Wikimedia\Rdbms\IDatabase Interface Reference

Basic database interface for live and lazy-loaded relation database handles. More...

Inheritance diagram for Wikimedia\Rdbms\IDatabase:

Public Member Functions
	addQuotes ( $s)
	Adds quotes and backslashes. More...
	affectedRows ()
	Get the number of rows affected by the last write query. More...
	aggregateValue ( $valuedata, $valuename='value')
	Return aggregated value alias. More...
	anyChar ()
	Returns a token for buildLike() that denotes a '_' to be used in a LIKE query. More...
	anyString ()
	Returns a token for buildLike() that denotes a '' to be used in a LIKE query. More...
	begin ( $fname=__METHOD__, $mode=self::TRANSACTION_EXPLICIT)
	Begin a transaction. More...
	bitAnd ( $fieldLeft, $fieldRight)
	bitNot ( $field)
	bitOr ( $fieldLeft, $fieldRight)
	bufferResults ( $buffer=null)
	Turns buffering of SQL result sets on (true) or off (false). More...
	buildConcat ( $stringList)
	Build a concatenation list to feed into a SQL query. More...
	buildGroupConcatField ( $delim, $table, $field, $conds='', $join_conds=[])
	Build a GROUP_CONCAT or equivalent statement for a query. More...
	buildLike ()
	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(). More...
	buildStringCast ( $field)
	clearFlag ( $flag, $remember=self::REMEMBER_NOTHING)
	Clear a flag for this connection. More...
	close ()
	Closes a database connection. More...
	commit ( $fname=__METHOD__, $flush='')
	Commits a transaction previously started using begin(). More...
	conditional ( $cond, $trueVal, $falseVal)
	Returns an SQL expression for a simple conditional. More...
	databasesAreIndependent ()
	Returns true if DBs are assumed to be on potentially different servers. More...
	dataSeek ( $res, $row)
	Change the position of the cursor in a result object. More...
	dbSchema ( $schema=null)
	Get/set the db schema. More...
	decodeBlob ( $b)
	Some DBMSs return a special placeholder object representing blob fields in result objects. More...
	decodeExpiry ( $expiry, $format=TS_MW)
	Decode an expiry time into a DBMS independent format. More...
	delete ( $table, $conds, $fname=__METHOD__)
	DELETE query wrapper. More...
	deleteJoin ( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname=__METHOD__)
	DELETE where the condition is a join. More...
	doAtomicSection ( $fname, callable $callback)
	Run a callback to do an atomic set of updates for this database. More...
	doneWrites ()
	Returns true if the connection may have been used for write queries. More...
	encodeBlob ( $b)
	Some DBMSs have a special format for inserting into blob fields, they don't allow simple quoted strings to be inserted. More...
	encodeExpiry ( $expiry)
	Encode an expiry time into the DBMS dependent format. More...
	endAtomic ( $fname=__METHOD__)
	Ends an atomic section of SQL statements. More...
	estimateRowCount ( $table, $vars=' *', $conds='', $fname=__METHOD__, $options=[])
	Estimate the number of rows in dataset. More...
	explicitTrxActive ()
	fetchObject ( $res)
	Fetch the next row from the given result object, in object form. More...
	fetchRow ( $res)
	Fetch the next row from the given result object, in associative array form. More...
	fieldExists ( $table, $field, $fname=__METHOD__)
	Determines whether a field exists in a table. More...
	fieldInfo ( $table, $field)
	mysql_fetch_field() wrapper Returns false if the field doesn't exist More...
	fieldName ( $res, $n)
	Get a field name in a result object. More...
	flushSnapshot ( $fname=__METHOD__)
	Commit any transaction but error out if writes or callbacks are pending. More...
	freeResult ( $res)
	Free a result object returned by query() or select(). More...
	getDBname ()
	Get the current DB name. More...
	getDomainID ()
	getFlag ( $flag)
	Returns a boolean whether the flag $flag is set for this connection. More...
	getInfinity ()
	Find out when 'infinity' is. More...
	getLag ()
	Get replica DB lag. More...
	getLBInfo ( $name=null)
	Get properties passed down from the server info array of the load balancer. More...
	getMasterPos ()
	Get the position of this master. More...
	getReplicaPos ()
	Get the replication position of this replica DB. More...
	getScopedLockAndFlush ( $lockKey, $fname, $timeout)
	Acquire a named lock, flush any transaction, and return an RAII style unlocker object. More...
	getServer ()
	Get the server hostname or IP address. More...
	getServerInfo ()
	A string describing the current software version, and possibly other details in a user-friendly way. More...
	getServerUptime ()
	Determines how long the server has been up. More...
	getServerVersion ()
	A string describing the current software version, like from mysql_get_server_info(). More...
	getSessionLagStatus ()
	Get the replica DB lag when the current transaction started or a general lag estimate if not transaction is active. More...
	getSoftwareLink ()
	Returns a wikitext link to the DB's website, e.g., return "[https://www.mysql.com/ MySQL]"; Should at least contain plain text, if for some reason your database has no website. More...
	getType ()
	Get the type of the DBMS, as it appears in $wgDBtype. More...
	getWikiID ()
	Alias for getDomainID() More...
	implicitGroupby ()
	Returns true if this database does an implicit sort when doing GROUP BY. More...
	implicitOrderby ()
	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. More...
	indexExists ( $table, $index, $fname=__METHOD__)
	Determines whether an index exists Usually throws a DBQueryError on failure If errors are explicitly ignored, returns NULL on failure. More...
	indexUnique ( $table, $index)
	Determines if a given index is unique. More...
	insert ( $table, $a, $fname=__METHOD__, $options=[])
	INSERT wrapper, inserts an array into a table. More...
	insertId ()
	Get the inserted value of an auto-increment row. More...
	insertSelect ( $destTable, $srcTable, $varMap, $conds, $fname=__METHOD__, $insertOptions=[], $selectOptions=[], $selectJoinConds=[])
	INSERT SELECT wrapper. More...
	isOpen ()
	Is a connection to the database open? More...
	isReadOnly ()
	lastDoneWrites ()
	Returns the last time the connection may have been used for write queries. More...
	lastErrno ()
	Get the last error number. More...
	lastError ()
	Get a description of the last error. More...
	lastQuery ()
	Return the last query that went through IDatabase::query() More...
	listTables ( $prefix=null, $fname=__METHOD__)
	List all tables on the database. More...
	lock ( $lockName, $method, $timeout=5)
	Acquire a named lock. More...
	lockIsFree ( $lockName, $method)
