From: Aaron Schulz <aschulz@wikimedia.org>
Date: Wed, 1 Jul 2015 20:23:54 +0000 (-0700)
Subject: Formally defined IDatabase and made a few Database methods protected
X-Git-Tag: 1.31.0-rc.0~10828^2
X-Git-Url: https://git.cyclocoop.org/%7B%24admin_url%7Dmembres/fiche.php?a=commitdiff_plain;h=6e283d394f31ce24470006f09271db2f21a7f0e7;p=lhc%2Fweb%2Fwiklou.git

Formally defined IDatabase and made a few Database methods protected

* IDEs can now make sense of IDatabase, which is useful for
  lazy connections. The interface might also help lower coupling.
* This also updates DBConnRef, which implements IDatabase
* Some discouraged methods are left out of IDatabase.
  These methods either encourage manual query building,
  are only needed by the updater, are obscure/unused,
  or either wise encourage bad practice. DBConnRef still
  supports these if called to avoid breakage though.

Change-Id: Ia83530820f185415725c1d5f54b5172121b4938f
---

diff --git a/autoload.php b/autoload.php
index 8e4da1e4c3..6444e3efa8 100644
--- a/autoload.php
+++ b/autoload.php
@@ -488,10 +488,10 @@ $wgAutoloadLocalClasses = array(
 	'HTMLFileCache' => __DIR__ . '/includes/cache/HTMLFileCache.php',
 	'HTMLFloatField' => __DIR__ . '/includes/htmlform/HTMLFloatField.php',
 	'HTMLForm' => __DIR__ . '/includes/htmlform/HTMLForm.php',
-	'HTMLFormFieldWithButton' => __DIR__ . '/includes/htmlform/HTMLFormFieldWithButton.php',
 	'HTMLFormField' => __DIR__ . '/includes/htmlform/HTMLFormField.php',
 	'HTMLFormFieldCloner' => __DIR__ . '/includes/htmlform/HTMLFormFieldCloner.php',
 	'HTMLFormFieldRequiredOptionsException' => __DIR__ . '/includes/htmlform/HTMLFormFieldRequiredOptionsException.php',
+	'HTMLFormFieldWithButton' => __DIR__ . '/includes/htmlform/HTMLFormFieldWithButton.php',
 	'HTMLHiddenField' => __DIR__ . '/includes/htmlform/HTMLHiddenField.php',
 	'HTMLInfoField' => __DIR__ . '/includes/htmlform/HTMLInfoField.php',
 	'HTMLIntField' => __DIR__ . '/includes/htmlform/HTMLIntField.php',
@@ -530,7 +530,7 @@ $wgAutoloadLocalClasses = array(
 	'ICacheHelper' => __DIR__ . '/includes/cache/CacheHelper.php',
 	'IContextSource' => __DIR__ . '/includes/context/IContextSource.php',
 	'IDBAccessObject' => __DIR__ . '/includes/dao/IDBAccessObject.php',
-	'IDatabase' => __DIR__ . '/includes/db/Database.php',
+	'IDatabase' => __DIR__ . '/includes/db/IDatabase.php',
 	'IEContentAnalyzer' => __DIR__ . '/includes/libs/IEContentAnalyzer.php',
 	'IEUrlExtension' => __DIR__ . '/includes/libs/IEUrlExtension.php',
 	'IJobSpecification' => __DIR__ . '/includes/jobqueue/JobSpecification.php',
@@ -896,6 +896,7 @@ $wgAutoloadLocalClasses = array(
 	'PoolWorkArticleView' => __DIR__ . '/includes/poolcounter/PoolWorkArticleView.php',
 	'PopulateBacklinkNamespace' => __DIR__ . '/maintenance/populateBacklinkNamespace.php',
 	'PopulateCategory' => __DIR__ . '/maintenance/populateCategory.php',
+	'PopulateContentModel' => __DIR__ . '/maintenance/populateContentModel.php',
 	'PopulateFilearchiveSha1' => __DIR__ . '/maintenance/populateFilearchiveSha1.php',
 	'PopulateImageSha1' => __DIR__ . '/maintenance/populateImageSha1.php',
 	'PopulateLogSearch' => __DIR__ . '/maintenance/populateLogSearch.php',
diff --git a/includes/db/DBConnRef.php b/includes/db/DBConnRef.php
index 7045494abd..b4f3f79229 100644
--- a/includes/db/DBConnRef.php
+++ b/includes/db/DBConnRef.php
@@ -3,6 +3,7 @@
  * Helper class to handle automatically marking connections as reusable (via RAII pattern)
  * as well handling deferring the actual network connection until the handle is used
  *
+ * @note: proxy methods are defined explicity to avoid interface errors
  * @ingroup Database
  * @since 1.22
  */
@@ -29,7 +30,7 @@ class DBConnRef implements IDatabase {
 		}
 	}
 
-	public function __call( $name, $arguments ) {
+	function __call( $name, array $arguments ) {
 		if ( $this->conn === null ) {
 			list( $db, $groups, $wiki ) = $this->params;
 			$this->conn = $this->lb->getConnection( $db, $groups, $wiki );
@@ -38,7 +39,484 @@ class DBConnRef implements IDatabase {
 		return call_user_func_array( array( $this->conn, $name ), $arguments );
 	}
 
-	public function __destruct() {
+	public function getServerInfo() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function bufferResults( $buffer = null ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function trxLevel() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function trxTimestamp() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function tablePrefix( $prefix = null ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function dbSchema( $schema = null ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getLBInfo( $name = null ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function setLBInfo( $name, $value = null ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function implicitGroupby() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function implicitOrderby() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function lastQuery() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function doneWrites() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function lastDoneWrites() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function writesOrCallbacksPending() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function pendingWriteQueryDuration() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function isOpen() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function setFlag( $flag ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function clearFlag( $flag ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getFlag( $flag ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getProperty( $name ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getWikiID() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getType() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function open( $server, $user, $password, $dbName ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function fetchObject( $res ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function fetchRow( $res ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function numRows( $res ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function numFields( $res ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function fieldName( $res, $n ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function insertId() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function dataSeek( $res, $row ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function lastErrno() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function lastError() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function fieldInfo( $table, $field ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function affectedRows() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getSoftwareLink() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getServerVersion() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function close() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function reportConnectionError( $error = 'Unknown error' ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function query( $sql, $fname = __METHOD__, $tempIgnore = false ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function freeResult( $res ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function selectField(
+		$table, $var, $cond = '', $fname = __METHOD__, $options = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function selectFieldValues(
+		$table, $var, $cond = '', $fname = __METHOD__, $options = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function select(
+		$table, $vars, $conds = '', $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function selectSQLText(
+		$table, $vars, $conds = '', $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function selectRow(
+		$table, $vars, $conds, $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function estimateRowCount(
+		$table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function selectRowCount(
+		$table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function fieldExists( $table, $field, $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function indexExists( $table, $index, $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function tableExists( $table, $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function indexUnique( $table, $index ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function insert( $table, $a, $fname = __METHOD__, $options = array() ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function update( $table, $values, $conds, $fname = __METHOD__, $options = array() ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function makeList( $a, $mode = LIST_COMMA ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function bitNot( $field ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function bitAnd( $fieldLeft, $fieldRight ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function bitOr( $fieldLeft, $fieldRight ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function buildConcat( $stringList ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function buildGroupConcatField(
+		$delim, $table, $field, $conds = '', $join_conds = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function selectDB( $db ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getDBname() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getServer() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function addQuotes( $s ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function buildLike() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function anyChar() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function anyString() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function nextSequenceValue( $seqName ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function upsert(
