LIST_AND )
+				: $options['HAVING'];
+			$preLimitTail .= " HAVING {$having}";
 		}
 
 		if ( isset( $options['ORDER BY'] ) ) {
@@ -1245,10 +1222,12 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $vars string|array
 	 *
 	 * May be either a field name or an array of field names. The field names
-	 * here are complete fragments of SQL, for direct inclusion into the SELECT
-	 * query. Expressions and aliases may be specified as in SQL, for example:
+	 * can be complete fragments of SQL, for direct inclusion into the SELECT
+	 * query. If an array is given, field aliases can be specified, for example:
+	 *
+	 *   array( 'maxrev' => 'MAX(rev_id)' )
 	 *
-	 *   array( 'MAX(rev_id) AS maxrev' )
+	 * This includes an expression with the alias "maxrev" in the query.
 	 *
 	 * If an expression is given, care must be taken to ensure that it is
 	 * DBMS-independent.
@@ -1305,7 +1284,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 *   - GROUP BY: May be either an SQL fragment string naming a field or
 	 *     expression to group by, or an array of such SQL fragments.
 	 *
-	 *   - HAVING: A string containing a HAVING clause.
+	 *   - HAVING: May be either an string containing a HAVING clause or an array of
+	 *     conditions building the HAVING clause. If an array is given, the conditions
+	 *     constructed from each element are combined with AND.
 	 *
 	 *   - ORDER BY: May be either an SQL fragment giving a field name or
 	 *     expression to order by, or an array of such SQL fragments.
@@ -1351,7 +1332,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *   DBQueryError exception will be thrown, except if the "ignore errors"
 	 *   option was set, in which case false will be returned.
 	 */
-	function select( $table, $vars, $conds = '', $fname = 'DatabaseBase::select',
+	public function select( $table, $vars, $conds = '', $fname = 'DatabaseBase::select',
 		$options = array(), $join_conds = array() ) {
 		$sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
 
@@ -1360,7 +1341,9 @@ abstract class DatabaseBase implements DatabaseType {
 
 	/**
 	 * The equivalent of DatabaseBase::select() except that the constructed SQL
-	 * is returned, instead of being immediately executed.
+	 * is returned, instead of being immediately executed. This can be useful for
+	 * doing UNION queries, where the SQL text of each query is needed. In general,
+	 * however, callers outside of Database classes should just use select().
 	 *
 	 * @param $table string|array Table name
 	 * @param $vars string|array Field names
@@ -1369,12 +1352,14 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $options string|array Query options
 	 * @param $join_conds string|array Join conditions
 	 *
-	 * @return SQL query string.
+	 * @return string SQL query string.
 	 * @see DatabaseBase::select()
 	 */
-	function selectSQLText( $table, $vars, $conds = '', $fname = 'DatabaseBase::select', $options = array(), $join_conds = array() ) {
+	public function selectSQLText( $table, $vars, $conds = '', $fname = 'DatabaseBase::select',
+		$options = array(), $join_conds = array() )
+	{
 		if ( is_array( $vars ) ) {
-			$vars = implode( ',', $vars );
+			$vars = implode( ',', $this->fieldNamesWithAlias( $vars ) );
 		}
 
 		$options = (array)$options;
@@ -1435,9 +1420,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $options string|array Query options
 	 * @param $join_conds array|string Join conditions
 	 *
-	 * @return ResultWrapper|bool
+	 * @return object|bool
 	 */
-	function selectRow( $table, $vars, $conds, $fname = 'DatabaseBase::selectRow',
+	public function selectRow( $table, $vars, $conds, $fname = 'DatabaseBase::selectRow',
 		$options = array(), $join_conds = array() )
 	{
 		$options = (array)$options;
@@ -1481,7 +1466,7 @@ abstract class DatabaseBase implements DatabaseType {
 		$fname = 'DatabaseBase::estimateRowCount', $options = array() )
 	{
 		$rows = 0;
-		$res = $this->select ( $table, 'COUNT(*) AS rowcount', $conds, $fname, $options );
+		$res = $this->select( $table, array( 'rowcount' => 'COUNT(*)' ), $conds, $fname, $options );
 