	Check to see if a named lock is available (non-blocking) More...
	makeList ( $a, $mode=self::LIST_COMMA)
	Makes an encoded list of strings from an array. More...
	makeWhereFrom2d ( $data, $baseKey, $subKey)
	Build a partial where clause from a 2-d array such as used for LinkBatch. More...
	masterPosWait (DBMasterPos $pos, $timeout)
	Wait for the replica DB to catch up to a given master position. More...
	maxListLen ()
	Return the maximum number of items allowed in a list, or 0 for unlimited. More...
	namedLocksEnqueue ()
	Check to see if a named lock used by lock() use blocking queues. More...
	nextSequenceValue ( $seqName)
	Deprecated method, calls should be removed. More...
	numFields ( $res)
	Get the number of fields in a result object. More...
	numRows ( $res)
	Get the number of rows in a result object. More...
	onTransactionIdle (callable $callback, $fname=__METHOD__)
	Run a callback as soon as there is no transaction pending. More...
	onTransactionPreCommitOrIdle (callable $callback, $fname=__METHOD__)
	Run a callback before the current transaction commits or now if there is none. More...
	onTransactionResolution (callable $callback, $fname=__METHOD__)
	Run a callback as soon as the current transaction commits or rolls back. More...
	open ( $server, $user, $password, $dbName)
	Open a connection to the database. More...
	pendingWriteCallers ()
	Get the list of method names that did write queries for this transaction. More...
	pendingWriteQueryDuration ( $type=self::ESTIMATE_TOTAL)
	Get the time spend running write queries for this transaction. More...
	pendingWriteRowsAffected ()
	Get the number of affected rows from pending write queries. More...
	ping (&$rtt=null)
	Ping the server and try to reconnect if it there is no connection. More...
	query ( $sql, $fname=__METHOD__, $tempIgnore=false)
	Run an SQL query and return the result. More...
	replace ( $table, $uniqueIndexes, $rows, $fname=__METHOD__)
	REPLACE query wrapper. More...
	reportConnectionError ( $error='Unknown error')
	reportQueryError ( $error, $errno, $sql, $fname, $tempIgnore=false)
	Report a query error. More...
	restoreFlags ( $state=self::RESTORE_PRIOR)
	Restore the flags to their prior state before the last setFlag/clearFlag call. More...
	rollback ( $fname=__METHOD__, $flush='')
	Rollback a transaction previously started using begin(). More...
	select ( $table, $vars, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
	Execute a SELECT query constructed using the various parameters provided. More...
	selectDB ( $db)
	Change the current database. More...
	selectField ( $table, $var, $cond='', $fname=__METHOD__, $options=[], $join_conds=[])
	A SELECT wrapper which returns a single field from a single result row. More...
	selectFieldValues ( $table, $var, $cond='', $fname=__METHOD__, $options=[], $join_conds=[])
	A SELECT wrapper which returns a list of single field values from result rows. More...
	selectRow ( $table, $vars, $conds, $fname=__METHOD__, $options=[], $join_conds=[])
	Single row SELECT wrapper. More...
	selectRowCount ( $tables, $vars=' *', $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
	Get the number of rows in dataset. More...
	selectSQLText ( $table, $vars, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
	The equivalent of IDatabase::select() except that the constructed SQL is returned, instead of being immediately executed. More...
	serverIsReadOnly ()
	setBigSelects ( $value=true)
	Allow or deny "big selects" for this session only. More...
	setFlag ( $flag, $remember=self::REMEMBER_NOTHING)
	Set a flag for this connection. More...
	setLazyMasterHandle (IDatabase $conn)
	Set a lazy-connecting DB handle to the master DB (for replication status purposes) More...
	setLBInfo ( $name, $value=null)
	Set the LB info array, or a member of it. More...
	setSchemaVars ( $vars)
	Set variables to be used in sourceFile/sourceStream, in preference to the ones in $GLOBALS. More...
	setSessionOptions (array $options)
	Override database's default behavior. More...
	setTableAliases (array $aliases)
	Make certain table names use their own database, schema, and table prefix when passed into SQL queries pre-escaped and without a qualified database name. More...
	setTransactionListener ( $name, callable $callback=null)
	Run a callback each time any transaction commits or rolls back. More...
	startAtomic ( $fname=__METHOD__)
	Begin an atomic section of statements. More...
	strreplace ( $orig, $old, $new)
	Returns a command for str_replace function in SQL query. More...
	tableExists ( $table, $fname=__METHOD__)
	Query whether a given table exists. More...
	tablePrefix ( $prefix=null)
	Get/set the table prefix. More...
	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. More...
	timestampOrNull ( $ts=null)
	Convert a timestamp in one of the formats accepted by wfTimestamp() to the format used for inserting into timestamp fields in this DBMS. More...
	trxLevel ()
	Gets the current transaction level. More...
	trxTimestamp ()
	Get the UNIX timestamp of the time that the transaction was established. More...
	unionConditionPermutations ( $table, $vars, array $permute_conds, $extra_conds='', $fname=__METHOD__, $options=[], $join_conds=[])
	Construct a UNION query for permutations of conditions. More...
	unionQueries ( $sqls, $all)
	Construct a UNION query This is used for providing overload point for other DB abstractions not compatible with the MySQL syntax. More...
	unionSupportsOrderAndLimit ()
	Returns true if current database backend supports ORDER BY or LIMIT for separate subqueries within the UNION construct. More...
	unlock ( $lockName, $method)
	Release a lock. More...
	update ( $table, $values, $conds, $fname=__METHOD__, $options=[])
	UPDATE wrapper. More...
	upsert ( $table, array $rows, array $uniqueIndexes, array $set, $fname=__METHOD__)
	INSERT ON DUPLICATE KEY UPDATE wrapper, upserts an array into a table. More...
	wasDeadlock ()
	Determines if the last failure was due to a deadlock. More...
	wasErrorReissuable ()
	Determines if the last query error was due to a dropped connection and should be dealt with by pinging the connection and reissuing the query. More...
	wasLockTimeout ()
	Determines if the last failure was due to a lock timeout. More...
	wasReadOnlyError ()
	Determines if the last failure was due to the database being read-only. More...
	writesOrCallbacksPending ()
	Returns true if there is a transaction open with possible write queries or transaction pre-commit/idle callbacks waiting on it to finish. More...
	writesPending ()