+		$table, array $rows, array $uniqueIndexes, array $set, $fname = __METHOD__
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function deleteJoin(
+		$delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function delete( $table, $conds, $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function insertSelect(
+		$destTable, $srcTable, $varMap, $conds,
+		$fname = __METHOD__, $insertOptions = array(), $selectOptions = array()
+	) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function unionSupportsOrderAndLimit() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function unionQueries( $sqls, $all ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function conditional( $cond, $trueVal, $falseVal ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function strreplace( $orig, $old, $new ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getServerUptime() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function wasDeadlock() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function wasLockTimeout() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function wasErrorReissuable() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function wasReadOnlyError() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function masterPosWait( DBMasterPos $pos, $timeout ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getSlavePos() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getMasterPos() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function onTransactionIdle( $callback ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function onTransactionPreCommitOrIdle( $callback ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function startAtomic( $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function endAtomic( $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function begin( $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function commit( $fname = __METHOD__, $flush = '' ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function rollback( $fname = __METHOD__, $flush = '' ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function listTables( $prefix = null, $fname = __METHOD__ ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function timestamp( $ts = 0 ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function timestampOrNull( $ts = null ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function resultObject( $result ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function ping() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getLag() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function maxListLen() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function encodeBlob( $b ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function decodeBlob( $b ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function setSessionOptions( array $options ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function setSchemaVars( $vars ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function lockIsFree( $lockName, $method ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function lock( $lockName, $method, $timeout = 5 ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function unlock( $lockName, $method ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function namedLocksEnqueue() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function getInfinity() {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function encodeExpiry( $expiry ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function decodeExpiry( $expiry, $format = TS_MW ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	public function setBigSelects( $value = true ) {
+		return $this->__call( __FUNCTION__, func_get_args() );
+	}
+
+	/**
+	 * Clean up the connection when out of scope
+	 */
+	function __destruct() {
 		if ( $this->conn !== null ) {
 			$this->lb->reuseConnection( $this->conn );
 		}
diff --git a/includes/db/Database.php b/includes/db/Database.php
index e74fe80690..84c4a665ac 100644
--- a/includes/db/Database.php
+++ b/includes/db/Database.php
@@ -25,13 +25,6 @@
  * @ingroup Database
  */
 
-/**
- * Interface for classes that implement or wrap DatabaseBase
- * @ingroup Database
- */
-interface IDatabase {
-}
-
 /**
  * Database abstraction object
  * @ingroup Database
@@ -1067,7 +1060,7 @@ abstract class DatabaseBase implements IDatabase {
 	 * @param string $sql
 	 * @return bool
 	 */
-	public function isWriteQuery( $sql ) {
+	protected function isWriteQuery( $sql ) {
 		return !preg_match( '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SET|SHOW|EXPLAIN|\(SELECT)\b/i', $sql );
 	}
 
@@ -1080,7 +1073,7 @@ abstract class DatabaseBase implements IDatabase {
 	 * @param string $sql
 	 * @return bool
 	 */
-	public function isTransactableQuery( $sql ) {
+	protected function isTransactableQuery( $sql ) {
 		$verb = substr( $sql, 0, strcspn( $sql, " \t\r\n" ) );
 		return !in_array( $verb, array( 'BEGIN', 'COMMIT', 'ROLLBACK', 'SHOW', 'SET' ) );
 	}
@@ -1458,6 +1451,7 @@ abstract class DatabaseBase implements IDatabase {
 	 * @param string|array $options The query options. See DatabaseBase::select() for details.
 	 *
 	 * @return bool|array The values from the field, or false on failure
+	 * @throws DBUnexpectedError
 	 * @since 1.25
 	 */
 	public function selectFieldValues(
diff --git a/includes/db/IDatabase.php b/includes/db/IDatabase.php
new file mode 100644
index 0000000000..49d0514da2
--- /dev/null
+++ b/includes/db/IDatabase.php
@@ -0,0 +1,1513 @@
+<?php
+
+/**
+ * @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
+ */
+
+/**
+ * Basic database interface for live and lazy-loaded DB handles
+ *
+ * @todo: loosen up DB classes from MWException
+ * @note: DatabaseBase and DBConnRef should be updated to reflect any changes
+ * @ingroup Database
+ */
+interface IDatabase {
+	/**
+	 * A string describing the current software version, and possibly
+	 * other details in a user-friendly way. Will be listed on Special:Version, etc.
+	 * Use getServerVersion() to get machine-friendly information.
+	 *
+	 * @return string Version information from the database server
+	 */
+	public function getServerInfo();
+
+	/**
+	 * Turns buffering of SQL result sets on (true) or off (false). Default is
+	 * "on".
+	 *
+	 * Unbuffered queries are very troublesome in MySQL:
+	 *
+	 *   - If another query is executed while the first query is being read
+	 *     out, the first query is killed. This means you can't call normal
+	 *     MediaWiki functions while you are reading an unbuffered query result
+	 *     from a normal wfGetDB() connection.
+	 *
+	 *   - Unbuffered queries cause the MySQL server to use large amounts of
+	 *     memory and to hold broad locks which block other queries.
+	 *
+	 * If you want to limit client-side memory, it's almost always better to
+	 * split up queries into batches using a LIMIT clause than to switch off
+	 * buffering.
+	 *
+	 * @param null|bool $buffer
+	 * @return null|bool The previous value of the flag
+	 */
+	public function bufferResults( $buffer = null );
+
+	/**
+	 * Gets the current transaction level.
+	 *
+	 * Historically, transactions were allowed to be "nested". This is no
+	 * longer supported, so this function really only returns a boolean.
+	 *
+	 * @return int The previous value
+	 */
+	public function trxLevel();
+
+	/**
+	 * Get the UNIX timestamp of the time that the transaction was established
+	 *
+	 * This can be used to reason about the staleness of SELECT data
+	 * in REPEATABLE-READ transaction isolation level.
+	 *
+	 * @return float|null Returns null if there is not active transaction
+	 * @since 1.25
+	 */
+	public function trxTimestamp();
+
+	/**
+	 * Get/set the table prefix.
+	 * @param string $prefix The table prefix to set, or omitted to leave it unchanged.
+	 * @return string The previous table prefix.
+	 */
+	public function tablePrefix( $prefix = null );
+
+	/**
+	 * Get/set the db schema.
+	 * @param string $schema The database schema to set, or omitted to leave it unchanged.
+	 * @return string The previous db schema.
+	 */
+	public function dbSchema( $schema = null );
+
+	/**
+	 * Get properties passed down from the server info array of the load
+	 * balancer.
+	 *
+	 * @param string $name The entry of the info array to get, or null to get the
+	 *   whole array
+	 *
+	 * @return array|mixed|null
+	 */
+	public function getLBInfo( $name = null );
+
+	/**
+	 * Set the LB info array, or a member of it. If called with one parameter,
+	 * the LB info array is set to that parameter. If it is called with two
+	 * parameters, the member with the given name is set to the given value.
+	 *
+	 * @param string $name
+	 * @param array $value
+	 */
+	public function setLBInfo( $name, $value = null );
+
+	/**
+	 * Returns true if this database does an implicit sort when doing GROUP BY
+	 *
+	 * @return bool
+	 */
+	public function implicitGroupby();
+
+	/**
+	 * Returns true if this database does an implicit order by when the column has an index
+	 * For example: SELECT page_title FROM page LIMIT 1
+	 *
+	 * @return bool
+	 */
+	public function implicitOrderby();
+
+	/**
+	 * Return the last query that went through DatabaseBase::query()
+	 * @return string
+	 */
+	public function lastQuery();
+
+	/**
+	 * Returns true if the connection may have been used for write queries.