 		if ( $res ) {
 			$row = $this->fetchRow( $res );
@@ -1527,7 +1512,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $fname String: calling function name (optional)
 	 * @return Boolean: whether $table has filed $field
 	 */
-	function fieldExists( $table, $field, $fname = 'DatabaseBase::fieldExists' ) {
+	public function fieldExists( $table, $field, $fname = 'DatabaseBase::fieldExists' ) {
 		$info = $this->fieldInfo( $table, $field );
 
 		return (bool)$info;
@@ -1544,7 +1529,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool|null
 	 */
-	function indexExists( $table, $index, $fname = 'DatabaseBase::indexExists' ) {
+	public function indexExists( $table, $index, $fname = 'DatabaseBase::indexExists' ) {
 		$info = $this->indexInfo( $table, $index, $fname );
 		if ( is_null( $info ) ) {
 			return null;
@@ -1561,7 +1546,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function tableExists( $table, $fname = __METHOD__ ) {
+	public function tableExists( $table, $fname = __METHOD__ ) {
 		$table = $this->tableName( $table );
 		$old = $this->ignoreErrors( true );
 		$res = $this->query( "SELECT 1 FROM $table LIMIT 1", $fname );
@@ -1576,7 +1561,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $index
 	 * @return string
 	 */
-	function fieldType( $res, $index ) {
+	public function fieldType( $res, $index ) {
 		if ( $res instanceof ResultWrapper ) {
 			$res = $res->result;
 		}
@@ -1592,7 +1577,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function indexUnique( $table, $index ) {
+	public function indexUnique( $table, $index ) {
 		$indexInfo = $this->indexInfo( $table, $index );
 
 		if ( !$indexInfo ) {
@@ -1608,7 +1593,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $options array
 	 * @return string
 	 */
-	function makeInsertOptions( $options ) {
+	protected function makeInsertOptions( $options ) {
 		return implode( ' ', $options );
 	}
 
@@ -1645,7 +1630,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function insert( $table, $a, $fname = 'DatabaseBase::insert', $options = array() ) {
+	public function insert( $table, $a, $fname = 'DatabaseBase::insert', $options = array() ) {
 		# No rows to insert, easy just return now
 		if ( !count( $a ) ) {
 			return true;
@@ -1693,7 +1678,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $options Array: The options passed to DatabaseBase::update
 	 * @return string
 	 */
-	function makeUpdateOptions( $options ) {
+	protected function makeUpdateOptions( $options ) {
 		if ( !is_array( $options ) ) {
 			$options = array( $options );
 		}
@@ -1759,7 +1744,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return string
 	 */
-	function makeList( $a, $mode = LIST_COMMA ) {
+	public function makeList( $a, $mode = LIST_COMMA ) {
 		if ( !is_array( $a ) ) {
 			throw new DBUnexpectedError( $this, 'DatabaseBase::makeList called with incorrect parameters' );
 		}
@@ -1819,12 +1804,12 @@ abstract class DatabaseBase implements DatabaseType {
 	 * The keys on each level may be either integers or strings.
 	 *
 	 * @param $data Array: organized as 2-d
-	 *              array(baseKeyVal => array(subKeyVal => <ignored>, ...), ...)
+	 *              array(baseKeyVal => array(subKeyVal => [ignored], ...), ...)
 	 * @param $baseKey String: field name to match the base-level keys to (eg 'pl_namespace')
 	 * @param $subKey String: field name to match the sub-level keys to (eg 'pl_title')
 	 * @return Mixed: string SQL fragment, or false if no items in array.
 	 */
-	function makeWhereFrom2d( $data, $baseKey, $subKey ) {
+	public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
 		$conds = array();
 
 		foreach ( $data as $base => $sub ) {
@@ -1844,14 +1829,22 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Bitwise operations
+	 * Return aggregated value alias
+	 *
+	 * @param $valuedata
+	 * @param $valuename string
+	 *
+	 * @return string
 	 */
+	public function aggregateValue( $valuedata, $valuename = 'value' ) {
+		return $valuename;
+	}
 