Detailed Description

Basic database interface for live and lazy-loaded relation database handles.

Note

: IDatabase and DBConnRef should be updated to reflect any changes

Definition at line 40 of file IDatabase.php.

Member Function Documentation

addQuotes()

Wikimedia\Rdbms\IDatabase::addQuotes

(

$s

)

Adds quotes and backslashes.

Parameters

string | int | null | bool | Blob

$s

Returns

string|int

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMssql, DatabaseOracle, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

Referenced by PopulateRecentChangesSource\buildUpdateCondition(), DBFileJournal\doGetChangeEntries(), DBFileJournal\doGetPositionAtTime(), DBFileJournal\doPurgeOldLogs(), RefreshImageMetadata\execute(), RefreshImageMetadata\getConditions(), WatchedItemQueryService\getFromUntilTargetConds(), WatchedItemQueryService\getStartEndConds(), WatchedItemQueryService\getStartFromConds(), WANCacheReapUpdate\getTitleChangeEvents(), WatchedItemQueryService\getUserRelatedConds(), WatchedItemStore\getVisitingWatchersCondition(), WatchedItemQueryService\getWatchedItemsWithRCInfoQueryConds(), UserGroupMembership\insert(), Title\invalidateCache(), PurgeJobUtils\invalidatePages(), PopulateContentModel\populatePage(), PopulateContentModel\populateRevisionOrArchive(), UserGroupMembership\purgeExpired(), Block\purgeExpired(), and Title\purgeExpiredRestrictions().

affectedRows()

Wikimedia\Rdbms\IDatabase::affectedRows

(

)

Get the number of rows affected by the last write query.

See also

https://secure.php.net/mysql_affected_rows

Returns

int

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DBConnRef, Wikimedia\Rdbms\DatabaseMysqli, Wikimedia\Rdbms\DatabaseMysql, and FakeDatabaseMysqlBase.