+	 * Should return true if unsure.
+	 *
+	 * @return bool
+	 */
+	public function doneWrites();
+
+	/**
+	 * Returns the last time the connection may have been used for write queries.
+	 * Should return a timestamp if unsure.
+	 *
+	 * @return int|float UNIX timestamp or false
+	 * @since 1.24
+	 */
+	public function lastDoneWrites();
+
+	/**
+	 * Returns true if there is a transaction open with possible write
+	 * queries or transaction pre-commit/idle callbacks waiting on it to finish.
+	 *
+	 * @return bool
+	 */
+	public function writesOrCallbacksPending();
+
+	/**
+	 * Get the time spend running write queries for this
+	 *
+	 * High times could be due to scanning, updates, locking, and such
+	 *
+	 * @return float|bool Returns false if not transaction is active
+	 * @since 1.26
+	 */
+	public function pendingWriteQueryDuration();
+
+	/**
+	 * Is a connection to the database open?
+	 * @return bool
+	 */
+	public function isOpen();
+
+	/**
+	 * Set a flag for this connection
+	 *
+	 * @param int $flag DBO_* constants from Defines.php:
+	 *   - DBO_DEBUG: output some debug info (same as debug())
+	 *   - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
+	 *   - DBO_TRX: automatically start transactions
+	 *   - DBO_DEFAULT: automatically sets DBO_TRX if not in command line mode
+	 *       and removes it in command line mode
+	 *   - DBO_PERSISTENT: use persistant database connection
+	 */
+	public function setFlag( $flag );
+
+	/**
+	 * Clear a flag for this connection
+	 *
+	 * @param int $flag DBO_* constants from Defines.php:
+	 *   - DBO_DEBUG: output some debug info (same as debug())
+	 *   - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
+	 *   - DBO_TRX: automatically start transactions
+	 *   - DBO_DEFAULT: automatically sets DBO_TRX if not in command line mode
+	 *       and removes it in command line mode
+	 *   - DBO_PERSISTENT: use persistant database connection
+	 */
+	public function clearFlag( $flag );
+
+	/**
+	 * Returns a boolean whether the flag $flag is set for this connection
+	 *
+	 * @param int $flag DBO_* constants from Defines.php:
+	 *   - DBO_DEBUG: output some debug info (same as debug())
+	 *   - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
+	 *   - DBO_TRX: automatically start transactions
+	 *   - DBO_PERSISTENT: use persistant database connection
+	 * @return bool
+	 */
+	public function getFlag( $flag );
+
+	/**
+	 * General read-only accessor
+	 *
+	 * @param string $name
+	 * @return string
+	 */
+	public function getProperty( $name );
+
+	/**
+	 * @return string
+	 */
+	public function getWikiID();
+
+	/**
+	 * Get the type of the DBMS, as it appears in $wgDBtype.
+	 *
+	 * @return string
+	 */
+	public function getType();
+
+	/**
+	 * Open a connection to the database. Usually aborts on failure
+	 *
+	 * @param string $server Database server host
+	 * @param string $user Database user name
+	 * @param string $password Database user password
+	 * @param string $dbName Database name
+	 * @return bool
+	 * @throws DBConnectionError
+	 */
+	public function open( $server, $user, $password, $dbName );
+
+	/**
+	 * Fetch the next row from the given result object, in object form.
+	 * Fields can be retrieved with $row->fieldname, with fields acting like
+	 * member variables.
+	 * If no more rows are available, false is returned.
+	 *
+	 * @param ResultWrapper|stdClass $res Object as returned from DatabaseBase::query(), etc.
+	 * @return stdClass|bool
+	 * @throws DBUnexpectedError Thrown if the database returns an error
+	 */
+	public function fetchObject( $res );
+
+	/**
+	 * Fetch the next row from the given result object, in associative array
+	 * form. Fields are retrieved with $row['fieldname'].
+	 * If no more rows are available, false is returned.
+	 *
+	 * @param ResultWrapper $res Result object as returned from DatabaseBase::query(), etc.
+	 * @return array|bool
+	 * @throws DBUnexpectedError Thrown if the database returns an error
+	 */
+	public function fetchRow( $res );
+
+	/**
+	 * Get the number of rows in a result object
+	 *
+	 * @param mixed $res A SQL result
+	 * @return int
+	 */
+	public function numRows( $res );
+
+	/**
+	 * Get the number of fields in a result object
+	 * @see http://www.php.net/mysql_num_fields
+	 *
+	 * @param mixed $res A SQL result
+	 * @return int
+	 */
+	public function numFields( $res );
+
+	/**
+	 * Get a field name in a result object
+	 * @see http://www.php.net/mysql_field_name
+	 *
+	 * @param mixed $res A SQL result
+	 * @param int $n
+	 * @return string
+	 */
+	public function fieldName( $res, $n );
+
+	/**
+	 * Get the inserted value of an auto-increment row
+	 *
+	 * The value inserted should be fetched from nextSequenceValue()
+	 *
+	 * Example:
+	 * $id = $dbw->nextSequenceValue( 'page_page_id_seq' );
+	 * $dbw->insert( 'page', array( 'page_id' => $id ) );
+	 * $id = $dbw->insertId();
+	 *
+	 * @return int
+	 */
+	public function insertId();
+
+	/**
+	 * Change the position of the cursor in a result object
+	 * @see http://www.php.net/mysql_data_seek
+	 *
+	 * @param mixed $res A SQL result
+	 * @param int $row
+	 */
+	public function dataSeek( $res, $row );
+
+	/**
+	 * Get the last error number
+	 * @see http://www.php.net/mysql_errno
+	 *
+	 * @return int
+	 */
+	public function lastErrno();
+
+	/**
+	 * Get a description of the last error
+	 * @see http://www.php.net/mysql_error
+	 *
+	 * @return string
+	 */
+	public function lastError();
+
+	/**
+	 * mysql_fetch_field() wrapper
+	 * Returns false if the field doesn't exist
+	 *
+	 * @param string $table Table name
+	 * @param string $field Field name
+	 *
+	 * @return Field
+	 */
+	public function fieldInfo( $table, $field );
+
+	/**
+	 * Get the number of rows affected by the last write query
+	 * @see http://www.php.net/mysql_affected_rows
+	 *
+	 * @return int
+	 */
+	public function affectedRows();
+
+	/**
+	 * Returns a wikitext link to the DB's website, e.g.,
+	 *   return "[http://www.mysql.com/ MySQL]";
+	 * Should at least contain plain text, if for some reason
+	 * your database has no website.
+	 *
+	 * @return string Wikitext of a link to the server software's web site
+	 */
+	public function getSoftwareLink();
+
+	/**
+	 * A string describing the current software version, like from
+	 * mysql_get_server_info().
+	 *
+	 * @return string Version information from the database server.
+	 */
+	public function getServerVersion();
+
+	/**
+	 * Closes a database connection.
+	 * if it is open : commits any open transactions
+	 *
+	 * @throws MWException
+	 * @return bool Operation success. true if already closed.
+	 */
+	public function close();
+
+	/**
+	 * @param string $error Fallback error message, used if none is given by DB
+	 * @throws DBConnectionError
+	 */
+	public function reportConnectionError( $error = 'Unknown error' );
+
+	/**
+	 * Run an SQL query and return the result. Normally throws a DBQueryError
+	 * on failure. If errors are ignored, returns false instead.