 	/**
 	 * @param $field
 	 * @return string
 	 */
-	function bitNot( $field ) {
+	public function bitNot( $field ) {
 		return "(~$field)";
 	}
 
@@ -1860,7 +1853,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $fieldRight
 	 * @return string
 	 */
-	function bitAnd( $fieldLeft, $fieldRight ) {
+	public function bitAnd( $fieldLeft, $fieldRight ) {
 		return "($fieldLeft & $fieldRight)";
 	}
 
@@ -1869,11 +1862,20 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param  $fieldRight
 	 * @return string
 	 */
-	function bitOr( $fieldLeft, $fieldRight ) {
+	public function bitOr( $fieldLeft, $fieldRight ) {
 		return "($fieldLeft | $fieldRight)";
 	}
 
 	/**
+	 * Build a concatenation list to feed into a SQL query
+	 * @param $stringList Array: list of raw SQL expressions; caller is responsible for any quoting
+	 * @return String
+	 */
+	public function buildConcat( $stringList ) {
+		return 'CONCAT(' . implode( ',', $stringList ) . ')';
+	}
+
+	/**
 	 * Change the current database
 	 *
 	 * @todo Explain what exactly will fail if this is not overridden.
@@ -1882,7 +1884,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool Success or failure
 	 */
-	function selectDB( $db ) {
+	public function selectDB( $db ) {
 		# Stub.  Shouldn't cause serious problems if it's not overridden, but
 		# if your database engine supports a concept similar to MySQL's
 		# databases you may as well.
@@ -1893,14 +1895,14 @@ abstract class DatabaseBase implements DatabaseType {
 	/**
 	 * Get the current DB name
 	 */
-	function getDBname() {
+	public function getDBname() {
 		return $this->mDBname;
 	}
 
 	/**
 	 * Get the server hostname or IP address
 	 */
-	function getServer() {
+	public function getServer() {
 		return $this->mServer;
 	}
 
@@ -1921,7 +1923,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *   raw - Do not add identifier quotes to the table name
 	 * @return String: full database name
 	 */
-	function tableName( $name, $format = 'quoted' ) {
+	public function tableName( $name, $format = 'quoted' ) {
 		global $wgSharedDB, $wgSharedPrefix, $wgSharedTables;
 		# Skip the entire process when we have a string quoted on both ends.
 		# Note that we check the end so that we will still quote any use of
@@ -2067,6 +2069,39 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
+	 * Get an aliased field name
+	 * e.g. fieldName AS newFieldName
+	 *
+	 * @param $name string Field name
+	 * @param $alias string|bool Alias (optional)
+	 * @return string SQL name for aliased field. Will not alias a field to its own name
+	 */
+	public function fieldNameWithAlias( $name, $alias = false ) {
+		if ( !$alias || (string)$alias === (string)$name ) {
+			return $name;
+		} else {
+			return $name . ' AS ' . $alias; //PostgreSQL needs AS
+		}
+	}
+
+	/**
+	 * Gets an array of aliased field names
+	 *
+	 * @param $fields array( [alias] => field )
+	 * @return array of strings, see fieldNameWithAlias()
+	 */
+	public function fieldNamesWithAlias( $fields ) {
+		$retval = array();
+		foreach ( $fields as $alias => $field ) {
+			if ( is_numeric( $alias ) ) {
+				$alias = $field;
+			}
+			$retval[] = $this->fieldNameWithAlias( $field, $alias );
+		}
+		return $retval;
+	}
+
+	/**
 	 * Get the aliased table name clause for a FROM clause
 	 * which might have a JOIN and/or USE INDEX clause
 	 *
@@ -2134,7 +2169,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return string
 	 */
-	function indexName( $index ) {
+	protected function indexName( $index ) {
 		// Backwards-compatibility hack
 		$renamed = array(
 			'ar_usertext_timestamp'	=> 'usertext_timestamp',
@@ -2157,7 +2192,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return string
 	 */
-	function addQuotes( $s ) {
+	public function addQuotes( $s ) {
 		if ( $s === null ) {
 			return 'NULL';
 		} else {
@@ -2196,36 +2231,6 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Backwards compatibility, identifier quoting originated in DatabasePostgres
-	 * which used quote_ident which does not follow our naming conventions
-	 * was renamed to addIdentifierQuotes.
-	 * @deprecated since 1.18 use addIdentifierQuotes
-	 *
-	 * @param $s string
-	 *
-	 * @return string
-	 */
-	function quote_ident( $s ) {
-		wfDeprecated( __METHOD__, '1.18' );
-		return $this->addIdentifierQuotes( $s );
-	}
-
-	/**
-	 * Escape string for safe LIKE usage.
-	 * WARNING: you should almost never use this function directly,
-	 * instead use buildLike() that escapes everything automatically
-	 * @deprecated since 1.17, warnings in 1.17, removed in ???
-	 *
-	 * @param $s string
-	 *
-	 * @return string
-	 */
-	public function escapeLike( $s ) {
-		wfDeprecated( __METHOD__, '1.17' );
-		return $this->escapeLikeInternal( $s );
-	}
-
-	/**
 	 * @param $s string
 	 * @return string
 	 */
@@ -2249,7 +2254,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @since 1.16
 	 * @return String: fully built LIKE statement
 	 */
-	function buildLike() {
+	public function buildLike() {
 		$params = func_get_args();
 