Referenced by UserGroupMembership\delete(), Wikimedia\Rdbms\Database\doProfiledQuery(), UserGroupMembership\insert(), MigrateComments\loadCommentIDs(), and Wikimedia\Rdbms\Database\updateTrxWriteQueryTime().

aggregateValue()

Wikimedia\Rdbms\IDatabase::aggregateValue	(		$valuedata,
			$valuename = 'value'
	)

Return aggregated value alias.

Parameters

array	$valuedata
string	$valuename

Returns

string

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

anyChar()

Wikimedia\Rdbms\IDatabase::anyChar

(

)

Returns a token for buildLike() that denotes a '_' to be used in a LIKE query.

Returns

LikeMatch

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

anyString()

Wikimedia\Rdbms\IDatabase::anyString

(

)

Returns a token for buildLike() that denotes a '' to be used in a LIKE query.

Returns

LikeMatch

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by RefreshImageMetadata\getConditions().

begin()

Wikimedia\Rdbms\IDatabase::begin	(		$fname = __METHOD__,
			$mode = self::TRANSACTION_EXPLICIT
	)

Begin a transaction.

If a transaction is already in progress, that transaction will be committed before the new transaction is started.

Only call this from code with outer transcation scope. See https://www.mediawiki.org/wiki/Database_transactions for details. Nesting of transactions is not supported.

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.

Parameters

string	$fname	Calling function name
string	$mode	A situationally valid IDatabase::TRANSACTION_* constant [optional]

Exceptions

DBError

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by DatabaseTest\badLockingMethodExplicit(), and Maintenance\beginTransaction().

bitAnd()

Wikimedia\Rdbms\IDatabase::bitAnd	(		$fieldLeft,
			$fieldRight
	)

Parameters

string	$fieldLeft
string	$fieldRight

Returns

string

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

Referenced by WatchedItemQueryService\getExtraDeletedPageLogEntryRelatedCond(), and WatchedItemQueryService\getUserRelatedConds().

bitNot()

Wikimedia\Rdbms\IDatabase::bitNot

(

$field

)

Parameters

string

$field

Returns

string

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

bitOr()

Wikimedia\Rdbms\IDatabase::bitOr	(		$fieldLeft,
			$fieldRight
	)

Parameters

string	$fieldLeft
string	$fieldRight

Returns

string

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

bufferResults()

Wikimedia\Rdbms\IDatabase::bufferResults

(

$buffer = null

)

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 Database functions while you are reading an unbuffered query result from a normal Database 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.

Parameters

null | bool

$buffer

Returns

null|bool The previous value of the flag

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

buildConcat()

Wikimedia\Rdbms\IDatabase::buildConcat

(

$stringList

)

Build a concatenation list to feed into a SQL query.

Parameters

array

$stringList

List of raw SQL expressions; caller is responsible for any quoting

Returns

string

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

buildGroupConcatField()

Wikimedia\Rdbms\IDatabase::buildGroupConcatField	(		$delim,
			$table,
			$field,
			$conds = '',
			$join_conds = []
	)

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.

Parameters

string	$delim	Glue to bind the results together
string | array	$table	Table name
string	$field	Field name
string | array	$conds	Conditions
string | array	$join_conds	Join conditions

Returns

string SQL text

Since

1.23

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

buildLike()

Wikimedia\Rdbms\IDatabase::buildLike

(

)

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 = [ 'My_page_title/', $dbr->anyString() ]; $query .= $dbr->buildLike( $pattern );

Since

1.16

Returns

string Fully built LIKE statement

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by RefreshImageMetadata\getConditions().

buildStringCast()

Wikimedia\Rdbms\IDatabase::buildStringCast

(

$field

)

Parameters

string

$field

Field or column to cast

Returns

string

Since

1.28

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

clearFlag()

Wikimedia\Rdbms\IDatabase::clearFlag	(		$flag,
			$remember = self::REMEMBER_NOTHING
	)

Clear a flag for this connection.

Parameters

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
string	$remember	IDatabase::REMEMBER_* constant [default: REMEMBER_NOTHING]

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

close()

Wikimedia\Rdbms\IDatabase::close

(

)

Closes a database connection.

if it is open : commits any open transactions

Exceptions

DBError

Returns

bool Operation success. true if already closed.

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\closeAll(), and Wikimedia\Rdbms\LoadBalancer\closeConnection().

commit()

Wikimedia\Rdbms\IDatabase::commit	(		$fname = __METHOD__,
			$flush = ''
	)

Commits a transaction previously started using begin().

If no transaction is in progress, a warning is issued.

Only call this from code with outer transcation scope. See https://www.mediawiki.org/wiki/Database_transactions for details. Nesting of transactions is not supported.

Parameters

string	$fname
string	$flush	Flush flag, set to situationally valid IDatabase::FLUSHING_* constant to disable warnings about explicitly committing implicit transactions, or calling commit when no transaction is in progress.

This will trigger an exception if there is an ongoing explicit transaction.

Only set the flush flag if you are sure that these warnings are not applicable, and no explicit transactions are open.