+	 *
+	 * In new code, the query wrappers select(), insert(), update(), delete(),
+	 * etc. should be used where possible, since they give much better DBMS
+	 * independence and automatically quote or validate user input in a variety
+	 * of contexts. This function is generally only useful for queries which are
+	 * explicitly DBMS-dependent and are unsupported by the query wrappers, such
+	 * as CREATE TABLE.
+	 *
+	 * However, the query wrappers themselves should call this function.
+	 *
+	 * @param string $sql SQL query
+	 * @param string $fname Name of the calling function, for profiling/SHOW PROCESSLIST
+	 *     comment (you can use __METHOD__ or add some extra info)
+	 * @param bool $tempIgnore Whether to avoid throwing an exception on errors...
+	 *     maybe best to catch the exception instead?
+	 * @throws MWException
+	 * @return bool|ResultWrapper True for a successful write query, ResultWrapper object
+	 *     for a successful read query, or false on failure if $tempIgnore set
+	 */
+	public function query( $sql, $fname = __METHOD__, $tempIgnore = false );
+
+	/**
+	 * Report a query error. Log the error, and if neither the object ignore
+	 * flag nor the $tempIgnore flag is set, throw a DBQueryError.
+	 *
+	 * @param string $error
+	 * @param int $errno
+	 * @param string $sql
+	 * @param string $fname
+	 * @param bool $tempIgnore
+	 * @throws DBQueryError
+	 */
+	public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false );
+
+	/**
+	 * Free a result object returned by query() or select(). It's usually not
+	 * necessary to call this, just use unset() or let the variable holding
+	 * the result object go out of scope.
+	 *
+	 * @param mixed $res A SQL result
+	 */
+	public function freeResult( $res );
+
+	/**
+	 * A SELECT wrapper which returns a single field from a single result row.
+	 *
+	 * Usually throws a DBQueryError on failure. If errors are explicitly
+	 * ignored, returns false on failure.
+	 *
+	 * If no result rows are returned from the query, false is returned.
+	 *
+	 * @param string|array $table Table name. See DatabaseBase::select() for details.
+	 * @param string $var The field name to select. This must be a valid SQL
+	 *   fragment: do not use unvalidated user input.
+	 * @param string|array $cond The condition array. See DatabaseBase::select() for details.
+	 * @param string $fname The function name of the caller.
+	 * @param string|array $options The query options. See DatabaseBase::select() for details.
+	 *
+	 * @return bool|mixed The value from the field, or false on failure.
+	 */
+	public function selectField(
+		$table, $var, $cond = '', $fname = __METHOD__, $options = array()
+	);
+
+	/**
+	 * A SELECT wrapper which returns a list of single field values from result rows.
+	 *
+	 * Usually throws a DBQueryError on failure. If errors are explicitly
+	 * ignored, returns false on failure.
+	 *
+	 * If no result rows are returned from the query, false is returned.
+	 *
+	 * @param string|array $table Table name. See DatabaseBase::select() for details.
+	 * @param string $var The field name to select. This must be a valid SQL
+	 *   fragment: do not use unvalidated user input.
+	 * @param string|array $cond The condition array. See DatabaseBase::select() for details.
+	 * @param string $fname The function name of the caller.
+	 * @param string|array $options The query options. See DatabaseBase::select() for details.
+	 *
+	 * @return bool|array The values from the field, or false on failure
+	 * @since 1.25
+	 */
+	public function selectFieldValues(
+		$table, $var, $cond = '', $fname = __METHOD__, $options = array()
+	);
+
+	/**
+	 * Execute a SELECT query constructed using the various parameters provided.
+	 * See below for full details of the parameters.
+	 *
+	 * @param string|array $table Table name
+	 * @param string|array $vars Field names
+	 * @param string|array $conds Conditions
+	 * @param string $fname Caller function name
+	 * @param array $options Query options
+	 * @param array $join_conds Join conditions
+	 *
+	 *
+	 * @param string|array $table
+	 *
+	 * May be either an array of table names, or a single string holding a table
+	 * name. If an array is given, table aliases can be specified, for example:
+	 *
+	 *    array( 'a' => 'user' )
+	 *
+	 * This includes the user table in the query, with the alias "a" available
+	 * for use in field names (e.g. a.user_name).
+	 *
+	 * All of the table names given here are automatically run through
+	 * DatabaseBase::tableName(), which causes the table prefix (if any) to be
+	 * added, and various other table name mappings to be performed.
+	 *
+	 *
+	 * @param string|array $vars
+	 *
+	 * May be either a field name or an array of field names. The field names
+	 * 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)' )
+	 *
+	 * 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.
+	 *
+	 *
+	 * @param string|array $conds
+	 *
+	 * May be either a string containing a single condition, or an array of
+	 * conditions. If an array is given, the conditions constructed from each
+	 * element are combined with AND.
+	 *
+	 * Array elements may take one of two forms:
+	 *
+	 *   - Elements with a numeric key are interpreted as raw SQL fragments.
+	 *   - Elements with a string key are interpreted as equality conditions,
+	 *     where the key is the field name.
+	 *     - If the value of such an array element is a scalar (such as a
+	 *       string), it will be treated as data and thus quoted appropriately.
+	 *       If it is null, an IS NULL clause will be added.
+	 *     - If the value is an array, an IN (...) clause will be constructed
+	 *       from its non-null elements, and an IS NULL clause will be added
+	 *       if null is present, such that the field may match any of the
+	 *       elements in the array. The non-null elements will be quoted.
+	 *
+	 * Note that expressions are often DBMS-dependent in their syntax.
+	 * DBMS-independent wrappers are provided for constructing several types of
+	 * expression commonly used in condition queries. See:
+	 *    - DatabaseBase::buildLike()
+	 *    - DatabaseBase::conditional()
+	 *
+	 *
+	 * @param string|array $options
+	 *
+	 * Optional: Array of query options. Boolean options are specified by
+	 * including them in the array as a string value with a numeric key, for
+	 * example:
+	 *
+	 *    array( 'FOR UPDATE' )
+	 *
+	 * The supported options are:
+	 *
+	 *   - OFFSET: Skip this many rows at the start of the result set. OFFSET
+	 *     with LIMIT can theoretically be used for paging through a result set,
+	 *     but this is discouraged in MediaWiki for performance reasons.
+	 *
+	 *   - LIMIT: Integer: return at most this many rows. The rows are sorted
+	 *     and then the first rows are taken until the limit is reached. LIMIT
+	 *     is applied to a result set after OFFSET.
+	 *
+	 *   - FOR UPDATE: Boolean: lock the returned rows so that they can't be
+	 *     changed until the next COMMIT.
+	 *
+	 *   - DISTINCT: Boolean: return only unique result rows.
+	 *
+	 *   - 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: 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.
+	 *
+	 *   - USE INDEX: This may be either a string giving the index name to use
+	 *     for the query, or an array. If it is an associative array, each key
+	 *     gives the table name (or alias), each value gives the index name to
+	 *     use for that table. All strings are SQL fragments and so should be
+	 *     validated by the caller.
+	 *
+	 *   - EXPLAIN: In MySQL, this causes an EXPLAIN SELECT query to be run,
+	 *     instead of SELECT.