 		if ( count( $params ) > 0 && is_array( $params[0] ) ) {
@@ -2274,7 +2279,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return LikeMatch
 	 */
-	function anyChar() {
+	public function anyChar() {
 		return new LikeMatch( '_' );
 	}
 
@@ -2283,7 +2288,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return LikeMatch
 	 */
-	function anyString() {
+	public function anyString() {
 		return new LikeMatch( '%' );
 	}
 
@@ -2298,7 +2303,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $seqName string
 	 * @return null
 	 */
-	function nextSequenceValue( $seqName ) {
+	public function nextSequenceValue( $seqName ) {
 		return null;
 	}
 
@@ -2312,7 +2317,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $index
 	 * @return string
 	 */
-	function useIndexClause( $index ) {
+	public function useIndexClause( $index ) {
 		return '';
 	}
 
@@ -2338,7 +2343,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *    a field name or an array of field names
 	 * @param $fname String: Calling function name (use __METHOD__) for logs/profiling
 	 */
-	function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseBase::replace' ) {
+	public function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseBase::replace' ) {
 		$quotedTable = $this->tableName( $table );
 
 		if ( count( $rows ) == 0 ) {
@@ -2439,7 +2444,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $fname      String: Calling function name (use __METHOD__) for
 	 *                    logs/profiling
 	 */
-	function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
+	public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
 		$fname = 'DatabaseBase::deleteJoin' )
 	{
 		if ( !$conds ) {
@@ -2466,7 +2471,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return int
 	 */
-	function textFieldSize( $table, $field ) {
+	public function textFieldSize( $table, $field ) {
 		$table = $this->tableName( $table );
 		$sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
 		$res = $this->query( $sql, 'DatabaseBase::textFieldSize' );
@@ -2491,7 +2496,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @return string Returns the text of the low priority option if it is
 	 *   supported, or a blank string otherwise
 	 */
-	function lowPriorityOption() {
+	public function lowPriorityOption() {
 		return '';
 	}
 