Exceptions

DBUnexpectedError

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\commitAll(), Wikimedia\Rdbms\LoadBalancer\commitMasterChanges(), and Maintenance\commitTransaction().

conditional()

Wikimedia\Rdbms\IDatabase::conditional	(		$cond,
			$trueVal,
			$falseVal
	)

Returns an SQL expression for a simple conditional.

This doesn't need to be overridden unless CASE isn't supported in your DBMS.

Parameters

string | array	$cond	SQL expression which will result in a boolean value
string	$trueVal	SQL expression to return if true
string	$falseVal	SQL expression to return if false

Returns

string SQL fragment

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

databasesAreIndependent()

Wikimedia\Rdbms\IDatabase::databasesAreIndependent

(

)

Returns true if DBs are assumed to be on potentially different servers.

In systems like mysql/mariadb, different databases can easily be referenced on a single connection merely by name, even in a single query via JOIN. On the other hand, Postgres treats databases as fully separate, only allowing mechanisms like postgres_fdw to effectively "mount" foreign DBs. This is true even among DBs on the same server.

Returns

bool

Since

1.29

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DBConnRef, and Wikimedia\Rdbms\DatabasePostgres.

dataSeek()

Wikimedia\Rdbms\IDatabase::dataSeek	(		$res,
			$row
	)

Change the position of the cursor in a result object.

See also

https://secure.php.net/mysql_data_seek

Parameters

mixed	$res	A SQL result
int	$row

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

dbSchema()

Wikimedia\Rdbms\IDatabase::dbSchema

(

$schema = null

)

Get/set the db schema.

Parameters

string

$schema

The database schema to set, or omitted to leave it unchanged.

Returns

string The previous db schema.

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

decodeBlob()

Wikimedia\Rdbms\IDatabase::decodeBlob

(

$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.

Parameters

string | Blob

$b

Returns

string

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseSqlite, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

decodeExpiry()

Wikimedia\Rdbms\IDatabase::decodeExpiry	(		$expiry,
			$format = TS_MW
	)

Decode an expiry time into a DBMS independent format.

Parameters

string	$expiry	DB timestamp field value for expiry
int	$format	TS_* constant, defaults to TS_MW

Returns

string

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

delete()

Wikimedia\Rdbms\IDatabase::delete	(		$table,
			$conds,
			$fname = __METHOD__
	)

DELETE query wrapper.

Parameters

string	$table	Table name
string | array	$conds	Array of conditions. See $conds in IDatabase::select() for the format. Use $conds == "*" to delete all rows
string	$fname	Name of the calling function

Exceptions

DBUnexpectedError

Returns

bool|IResultWrapper

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

Referenced by UserGroupMembership\delete(), DBFileJournal\doPurgeOldLogs(), UserGroupMembership\purgeExpired(), Block\purgeExpired(), Title\purgeExpiredRestrictions(), and QueryPage\recache().

deleteJoin()

Wikimedia\Rdbms\IDatabase::deleteJoin	(		$delTable,
			$joinTable,
			$delVar,
			$joinVar,
			$conds,
			$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.

Parameters

string	$delTable	The table to delete from.
string	$joinTable	The other table.
string	$delVar	The variable to join on, in the first table.
string	$joinVar	The variable to join on, in the second table.
array	$conds	Condition array of field names mapped to variables, ANDed together in the WHERE clause
string	$fname	Calling function name (use METHOD) for logs/profiling

Exceptions

DBUnexpectedError

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

doAtomicSection()

Wikimedia\Rdbms\IDatabase::doAtomicSection	(		$fname,
		callable	$callback
	)

Run a callback to do an atomic set of updates for this database.

The $callback takes the following arguments:

• This database object
• The value of $fname

If any exception occurs in the callback, then rollback() will be called and the error will be re-thrown. It may also be that the rollback itself fails with an exception before then. In any case, such errors are expected to terminate the request, without any outside caller attempting to catch errors and commit anyway. Note that any rollback undoes all prior atomic section and uncommitted updates, which trashes the current request, requiring an error to be displayed.

This can be an alternative to explicit startAtomic()/endAtomic() calls.

See also

Database::startAtomic

Database::endAtomic

Parameters

string	$fname	Caller name (usually METHOD)
callable	$callback	Callback that issues DB updates

Returns

mixed $res Result of the callback (since 1.28)

Exceptions

DBError
RuntimeException
UnexpectedValueException

Since

1.27

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

doneWrites()

Wikimedia\Rdbms\IDatabase::doneWrites

(

)

Returns true if the connection may have been used for write queries.

Should return true if unsure.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

encodeBlob()

Wikimedia\Rdbms\IDatabase::encodeBlob

(

$b

)

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 IDatabase::insert().

Parameters

string

$b

Returns

string|Blob

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseSqlite, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

encodeExpiry()

Wikimedia\Rdbms\IDatabase::encodeExpiry

(

$expiry

)

Encode an expiry time into the DBMS dependent format.