+	 *
+	 * And also the following boolean MySQL extensions, see the MySQL manual
+	 * for documentation:
+	 *
+	 *    - LOCK IN SHARE MODE
+	 *    - STRAIGHT_JOIN
+	 *    - HIGH_PRIORITY
+	 *    - SQL_BIG_RESULT
+	 *    - SQL_BUFFER_RESULT
+	 *    - SQL_SMALL_RESULT
+	 *    - SQL_CALC_FOUND_ROWS
+	 *    - SQL_CACHE
+	 *    - SQL_NO_CACHE
+	 *
+	 *
+	 * @param string|array $join_conds
+	 *
+	 * Optional associative array of table-specific join conditions. In the
+	 * most common case, this is unnecessary, since the join condition can be
+	 * in $conds. However, it is useful for doing a LEFT JOIN.
+	 *
+	 * The key of the array contains the table name or alias. The value is an
+	 * array with two elements, numbered 0 and 1. The first gives the type of
+	 * join, the second is an SQL fragment giving the join condition for that
+	 * table. For example:
+	 *
+	 *    array( 'page' => array( 'LEFT JOIN', 'page_latest=rev_id' ) )
+	 *
+	 * @return ResultWrapper|bool If the query returned no rows, a ResultWrapper
+	 *   with no rows in it will be returned. If there was a query error, a
+	 *   DBQueryError exception will be thrown, except if the "ignore errors"
+	 *   option was set, in which case false will be returned.
+	 */
+	public function select(
+		$table, $vars, $conds = '', $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	);
+
+	/**
+	 * The equivalent of DatabaseBase::select() except that the constructed SQL
+	 * 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 string|array $table Table name
+	 * @param string|array $vars Field names
+	 * @param string|array $conds Conditions
+	 * @param string $fname Caller function name
+	 * @param string|array $options Query options
+	 * @param string|array $join_conds Join conditions
+	 *
+	 * @return string SQL query string.
+	 * @see DatabaseBase::select()
+	 */
+	public function selectSQLText(
+		$table, $vars, $conds = '', $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	);
+
+	/**
+	 * Single row SELECT wrapper. Equivalent to DatabaseBase::select(), except
+	 * that a single row object is returned. If the query returns no rows,
+	 * false is returned.
+	 *
+	 * @param string|array $table Table name
+	 * @param string|array $vars Field names
+	 * @param array $conds Conditions
+	 * @param string $fname Caller function name
+	 * @param string|array $options Query options
+	 * @param array|string $join_conds Join conditions
+	 *
+	 * @return stdClass|bool
+	 */
+	public function selectRow( $table, $vars, $conds, $fname = __METHOD__,
+		$options = array(), $join_conds = array()
+	);
+
+	/**
+	 * Estimate the number of rows in dataset
+	 *
+	 * MySQL allows you to estimate the number of rows that would be returned
+	 * by a SELECT query, using EXPLAIN SELECT. The estimate is provided using
+	 * index cardinality statistics, and is notoriously inaccurate, especially
+	 * when large numbers of rows have recently been added or deleted.
+	 *
+	 * For DBMSs that don't support fast result size estimation, this function
+	 * will actually perform the SELECT COUNT(*).
+	 *
+	 * Takes the same arguments as DatabaseBase::select().
+	 *
+	 * @param string $table Table name
+	 * @param string $vars Unused
+	 * @param array|string $conds Filters on the table
+	 * @param string $fname Function name for profiling
+	 * @param array $options Options for select
+	 * @return int Row count
+	 */
+	public function estimateRowCount(
+		$table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array()
+	);
+
+	/**
+	 * Get the number of rows in dataset
+	 *
+	 * This is useful when trying to do COUNT(*) but with a LIMIT for performance.
+	 *
+	 * Takes the same arguments as DatabaseBase::select().
+	 *
+	 * @param string $table Table name
+	 * @param string $vars Unused
+	 * @param array|string $conds Filters on the table
+	 * @param string $fname Function name for profiling
+	 * @param array $options Options for select
+	 * @return int Row count
+	 * @since 1.24
+	 */
+	public function selectRowCount(
+		$table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array()
+	);
+
+	/**
+	 * Determines whether a field exists in a table
+	 *
+	 * @param string $table Table name
+	 * @param string $field Filed to check on that table
+	 * @param string $fname Calling function name (optional)
+	 * @return bool Whether $table has filed $field
+	 */
+	public function fieldExists( $table, $field, $fname = __METHOD__ );
+
+	/**
+	 * Determines whether an index exists
+	 * Usually throws a DBQueryError on failure
+	 * If errors are explicitly ignored, returns NULL on failure
+	 *
+	 * @param string $table
+	 * @param string $index
+	 * @param string $fname
+	 * @return bool|null
+	 */
+	public function indexExists( $table, $index, $fname = __METHOD__ );
+
+	/**
+	 * Query whether a given table exists
+	 *
+	 * @param string $table
+	 * @param string $fname
+	 * @return bool
+	 */
+	public function tableExists( $table, $fname = __METHOD__ );
+
+	/**
+	 * Determines if a given index is unique
+	 *
+	 * @param string $table
+	 * @param string $index
+	 *
+	 * @return bool
+	 */
+	public function indexUnique( $table, $index );
+
+	/**
+	 * INSERT wrapper, inserts an array into a table.
+	 *
+	 * $a may be either:
+	 *
+	 *   - A single associative array. The array keys are the field names, and
+	 *     the values are the values to insert. The values are treated as data
+	 *     and will be quoted appropriately. If NULL is inserted, this will be
+	 *     converted to a database NULL.
+	 *   - An array with numeric keys, holding a list of associative arrays.
+	 *     This causes a multi-row INSERT on DBMSs that support it. The keys in
+	 *     each subarray must be identical to each other, and in the same order.
+	 *
+	 * Usually throws a DBQueryError on failure. If errors are explicitly ignored,
+	 * returns success.
+	 *
+	 * $options is an array of options, with boolean options encoded as values
+	 * with numeric keys, in the same style as $options in
+	 * DatabaseBase::select(). Supported options are:
+	 *
+	 *   - IGNORE: Boolean: if present, duplicate key errors are ignored, and
+	 *     any rows which cause duplicate key errors are not inserted. It's
+	 *     possible to determine how many rows were successfully inserted using
+	 *     DatabaseBase::affectedRows().
+	 *
+	 * @param string $table Table name. This will be passed through
+	 *   DatabaseBase::tableName().
+	 * @param array $a Array of rows to insert
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
+	 * @param array $options Array of options
+	 *
+	 * @return bool
+	 */
+	public function insert( $table, $a, $fname = __METHOD__, $options = array() );
+
+	/**
+	 * UPDATE wrapper. Takes a condition array and a SET array.
+	 *
+	 * @param string $table Name of the table to UPDATE. This will be passed through
+	 *   DatabaseBase::tableName().
+	 * @param array $values An array of values to SET. For each array element,
+	 *   the key gives the field name, and the value gives the data to set
+	 *   that field to. The data will be quoted by DatabaseBase::addQuotes().
+	 * @param array $conds An array of conditions (WHERE). See
+	 *   DatabaseBase::select() for the details of the format of condition
+	 *   arrays. Use '*' to update all rows.
+	 * @param string $fname The function name of the caller (from __METHOD__),
+	 *   for logging and profiling.
+	 * @param array $options An array of UPDATE options, can be:
+	 *   - IGNORE: Ignore unique key conflicts
+	 *   - LOW_PRIORITY: MySQL-specific, see MySQL manual.
+	 * @return bool
+	 */
+	public function update( $table, $values, $conds, $fname = __METHOD__, $options = array() );
+
+	/**
+	 * Makes an encoded list of strings from an array
+	 *
+	 * @param array $a Containing the data
+	 * @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_OR:    ORed WHERE clause (without the WHERE)
+	 *    - 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 );
+
+	/**
+	 * Build a partial where clause from a 2-d array such as used for LinkBatch.