@@ -2505,7 +2510,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function delete( $table, $conds, $fname = 'DatabaseBase::delete' ) {
+	public function delete( $table, $conds, $fname = 'DatabaseBase::delete' ) {
 		if ( !$conds ) {
 			throw new DBUnexpectedError( $this, 'DatabaseBase::delete() called with no conditions' );
 		}
@@ -2546,7 +2551,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return ResultWrapper
 	 */
-	function insertSelect( $destTable, $srcTable, $varMap, $conds,
+	public function insertSelect( $destTable, $srcTable, $varMap, $conds,
 		$fname = 'DatabaseBase::insertSelect',
 		$insertOptions = array(), $selectOptions = array() )
 	{
@@ -2592,35 +2597,24 @@ abstract class DatabaseBase implements DatabaseType {
 	 * If the result of the query is not ordered, then the rows to be returned
 	 * are theoretically arbitrary.
 	 *
-	 * $sql is expected to be a SELECT, if that makes a difference.  For
-	 * UPDATE, limitResultForUpdate should be used.
+	 * $sql is expected to be a SELECT, if that makes a difference.
 	 *
 	 * The version provided by default works in MySQL and SQLite.  It will very
 	 * likely need to be overridden for most other DBMSes.
 	 *
 	 * @param $sql String SQL query we will append the limit too
 	 * @param $limit Integer the SQL limit
-	 * @param $offset Integer|false the SQL offset (default false)
+	 * @param $offset Integer|bool the SQL offset (default false)
 	 *
 	 * @return string
 	 */
-	function limitResult( $sql, $limit, $offset = false ) {
+	public function limitResult( $sql, $limit, $offset = false ) {
 		if ( !is_numeric( $limit ) ) {
 			throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" );
 		}
-
 		return "$sql LIMIT "
-				. ( ( is_numeric( $offset ) && $offset != 0 ) ? "{$offset}," : "" )
-				. "{$limit} ";
-	}
-
-	/**
-	 * @param $sql
-	 * @param $num
-	 * @return string
-	 */
-	function limitResultForUpdate( $sql, $num ) {
-		return $this->limitResult( $sql, $num, 0 );
+			. ( ( is_numeric( $offset ) && $offset != 0 ) ? "{$offset}," : "" )
+			. "{$limit} ";
 	}
 
 	/**
@@ -2628,7 +2622,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * within the UNION construct.
 	 * @return Boolean
 	 */
-	function unionSupportsOrderAndLimit() {
+	public function unionSupportsOrderAndLimit() {
 		return true; // True for almost every DB supported
 	}
 
@@ -2640,7 +2634,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $all Boolean: use UNION ALL
 	 * @return String: SQL fragment
 	 */
-	function unionQueries( $sqls, $all ) {
+	public function unionQueries( $sqls, $all ) {
 		$glue = $all ? ') UNION ALL (' : ') UNION (';
 		return '(' . implode( $glue, $sqls ) . ')';
 	}
@@ -2649,12 +2643,15 @@ abstract class DatabaseBase implements DatabaseType {
 	 * Returns an SQL expression for a simple conditional.  This doesn't need
 	 * to be overridden unless CASE isn't supported in your DBMS.
 	 *
-	 * @param $cond String: SQL expression which will result in a boolean value
+	 * @param $cond string|array SQL expression which will result in a boolean value
 	 * @param $trueVal String: SQL expression to return if true
 	 * @param $falseVal String: SQL expression to return if false
 	 * @return String: SQL fragment
 	 */
-	function conditional( $cond, $trueVal, $falseVal ) {
+	public function conditional( $cond, $trueVal, $falseVal ) {
+		if ( is_array( $cond ) ) {
+			$cond = $this->makeList( $cond, LIST_AND );
+		}
 		return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
 	}
 
@@ -2668,7 +2665,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return string
 	 */
-	function strreplace( $orig, $old, $new ) {
+	public function strreplace( $orig, $old, $new ) {
 		return "REPLACE({$orig}, {$old}, {$new})";
 	}
 
@@ -2678,7 +2675,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return int
 	 */
-	function getServerUptime() {
+	public function getServerUptime() {
 		return 0;
 	}
 
@@ -2688,7 +2685,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function wasDeadlock() {
+	public function wasDeadlock() {
 		return false;
 	}
 
@@ -2698,7 +2695,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function wasLockTimeout() {
+	public function wasLockTimeout() {
 		return false;
 	}
 
@@ -2709,7 +2706,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function wasErrorReissuable() {
+	public function wasErrorReissuable() {
 		return false;
 	}
 
@@ -2719,7 +2716,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function wasReadOnlyError() {
+	public function wasReadOnlyError() {
 		return false;
 	}
 