Parameters

string

$expiry

Timestamp for expiry, or the 'infinity' string

Returns

string

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Block\getDatabaseArray().

endAtomic()

Wikimedia\Rdbms\IDatabase::endAtomic

(

$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 also

IDatabase::startAtomic

Parameters

string

$fname

Exceptions

DBError

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by JobQueueDB\doBatchPushInternal().

estimateRowCount()

Wikimedia\Rdbms\IDatabase::estimateRowCount	(		$table,
			$vars = ' *',
			$conds = '',
			$fname = __METHOD__,
			$options = []
	)

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 IDatabase::select().

Parameters

string	$table	Table name
string	$vars	Unused
array | string	$conds	Filters on the table
string	$fname	Function name for profiling
array	$options	Options for select

Returns

int Row count

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DBConnRef.

explicitTrxActive()

Wikimedia\Rdbms\IDatabase::explicitTrxActive

(

)

Returns

bool Whether an explicit transaction or atomic sections are still open

Since

1.28

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\approveMasterChanges(), and DeferredUpdates\areDatabaseTransactionsActive().

fetchObject()

Wikimedia\Rdbms\IDatabase::fetchObject

(

$res

)

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.

Parameters

IResultWrapper | stdClass

$res

Object as returned from IDatabase::query(), etc.

Returns

stdClass|bool

Exceptions

DBUnexpectedError

Thrown if the database returns an error

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMysqlBase, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\Database\selectRow(), and Wikimedia\Rdbms\Database\textFieldSize().

fetchRow()

Wikimedia\Rdbms\IDatabase::fetchRow

(

$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.

Parameters

IResultWrapper

$res

Result object as returned from IDatabase::query(), etc.

Returns

array|bool

Exceptions

DBUnexpectedError

Thrown if the database returns an error

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\Database\estimateRowCount(), Wikimedia\Rdbms\Database\selectField(), and Wikimedia\Rdbms\Database\selectRowCount().

fieldExists()

Wikimedia\Rdbms\IDatabase::fieldExists	(		$table,
			$field,
			$fname = __METHOD__
	)

Determines whether a field exists in a table.

Parameters

string	$table	Table name
string	$field	Filed to check on that table
string	$fname	Calling function name (optional)

Returns

bool Whether $table has filed $field

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

fieldInfo()

Wikimedia\Rdbms\IDatabase::fieldInfo	(		$table,
			$field
	)

mysql_fetch_field() wrapper Returns false if the field doesn't exist

Parameters

string	$table	Table name
string	$field	Field name

Returns

Field

Implemented in Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMssql, DatabaseOracle, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\Database\fieldExists().

fieldName()

Wikimedia\Rdbms\IDatabase::fieldName	(		$res,
			$n
	)

Get a field name in a result object.

See also

https://secure.php.net/mysql_field_name

Parameters

mixed	$res	A SQL result
int	$n

Returns

string

Implemented in DatabaseOracle, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

flushSnapshot()

Wikimedia\Rdbms\IDatabase::flushSnapshot

(

$fname = __METHOD__

)

Commit any transaction but error out if writes or callbacks are pending.

This is intended for clearing out REPEATABLE-READ snapshots so that callers can see a new point-in-time of the database. This is useful when one of many transaction rounds finished and significant time will pass in the script's lifetime. It is also useful to call on a replica DB after waiting on replication to catch up to the master.

Parameters

string

$fname

Calling function name

Exceptions

DBUnexpectedError

Since

1.28

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\commitMasterChanges(), and Wikimedia\Rdbms\LoadBalancer\flushReplicaSnapshots().

freeResult()

Wikimedia\Rdbms\IDatabase::freeResult

(

$res

)

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.

Parameters

mixed

$res

A SQL result

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DBConnRef, and Wikimedia\Rdbms\DatabaseMssql.

getDBname()

Wikimedia\Rdbms\IDatabase::getDBname

(

)

Get the current DB name.

Returns

string

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DBConnRef.

getDomainID()

Wikimedia\Rdbms\IDatabase::getDomainID

(

)

Returns

string

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Revision\newKnownCurrent(), ResourceLoaderWikiModule\preloadTitleInfo(), and Wikimedia\Rdbms\LoadBalancer\setDomainPrefix().

getFlag()

Wikimedia\Rdbms\IDatabase::getFlag

(

$flag

)

Returns a boolean whether the flag $flag is set for this connection.

Parameters

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

Returns

bool

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\applyTransactionRoundFlags(), and Wikimedia\Rdbms\LoadBalancer\undoTransactionRoundFlags().

getInfinity()

Wikimedia\Rdbms\IDatabase::getInfinity

(

)

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.

Returns

string

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

getLag()

Wikimedia\Rdbms\IDatabase::getLag

(

)

Get replica DB 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.

Returns

int|bool Database replication lag in seconds or false on error

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\safeGetLag().

getLBInfo()

Wikimedia\Rdbms\IDatabase::getLBInfo

(

$name = null

)

Get properties passed down from the server info array of the load balancer.