+	 * The keys on each level may be either integers or strings.
+	 *
+	 * @param array $data Organized as 2-d
+	 *    array(baseKeyVal => array(subKeyVal => [ignored], ...), ...)
+	 * @param string $baseKey Field name to match the base-level keys to (eg 'pl_namespace')
+	 * @param string $subKey Field name to match the sub-level keys to (eg 'pl_title')
+	 * @return string|bool SQL fragment, or false if no items in array
+	 */
+	public function makeWhereFrom2d( $data, $baseKey, $subKey );
+
+	/**
+	 * @param string $field
+	 * @return string
+	 */
+	public function bitNot( $field );
+
+	/**
+	 * @param string $fieldLeft
+	 * @param string $fieldRight
+	 * @return string
+	 */
+	public function bitAnd( $fieldLeft, $fieldRight );
+
+	/**
+	 * @param string $fieldLeft
+	 * @param string $fieldRight
+	 * @return string
+	 */
+	public function bitOr( $fieldLeft, $fieldRight );
+
+	/**
+	 * Build a concatenation list to feed into a SQL query
+	 * @param array $stringList List of raw SQL expressions; caller is
+	 *   responsible for any quoting
+	 * @return string
+	 */
+	public function buildConcat( $stringList );
+
+	/**
+	 * Build a GROUP_CONCAT or equivalent statement for a query.
+	 *
+	 * This is useful for combining a field for several rows into a single string.
+	 * NULL values will not appear in the output, duplicated values will appear,
+	 * and the resulting delimiter-separated values have no defined sort order.
+	 * Code using the results may need to use the PHP unique() or sort() methods.
+	 *
+	 * @param string $delim Glue to bind the results together
+	 * @param string|array $table Table name
+	 * @param string $field Field name
+	 * @param string|array $conds Conditions
+	 * @param string|array $join_conds Join conditions
+	 * @return string SQL text
+	 * @since 1.23
+	 */
+	public function buildGroupConcatField(
+		$delim, $table, $field, $conds = '', $join_conds = array()
+	);
+
+	/**
+	 * Change the current database
+	 *
+	 * @param string $db
+	 * @return bool Success or failure
+	 */
+	public function selectDB( $db );
+
+	/**
+	 * Get the current DB name
+	 * @return string
+	 */
+	public function getDBname();
+
+	/**
+	 * Get the server hostname or IP address
+	 * @return string
+	 */
+	public function getServer();
+
+	/**
+	 * Adds quotes and backslashes.
+	 *
+	 * @param string|Blob $s
+	 * @return string
+	 */
+	public function addQuotes( $s );
+
+	/**
+	 * LIKE statement wrapper, receives a variable-length argument list with
+	 * parts of pattern to match containing either string literals that will be
+	 * escaped or tokens returned by anyChar() or anyString(). Alternatively,
+	 * the function could be provided with an array of aforementioned
+	 * parameters.
+	 *
+	 * Example: $dbr->buildLike( 'My_page_title/', $dbr->anyString() ) returns
+	 * a LIKE clause that searches for subpages of 'My page title'.
+	 * Alternatively:
+	 *   $pattern = array( 'My_page_title/', $dbr->anyString() );
+	 *   $query .= $dbr->buildLike( $pattern );
+	 *
+	 * @since 1.16
+	 * @return string Fully built LIKE statement
+	 */
+	public function buildLike();
+
+	/**
+	 * Returns a token for buildLike() that denotes a '_' to be used in a LIKE query
+	 *
+	 * @return LikeMatch
+	 */
+	public function anyChar();
+
+	/**
+	 * Returns a token for buildLike() that denotes a '%' to be used in a LIKE query
+	 *
+	 * @return LikeMatch
+	 */
+	public function anyString();
+
+	/**
+	 * Returns an appropriately quoted sequence value for inserting a new row.
+	 * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL
+	 * subclass will return an integer, and save the value for insertId()
+	 *
+	 * Any implementation of this function should *not* involve reusing
+	 * sequence numbers created for rolled-back transactions.
+	 * See http://bugs.mysql.com/bug.php?id=30767 for details.
+	 * @param string $seqName
+	 * @return null|int
+	 */
+	public function nextSequenceValue( $seqName );
+
+	/**
+	 * REPLACE query wrapper.
+	 *
+	 * REPLACE is a very handy MySQL extension, which functions like an INSERT
+	 * except that when there is a duplicate key error, the old row is deleted
+	 * and the new row is inserted in its place.
+	 *
+	 * We simulate this with standard SQL with a DELETE followed by INSERT. To
+	 * perform the delete, we need to know what the unique indexes are so that
+	 * we know how to find the conflicting rows.
+	 *
+	 * It may be more efficient to leave off unique indexes which are unlikely
+	 * to collide. However if you do this, you run the risk of encountering
+	 * errors which wouldn't have occurred in MySQL.
+	 *
+	 * @param string $table The table to replace the row(s) in.
+	 * @param array $uniqueIndexes Is an array of indexes. Each element may be either
+	 *    a field name or an array of field names
+	 * @param array $rows Can be either a single row to insert, or multiple rows,
+	 *    in the same format as for DatabaseBase::insert()
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
+	 */
+	public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ );
+
+	/**
+	 * INSERT ON DUPLICATE KEY UPDATE wrapper, upserts an array into a table.
+	 *
+	 * This updates any conflicting rows (according to the unique indexes) using
+	 * the provided SET clause and inserts any remaining (non-conflicted) rows.
+	 *
+	 * $rows may be either:
+	 *   - A single associative array. The array keys are the field names, and
+	 *     the values are the values to insert. The values are treated as data
+	 *     and will be quoted appropriately. If NULL is inserted, this will be
+	 *     converted to a database NULL.
+	 *   - An array with numeric keys, holding a list of associative arrays.
+	 *     This causes a multi-row INSERT on DBMSs that support it. The keys in
+	 *     each subarray must be identical to each other, and in the same order.
+	 *
+	 * It may be more efficient to leave off unique indexes which are unlikely
+	 * to collide. However if you do this, you run the risk of encountering
+	 * errors which wouldn't have occurred in MySQL.
+	 *
+	 * Usually throws a DBQueryError on failure. If errors are explicitly ignored,
+	 * returns success.
+	 *
+	 * @since 1.22
+	 *
+	 * @param string $table Table name. This will be passed through DatabaseBase::tableName().
+	 * @param array $rows A single row or list of rows to insert
+	 * @param array $uniqueIndexes List of single field names or field name tuples
+	 * @param array $set An array of values to SET. For each array element, the
+	 *   key gives the field name, and the value gives the data to set that
+	 *   field to. The data will be quoted by DatabaseBase::addQuotes().
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
+	 * @throws Exception
+	 * @return bool
+	 */
+	public function upsert(
+		$table, array $rows, array $uniqueIndexes, array $set, $fname = __METHOD__
+	);
+
+	/**
+	 * DELETE where the condition is a join.
+	 *
+	 * MySQL overrides this to use a multi-table DELETE syntax, in other databases
+	 * we use sub-selects
+	 *
+	 * For safety, an empty $conds will not delete everything. If you want to
+	 * delete all rows where the join condition matches, set $conds='*'.
+	 *
+	 * DO NOT put the join condition in $conds.
+	 *
+	 * @param string $delTable The table to delete from.
+	 * @param string $joinTable The other table.
+	 * @param string $delVar The variable to join on, in the first table.