@@ -2741,8 +2738,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool
 	 */
-	function deadlockLoop() {
-
+	public function deadlockLoop() {
 		$this->begin( __METHOD__ );
 		$args = func_get_args();
 		$function = array_shift( $args );
@@ -2790,11 +2786,11 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $timeout Integer: the maximum number of seconds to wait for
 	 *   synchronisation
 	 *
-	 * @return An integer: zero if the slave was past that position already,
+	 * @return integer: zero if the slave was past that position already,
 	 *   greater than zero if we waited for some period of time, less than
 	 *   zero if we timed out.
 	 */
-	function masterPosWait( DBMasterPos $pos, $timeout ) {
+	public function masterPosWait( DBMasterPos $pos, $timeout ) {
 		wfProfileIn( __METHOD__ );
 
 		if ( !is_null( $this->mFakeSlaveLag ) ) {
@@ -2827,7 +2823,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return DBMasterPos, or false if this is not a slave.
 	 */
-	function getSlavePos() {
+	public function getSlavePos() {
 		if ( !is_null( $this->mFakeSlaveLag ) ) {
 			$pos = new MySQLMasterPos( 'fake', microtime( true ) - $this->mFakeSlaveLag );
 			wfDebug( __METHOD__ . ": fake slave pos = $pos\n" );
@@ -2843,7 +2839,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return DBMasterPos, or false if this is not a master
 	 */
-	function getMasterPos() {
+	public function getMasterPos() {
 		if ( $this->mFakeMaster ) {
 			return new MySQLMasterPos( 'fake', microtime( true ) );
 		} else {
@@ -2852,11 +2848,65 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Begin a transaction, committing any previously open transaction
+	 * Run an anonymous function as soon as there is no transaction pending.
+	 * If there is a transaction and it is rolled back, then the callback is cancelled.
+	 * Callbacks must commit any transactions that they begin.
+	 *
+	 * This is useful for updates to different systems or separate transactions are needed.
+	 *
+	 * @param Closure $callback
+	 * @return void
+	 */
+	final public function onTransactionIdle( Closure $callback ) {
+		if ( $this->mTrxLevel ) {
+			$this->mTrxIdleCallbacks[] = $callback;
+		} else {
+			$callback();
+		}
+	}
+
+	/**
+	 * Actually run the "on transaction idle" callbacks
+	 */
+	protected function runOnTransactionIdleCallbacks() {
+		$autoTrx = $this->getFlag( DBO_TRX ); // automatic begin() enabled?
+
+		$e = null; // last exception
+		do { // callbacks may add callbacks :)
+			$callbacks = $this->mTrxIdleCallbacks;
+			$this->mTrxIdleCallbacks = array(); // recursion guard
+			foreach ( $callbacks as $callback ) {
+				try {
+					$this->clearFlag( DBO_TRX ); // make each query its own transaction
+					$callback();
+					$this->setFlag( $autoTrx ? DBO_TRX : 0 ); // restore automatic begin()
+				} catch ( Exception $e ) {}
+			}
+		} while ( count( $this->mTrxIdleCallbacks ) );
+
+		if ( $e instanceof Exception ) {
+			throw $e; // re-throw any last exception
+		}
+	}
+
+	/**
+	 * Begin a transaction
 	 *
 	 * @param $fname string
 	 */
-	function begin( $fname = 'DatabaseBase::begin' ) {
+	final public function begin( $fname = 'DatabaseBase::begin' ) {
+		if ( $this->mTrxLevel ) { // implicit commit
+			$this->doCommit( $fname );
+			$this->runOnTransactionIdleCallbacks();
+		}
+		$this->doBegin( $fname );
+	}
+
+	/**
+	 * @see DatabaseBase::begin()
+	 * @param type $fname
+	 */
+	protected function doBegin( $fname ) {
 		$this->query( 'BEGIN', $fname );
 		$this->mTrxLevel = 1;
 	}
@@ -2866,7 +2916,16 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @param $fname string
 	 */
-	function commit( $fname = 'DatabaseBase::commit' ) {
+	final public function commit( $fname = 'DatabaseBase::commit' ) {
+		$this->doCommit( $fname );
+		$this->runOnTransactionIdleCallbacks();
+	}
+
+	/**
+	 * @see DatabaseBase::commit()
+	 * @param type $fname
+	 */
+	protected function doCommit( $fname ) {
 		if ( $this->mTrxLevel ) {
 			$this->query( 'COMMIT', $fname );
 			$this->mTrxLevel = 0;
@@ -2879,7 +2938,16 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @param $fname string
 	 */
-	function rollback( $fname = 'DatabaseBase::rollback' ) {
+	final public function rollback( $fname = 'DatabaseBase::rollback' ) {
+		$this->doRollback( $fname );
+		$this->mTrxIdleCallbacks = array(); // cancel
+	}
+
+	/**
+	 * @see DatabaseBase::rollback()
+	 * @param type $fname
+	 */
+	protected function doRollback( $fname ) {
 		if ( $this->mTrxLevel ) {
 			$this->query( 'ROLLBACK', $fname, true );
 			$this->mTrxLevel = 0;
@@ -2900,7 +2968,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $fname String: calling function name
 	 * @return Boolean: true if operation was successful
 	 */
-	function duplicateTableStructure( $oldName, $newName, $temporary = false,
+	public function duplicateTableStructure( $oldName, $newName, $temporary = false,
 		$fname = 'DatabaseBase::duplicateTableStructure' )
 	{
 		throw new MWException(
@@ -2910,7 +2978,7 @@ abstract class DatabaseBase implements DatabaseType {
 	/**
 	 * List all tables on the database
 	 *
-	 * @param $prefix Only show tables with this prefix, e.g. mw_
+	 * @param $prefix string Only show tables with this prefix, e.g. mw_
 	 * @param $fname String: calling function name
 	 */
 	function listTables( $prefix = null, $fname = 'DatabaseBase::listTables' ) {
@@ -2928,7 +2996,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return string
 	 */
-	function timestamp( $ts = 0 ) {
+	public function timestamp( $ts = 0 ) {
 		return wfTimestamp( TS_MW, $ts );
 	}
 