Parameters

string

$name

The entry of the info array to get, or null to get the whole array

Returns

array|mixed|null

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\applyTransactionRoundFlags(), Wikimedia\Rdbms\LoadBalancer\closeConnection(), Wikimedia\Rdbms\LoadBalancer\commitAll(), Wikimedia\Rdbms\LoadBalancer\safeWaitForMasterPos(), Wikimedia\Rdbms\LoadBalancer\setDomainPrefix(), and Wikimedia\Rdbms\LoadBalancer\undoTransactionRoundFlags().

getMasterPos()

Wikimedia\Rdbms\IDatabase::getMasterPos

(

)

Get the position of this master.

Returns

DBMasterPos|bool False if this is not a master

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

getReplicaPos()

Wikimedia\Rdbms\IDatabase::getReplicaPos

(

)

Get the replication position of this replica DB.

Returns

DBMasterPos|bool False if this is not a replica DB.

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

getScopedLockAndFlush()

Wikimedia\Rdbms\IDatabase::getScopedLockAndFlush	(		$lockKey,
			$fname,
			$timeout
	)

Acquire a named lock, flush any transaction, and return an RAII style unlocker object.

Only call this from outer transcation scope and when only one DB will be affected. See https://www.mediawiki.org/wiki/Database_transactions for details.

This is suitiable for transactions that need to be serialized using cooperative locks, where each transaction can see each others' changes. Any transaction is flushed to clear out stale REPEATABLE-READ snapshot data. Once the returned object falls out of PHP scope, the lock will be released unless a transaction is active. If one is active, then the lock will be released when it either commits or rolls back.

If the lock acquisition failed, then no transaction flush happens, and null is returned.

Parameters

string	$lockKey	Name of lock to release
string	$fname	Name of the calling method
int	$timeout	Acquisition timeout in seconds

Returns

ScopedCallback|null

Exceptions

DBUnexpectedError

Since

1.27

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by LinksUpdate\acquirePageLock(), DatabaseTest\badLockingMethodExplicit(), and DatabaseTest\badLockingMethodImplicit().

getServer()

Wikimedia\Rdbms\IDatabase::getServer

(

)

Get the server hostname or IP address.

Returns

string

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\closeAll().

getServerInfo()

Wikimedia\Rdbms\IDatabase::getServerInfo

(

)

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.

Returns

string Version information from the database server

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

getServerUptime()

Wikimedia\Rdbms\IDatabase::getServerUptime

(

)

Determines how long the server has been up.

Returns

int

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

getServerVersion()

Wikimedia\Rdbms\IDatabase::getServerVersion

(

)

A string describing the current software version, like from mysql_get_server_info().

Returns

string Version information from the database server.

Implemented in Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseMssql, DatabaseOracle, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DBConnRef, and FakeDatabaseMysqlBase.

Referenced by Wikimedia\Rdbms\Database\getServerInfo().

getSessionLagStatus()

Wikimedia\Rdbms\IDatabase::getSessionLagStatus

(

)

Get the replica DB lag when the current transaction started or a general lag estimate if not transaction is active.

This is useful when transactions might use snapshot isolation (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data is this lag plus transaction duration. If they don't, it is still safe to be pessimistic. In AUTO-COMMIT mode, this still gives an indication of the staleness of subsequent reads.

Returns

array ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)

Since

1.27

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

getSoftwareLink()

Wikimedia\Rdbms\IDatabase::getSoftwareLink

(

)

Returns a wikitext link to the DB's website, e.g., return "[https://www.mysql.com/ MySQL]"; Should at least contain plain text, if for some reason your database has no website.

Returns

string Wikitext of a link to the server software's web site

Implemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

getType()

Wikimedia\Rdbms\IDatabase::getType

(

)

Get the type of the DBMS, as it appears in $wgDBtype.

Returns

string

Implemented in Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DBConnRef, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, DatabaseOracle, and Wikimedia\Rdbms\DatabasePostgres.

Referenced by SearchEngineFactory\getSearchEngineClass(), DatabaseInstaller\getSqlFilePath(), WatchedItemQueryService\getWatchedItemsWithRCInfoQueryConds(), MediaWikiTestCase\listTables(), DatabaseUpdater\newForDB(), DatabaseUpdater\patchPath(), MediaWikiTestCase\resetDB(), MediaWikiTestCase\setupDatabaseWithTestPrefix(), and MediaWikiTestCase\setupTestDB().

getWikiID()

Wikimedia\Rdbms\IDatabase::getWikiID

(

)

Alias for getDomainID()

Returns

string

Deprecated:

1.30

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

implicitGroupby()

Wikimedia\Rdbms\IDatabase::implicitGroupby

(

)

Returns true if this database does an implicit sort when doing GROUP BY.

Returns

bool

Deprecated:

Since 1.30; only use grouped or aggregated fields in the SELECT

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DBConnRef, DatabaseOracle, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseMssql.

implicitOrderby()

Wikimedia\Rdbms\IDatabase::implicitOrderby

(

)

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.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DBConnRef, DatabaseOracle, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseMssql.

indexExists()

Wikimedia\Rdbms\IDatabase::indexExists	(		$table,
			$index,
			$fname = __METHOD__
	)

Determines whether an index exists Usually throws a DBQueryError on failure If errors are explicitly ignored, returns NULL on failure.