+	 * @param string $joinVar The variable to join on, in the second table.
+	 * @param array $conds Condition array of field names mapped to variables,
+	 *   ANDed together in the WHERE clause
+	 * @param string $fname Calling function name (use __METHOD__) for logs/profiling
+	 * @throws DBUnexpectedError
+	 */
+	public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
+		$fname = __METHOD__
+	);
+
+	/**
+	 * DELETE query wrapper.
+	 *
+	 * @param array $table Table name
+	 * @param string|array $conds Array of conditions. See $conds in DatabaseBase::select()
+	 *   for the format. Use $conds == "*" to delete all rows
+	 * @param string $fname Name of the calling function
+	 * @throws DBUnexpectedError
+	 * @return bool|ResultWrapper
+	 */
+	public function delete( $table, $conds, $fname = __METHOD__ );
+
+	/**
+	 * INSERT SELECT wrapper. Takes data from a SELECT query and inserts it
+	 * into another table.
+	 *
+	 * @param string $destTable The table name to insert into
+	 * @param string|array $srcTable May be either a table name, or an array of table names
+	 *    to include in a join.
+	 *
+	 * @param array $varMap Must be an associative array of the form
+	 *    array( 'dest1' => 'source1', ...). Source items may be literals
+	 *    rather than field names, but strings should be quoted with
+	 *    DatabaseBase::addQuotes()
+	 *
+	 * @param array $conds Condition array. See $conds in DatabaseBase::select() for
+	 *    the details of the format of condition arrays. May be "*" to copy the
+	 *    whole table.
+	 *
+	 * @param string $fname The function name of the caller, from __METHOD__
+	 *
+	 * @param array $insertOptions Options for the INSERT part of the query, see
+	 *    DatabaseBase::insert() for details.
+	 * @param array $selectOptions Options for the SELECT part of the query, see
+	 *    DatabaseBase::select() for details.
+	 *
+	 * @return ResultWrapper
+	 */
+	public function insertSelect( $destTable, $srcTable, $varMap, $conds,
+		$fname = __METHOD__,
+		$insertOptions = array(), $selectOptions = array()
+	);
+
+	/**
+	 * Returns true if current database backend supports ORDER BY or LIMIT for separate subqueries
+	 * within the UNION construct.
+	 * @return bool
+	 */
+	public function unionSupportsOrderAndLimit();
+
+	/**
+	 * Construct a UNION query
+	 * This is used for providing overload point for other DB abstractions
+	 * not compatible with the MySQL syntax.
+	 * @param array $sqls SQL statements to combine
+	 * @param bool $all Use UNION ALL
+	 * @return string SQL fragment
+	 */
+	public function unionQueries( $sqls, $all );
+
+	/**
+	 * Returns an SQL expression for a simple conditional. This doesn't need
+	 * to be overridden unless CASE isn't supported in your DBMS.
+	 *
+	 * @param string|array $cond SQL expression which will result in a boolean value
+	 * @param string $trueVal SQL expression to return if true
+	 * @param string $falseVal SQL expression to return if false
+	 * @return string SQL fragment
+	 */
+	public function conditional( $cond, $trueVal, $falseVal );
+
+	/**
+	 * Returns a comand for str_replace function in SQL query.
+	 * Uses REPLACE() in MySQL
+	 *
+	 * @param string $orig Column to modify
+	 * @param string $old Column to seek
+	 * @param string $new Column to replace with
+	 *
+	 * @return string
+	 */
+	public function strreplace( $orig, $old, $new );
+
+	/**
+	 * Determines how long the server has been up
+	 * STUB
+	 *
+	 * @return int
+	 */
+	public function getServerUptime();
+
+	/**
+	 * Determines if the last failure was due to a deadlock
+	 * STUB
+	 *
+	 * @return bool
+	 */
+	public function wasDeadlock();
+
+	/**
+	 * Determines if the last failure was due to a lock timeout
+	 * STUB
+	 *
+	 * @return bool
+	 */
+	public function wasLockTimeout();
+
+	/**
+	 * Determines if the last query error was something that should be dealt
+	 * with by pinging the connection and reissuing the query.
+	 * STUB
+	 *
+	 * @return bool
+	 */
+	public function wasErrorReissuable();
+
+	/**
+	 * Determines if the last failure was due to the database being read-only.
+	 * STUB
+	 *
+	 * @return bool
+	 */
+	public function wasReadOnlyError();
+
+	/**
+	 * Wait for the slave to catch up to a given master position.
+	 *
+	 * @param DBMasterPos $pos
+	 * @param int $timeout The maximum number of seconds to wait for
+	 *   synchronisation
+	 * @return int 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.
+	 */
+	public function masterPosWait( DBMasterPos $pos, $timeout );
+
+	/**
+	 * Get the replication position of this slave
+	 *
+	 * @return DBMasterPos|bool False if this is not a slave.
+	 */
+	public function getSlavePos();
+
+	/**
+	 * Get the position of this master
+	 *
+	 * @return DBMasterPos|bool False if this is not a master
+	 */
+	public function getMasterPos();
+
+	/**
+	 * 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.
+	 * Queries in the function will run in AUTO-COMMIT mode unless there are begin() calls.
+	 * Callbacks must commit any transactions that they begin.
+	 *
+	 * This is useful for updates to different systems or when separate transactions are needed.
+	 * For example, one might want to enqueue jobs into a system outside the database, but only
+	 * after the database is updated so that the jobs will see the data when they actually run.
+	 * It can also be used for updates that easily cause deadlocks if locks are held too long.
+	 *
+	 * @param callable $callback
+	 * @since 1.20
+	 */
+	public function onTransactionIdle( $callback );
+
+	/**
+	 * Run an anonymous function before the current transaction commits or now if there is none.
+	 * If there is a transaction and it is rolled back, then the callback is cancelled.
+	 * Callbacks must not start nor commit any transactions.
+	 *
+	 * This is useful for updates that easily cause deadlocks if locks are held too long
+	 * but where atomicity is strongly desired for these updates and some related updates.
+	 *
+	 * @param callable $callback
+	 * @since 1.22
+	 */
+	public function onTransactionPreCommitOrIdle( $callback );
+
+	/**
+	 * Begin an atomic section of statements
+	 *
+	 * If a transaction has been started already, just keep track of the given
+	 * section name to make sure the transaction is not committed pre-maturely.
+	 * This function can be used in layers (with sub-sections), so use a stack
+	 * to keep track of the different atomic sections. If there is no transaction,
+	 * start one implicitly.
+	 *
+	 * The goal of this function is to create an atomic section of SQL queries
+	 * without having to start a new transaction if it already exists.
+	 *
+	 * Atomic sections are more strict than transactions. With transactions,
+	 * attempting to begin a new transaction when one is already running results
+	 * in MediaWiki issuing a brief warning and doing an implicit commit. All
+	 * atomic levels *must* be explicitly closed using DatabaseBase::endAtomic(),
+	 * and any database transactions cannot be began or committed until all atomic
+	 * levels are closed. There is no such thing as implicitly opening or closing
+	 * an atomic section.
+	 *
+	 * @since 1.23
+	 * @param string $fname
+	 * @throws DBError
+	 */
+	public function startAtomic( $fname = __METHOD__ );
+
+	/**
+	 * Ends an atomic section of SQL statements
+	 *
+	 * Ends the next section of atomic SQL statements and commits the transaction
+	 * if necessary.