@@ -2945,7 +3013,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return string
 	 */
-	function timestampOrNull( $ts = null ) {
+	public function timestampOrNull( $ts = null ) {
 		if ( is_null( $ts ) ) {
 			return null;
 		} else {
@@ -2968,7 +3036,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 *
 	 * @return bool|ResultWrapper
 	 */
-	function resultObject( $result ) {
+	public function resultObject( $result ) {
 		if ( empty( $result ) ) {
 			return false;
 		} elseif ( $result instanceof ResultWrapper ) {
@@ -2982,23 +3050,11 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Return aggregated value alias
-	 *
-	 * @param $valuedata
-	 * @param $valuename string
-	 *
-	 * @return string
-	 */
-	function aggregateValue ( $valuedata, $valuename = 'value' ) {
-		return $valuename;
-	}
-
-	/**
 	 * Ping the server and try to reconnect if it there is no connection
 	 *
 	 * @return bool Success or failure
 	 */
-	function ping() {
+	public function ping() {
 		# Stub.  Not essential to override.
 		return true;
 	}
@@ -3010,9 +3066,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 * installations. Most callers should use LoadBalancer::safeGetLag()
 	 * instead.
 	 *
-	 * @return Database replication lag in seconds
+	 * @return int Database replication lag in seconds
 	 */
-	function getLag() {
+	public function getLag() {
 		return intval( $this->mFakeSlaveLag );
 	}
 
@@ -3033,7 +3089,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $b string
 	 * @return string
 	 */
-	function encodeBlob( $b ) {
+	public function encodeBlob( $b ) {
 		return $b;
 	}
 
@@ -3044,23 +3100,11 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $b string
 	 * @return string
 	 */
-	function decodeBlob( $b ) {
+	public function decodeBlob( $b ) {
 		return $b;
 	}
 