+	 *
+	 * @since 1.23
+	 * @see DatabaseBase::startAtomic
+	 * @param string $fname
+	 * @throws DBError
+	 */
+	public function endAtomic( $fname = __METHOD__ );
+
+	/**
+	 * 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 string $fname
+	 * @throws DBError
+	 */
+	public function begin( $fname = __METHOD__ );
+
+	/**
+	 * Commits a transaction previously started using begin().
+	 * If no transaction is in progress, a warning is issued.
+	 *
+	 * Nesting of transactions is not supported.
+	 *
+	 * @param string $fname
+	 * @param string $flush Flush flag, set to 'flush' to disable warnings about
+	 *   explicitly committing implicit transactions, or calling commit when no
+	 *   transaction is in progress. This will silently break any ongoing
+	 *   explicit transaction. Only set the flush flag if you are sure that it
+	 *   is safe to ignore these warnings in your context.
+	 * @throws DBUnexpectedError
+	 */
+	public function commit( $fname = __METHOD__, $flush = '' );
+
+	/**
+	 * Rollback a transaction previously started using begin().
+	 * If no transaction is in progress, a warning is issued.
+	 *
+	 * No-op on non-transactional databases.
+	 *
+	 * @param string $fname
+	 * @param string $flush Flush flag, set to 'flush' to disable warnings about
+	 *   calling rollback when no transaction is in progress. This will silently
+	 *   break any ongoing explicit transaction. Only set the flush flag if you
+	 *   are sure that it is safe to ignore these warnings in your context.
+	 * @throws DBUnexpectedError
+	 * @since 1.23 Added $flush parameter
+	 */
+	public function rollback( $fname = __METHOD__, $flush = '' );
+
+	/**
+	 * List all tables on the database
+	 *
+	 * @param string $prefix Only show tables with this prefix, e.g. mw_
+	 * @param string $fname Calling function name
+	 * @throws MWException
+	 * @return array
+	 */
+	public function listTables( $prefix = null, $fname = __METHOD__ );
+
+	/**
+	 * Convert a timestamp in one of the formats accepted by wfTimestamp()
+	 * to the format used for inserting into timestamp fields in this DBMS.
+	 *
+	 * The result is unquoted, and needs to be passed through addQuotes()
+	 * before it can be included in raw SQL.
+	 *
+	 * @param string|int $ts
+	 *
+	 * @return string
+	 */
+	public function timestamp( $ts = 0 );
+
+	/**
+	 * Convert a timestamp in one of the formats accepted by wfTimestamp()
+	 * to the format used for inserting into timestamp fields in this DBMS. If
+	 * NULL is input, it is passed through, allowing NULL values to be inserted
+	 * into timestamp fields.
+	 *
+	 * The result is unquoted, and needs to be passed through addQuotes()
+	 * before it can be included in raw SQL.
+	 *
+	 * @param string|int $ts
+	 *
+	 * @return string
+	 */
+	public function timestampOrNull( $ts = null );
+
+	/**
+	 * Take the result from a query, and wrap it in a ResultWrapper if
+	 * necessary. Boolean values are passed through as is, to indicate success
+	 * of write queries or failure.
+	 *
+	 * Once upon a time, DatabaseBase::query() returned a bare MySQL result
+	 * resource, and it was necessary to call this function to convert it to
+	 * a wrapper. Nowadays, raw database objects are never exposed to external
+	 * callers, so this is unnecessary in external code. For compatibility with
+	 * old code, ResultWrapper objects are passed through unaltered.
+	 *
+	 * @param bool|ResultWrapper|resource $result
+	 * @return bool|ResultWrapper
+	 */
+	public function resultObject( $result );
+
+	/**
+	 * Ping the server and try to reconnect if it there is no connection
+	 *
+	 * @return bool Success or failure
+	 */
+	public function ping();
+
+	/**
+	 * Get slave lag. Currently supported only by MySQL.
+	 *
+	 * Note that this function will generate a fatal error on many
+	 * installations. Most callers should use LoadBalancer::safeGetLag()
+	 * instead.
+	 *
+	 * @return int Database replication lag in seconds
+	 */
+	public function getLag();
+
+	/**
+	 * Return the maximum number of items allowed in a list, or 0 for unlimited.
+	 *
+	 * @return int
+	 */
+	public function maxListLen();
+
+	/**
+	 * Some DBMSs have a special format for inserting into blob fields, they
+	 * don't allow simple quoted strings to be inserted. To insert into such
+	 * a field, pass the data through this function before passing it to
+	 * DatabaseBase::insert().
+	 *
+	 * @param string $b
+	 * @return string
+	 */
+	public function encodeBlob( $b );
+
+	/**
+	 * Some DBMSs return a special placeholder object representing blob fields
+	 * in result objects. Pass the object through this function to return the
+	 * original string.
+	 *
+	 * @param string|Blob $b
+	 * @return string
+	 */
+	public function decodeBlob( $b );
+
+	/**
+	 * 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
+	 *                     full-wiki dumps, where a single query reads out over
+	 *                     hours or days.
+	 *
+	 * @param array $options
+	 * @return void
+	 */
+	public function setSessionOptions( array $options );
+
+	/**
+	 * Set variables to be used in sourceFile/sourceStream, in preference to the
+	 * 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 bool|array $vars Mapping variable name to value.
+	 */
+	public function setSchemaVars( $vars );
+
+	/**
+	 * Check to see if a named lock is available (non-blocking)
+	 *
+	 * @param string $lockName Name of lock to poll
+	 * @param string $method Name of method calling us
+	 * @return bool
+	 * @since 1.20
+	 */
+	public function lockIsFree( $lockName, $method );
+
+	/**
+	 * Acquire a named lock
+	 *
+	 * Named locks are not related to transactions
+	 *
+	 * @param string $lockName Name of lock to aquire
+	 * @param string $method Name of method calling us
+	 * @param int $timeout
+	 * @return bool
+	 */
+	public function lock( $lockName, $method, $timeout = 5 );
+
+	/**
+	 * Release a lock
+	 *
+	 * Named locks are not related to transactions
+	 *
+	 * @param string $lockName Name of lock to release
+	 * @param string $method Name of method calling us
+	 *
+	 * @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
+	 */
+	public function unlock( $lockName, $method );
+
+	/**
+	 * Check to see if a named lock used by lock() use blocking queues
+	 *
+	 * @return bool
+	 * @since 1.26
+	 */
+	public function namedLocksEnqueue();
+
+	/**
+	 * Find out when 'infinity' is. Most DBMSes support this. This is a special
+	 * keyword for timestamps in PostgreSQL, and works with CHAR(14) as well
+	 * because "i" sorts after all numbers.
+	 *
+	 * @return string
+	 */
+	public function getInfinity();
+
+	/**
+	 * Encode an expiry time into the DBMS dependent format
+	 *
+	 * @param string $expiry Timestamp for expiry, or the 'infinity' string
+	 * @return string
+	 */
+	public function encodeExpiry( $expiry );
+
+	/**
+	 * Decode an expiry time into a DBMS independent format
+	 *
+	 * @param string $expiry DB timestamp field value for expiry
+	 * @param int $format TS_* constant, defaults to TS_MW
+	 * @return string
+	 */
+	public function decodeExpiry( $expiry, $format = TS_MW );
+
+	/**
+	 * Allow or deny "big selects" for this session only. This is done by setting
+	 * the sql_big_selects session variable.
+	 *
+	 * This is a MySQL-specific feature.
+	 *
+	 * @param bool|string $value True for allow, false for deny, or "default" to
+	 *   restore the initial value
+	 */
+	public function setBigSelects( $value = true );
+}