 	/**
-	 * Override database's default connection timeout
-	 *
-	 * @param $timeout Integer in seconds
-	 * @return void
-	 * @deprecated since 1.19; use setSessionOptions()
-	 */
-	public function setTimeout( $timeout ) {
-		wfDeprecated( __METHOD__, '1.19' );
-		$this->setSessionOptions( array( 'connTimeout' => $timeout ) );
-	}
-
-	/**
 	 * Override database's default behavior. $options include:
 	 *     'connTimeout' : Set the connection timeout value in seconds.
 	 *                     May be useful for very long batch queries such as
@@ -3085,7 +3129,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 *      generated dynamically using $filename
 	 * @return bool|string
 	 */
-	function sourceFile( $filename, $lineCallback = false, $resultCallback = false, $fname = false ) {
+	public function sourceFile(
+		$filename, $lineCallback = false, $resultCallback = false, $fname = false
+	) {
 		wfSuppressWarnings();
 		$fp = fopen( $filename, 'r' );
 		wfRestoreWarnings();
@@ -3135,9 +3181,9 @@ abstract class DatabaseBase implements DatabaseType {
 	 * ones in $GLOBALS. If an array is set here, $GLOBALS will not be used at
 	 * all. If it's set to false, $GLOBALS will be used.
 	 *
-	 * @param $vars False, or array mapping variable name to value.
+	 * @param $vars bool|array mapping variable name to value.
 	 */
-	function setSchemaVars( $vars ) {
+	public function setSchemaVars( $vars ) {
 		$this->mSchemaVars = $vars;
 	}
 
@@ -3323,12 +3369,15 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Build a concatenation list to feed into a SQL query
-	 * @param $stringList Array: list of raw SQL expressions; caller is responsible for any quoting
-	 * @return String
+	 * Check to see if a named lock is available. This is non-blocking.
+	 *
+	 * @param $lockName String: name of lock to poll
+	 * @param $method String: name of method calling us
+	 * @return Boolean
+	 * @since 1.20
 	 */
-	function buildConcat( $stringList ) {
-		return 'CONCAT(' . implode( ',', $stringList ) . ')';
+	public function lockIsFree( $lockName, $method ) {
+		return true;
 	}
 
 	/**
@@ -3352,7 +3401,7 @@ abstract class DatabaseBase implements DatabaseType {
 	 * @param $lockName String: Name of lock to release
 	 * @param $method String: Name of method calling us
 	 *
-	 * @return Returns 1 if the lock was released, 0 if the lock was not established
+	 * @return int Returns 1 if the lock was released, 0 if the lock was not established
 	 * by this thread (in which case the lock is not released), and NULL if the named
 	 * lock did not exist
 	 */
@@ -3425,17 +3474,28 @@ abstract class DatabaseBase implements DatabaseType {
 	}
 
 	/**
-	 * Encode an expiry time
+	 * Encode an expiry time into the DBMS dependent format
 	 *
 	 * @param $expiry String: timestamp for expiry, or the 'infinity' string
 	 * @return String
 	 */
 	public function encodeExpiry( $expiry ) {
-		if ( $expiry == '' || $expiry == $this->getInfinity() ) {
-			return $this->getInfinity();
-		} else {
-			return $this->timestamp( $expiry );
-		}
+		return ( $expiry == '' || $expiry == 'infinity' || $expiry == $this->getInfinity() )
+			? $this->getInfinity()
+			: $this->timestamp( $expiry );
+	}
+
+	/**
+	 * Decode an expiry time into a DBMS independent format
+	 *
+	 * @param $expiry String: DB timestamp field value for expiry
+	 * @param $format integer: TS_* constant, defaults to TS_MW
+	 * @return String
+	 */
+	public function decodeExpiry( $expiry, $format = TS_MW ) {
+		return ( $expiry == '' || $expiry == $this->getInfinity() )
+			? 'infinity'
+			: wfTimestamp( $format, $expiry );
 	}
 
 	/**
@@ -3450,4 +3510,17 @@ abstract class DatabaseBase implements DatabaseType {
 	public function setBigSelects( $value = true ) {
 		// no-op
 	}
+
+	/**
+	 * @since 1.19
+	 */
+	public function __toString() {
+		return (string)$this->mConn;
+	}
+
+	public function __destruct() {
+		if ( count( $this->mTrxIdleCallbacks ) ) { // sanity
+			trigger_error( "Transaction idle callbacks still pending." );
+		}
+	}
 }