Parameters

string	$table
string	$index
string	$fname

Returns

bool|null

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

indexUnique()

Wikimedia\Rdbms\IDatabase::indexUnique	(		$table,
			$index
	)

Determines if a given index is unique.

Parameters

string	$table
string	$index

Returns

bool

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

insert()

Wikimedia\Rdbms\IDatabase::insert	(		$table,
			$a,
			$fname = __METHOD__,
			$options = []
	)

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 IDatabase::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 IDatabase::affectedRows().

Parameters

string	$table	Table name. This will be passed through Database::tableName().
array	$a	Array of rows to insert
string	$fname	Calling function name (use METHOD) for logs/profiling
array	$options	Array of options

Returns

bool

Implemented in Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseSqlite, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

Referenced by CommentStore\createComment(), UserGroupMembership\delete(), JobQueueDB\doBatchPushInternal(), DBFileJournal\doLogChangeBatch(), UserGroupMembership\insert(), CommentStore\insertInternal(), MigrateComments\loadCommentIDs(), UserGroupMembership\purgeExpired(), and QueryPage\recache().

insertId()

Wikimedia\Rdbms\IDatabase::insertId

(

)

Get the inserted value of an auto-increment row.

This should only be called after an insert that used an auto-incremented value. If no such insert was previously done in the current database session, the return value is undefined.

Returns

int

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DBConnRef, Wikimedia\Rdbms\DatabaseMysqli, Wikimedia\Rdbms\DatabaseMysql, and FakeDatabaseMysqlBase.

Referenced by CommentStore\createComment().

insertSelect()

Wikimedia\Rdbms\IDatabase::insertSelect	(		$destTable,
			$srcTable,
			$varMap,
			$conds,
			$fname = __METHOD__,
			$insertOptions = [],
			$selectOptions = [],
			$selectJoinConds = []
	)

INSERT SELECT wrapper.

Takes data from a SELECT query and inserts it into another table.

Parameters

string	$destTable	The table name to insert into
string | array	$srcTable	May be either a table name, or an array of table names to include in a join.
array	$varMap	Must be an associative array of the form [ 'dest1' => 'source1', ... ]. Source items may be literals rather than field names, but strings should be quoted with IDatabase::addQuotes()
array	$conds	Condition array. See $conds in IDatabase::select() for the details of the format of condition arrays. May be "*" to copy the whole table.
string	$fname	The function name of the caller, from METHOD
array	$insertOptions	Options for the INSERT part of the query, see IDatabase::insert() for details.
array	$selectOptions	Options for the SELECT part of the query, see IDatabase::select() for details.
array	$selectJoinConds	Join conditions for the SELECT part of the query, see IDatabase::select() for details.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

isOpen()

Wikimedia\Rdbms\IDatabase::isOpen

(

)

Is a connection to the database open?

Returns

bool

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\openConnection().

isReadOnly()

Wikimedia\Rdbms\IDatabase::isReadOnly

(

)

Returns

bool Whether this DB is read-only

Since

1.27

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

lastDoneWrites()

Wikimedia\Rdbms\IDatabase::lastDoneWrites

(

)

Returns the last time the connection may have been used for write queries.

Should return a timestamp if unsure.

Returns

int|float UNIX timestamp or false

Since

1.24

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\lastMasterChangeTimestamp().

lastErrno()

Wikimedia\Rdbms\IDatabase::lastErrno

(

)

Get the last error number.

See also

https://secure.php.net/mysql_errno

Returns

int

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, Wikimedia\Rdbms\DBConnRef, Wikimedia\Rdbms\DatabaseMysqli, Wikimedia\Rdbms\DatabaseMysql, and FakeDatabaseMysqlBase.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\fetchObject(), Wikimedia\Rdbms\DatabaseMysqlBase\fetchRow(), Wikimedia\Rdbms\Database\query(), Wikimedia\Rdbms\DatabaseMysqlBase\wasDeadlock(), Wikimedia\Rdbms\DatabaseMysqlBase\wasErrorReissuable(), Wikimedia\Rdbms\DatabaseMysqlBase\wasLockTimeout(), and Wikimedia\Rdbms\DatabaseMysqlBase\wasReadOnlyError().

lastError()

Wikimedia\Rdbms\IDatabase::lastError

(

)

Get a description of the last error.

See also

https://secure.php.net/mysql_error

Returns

string

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

Referenced by MediaWikiTestCase\assertSelect(), Wikimedia\Rdbms\Database\query(), Wikimedia\Rdbms\Database\reportConnectionError(), and Wikimedia\Rdbms\Database\sourceStream().

lastQuery()

Wikimedia\Rdbms\IDatabase::lastQuery

(

)

Return the last query that went through IDatabase::query()

Returns

string

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

listTables()

Wikimedia\Rdbms\IDatabase::listTables	(		$prefix = null,
			$fname = __METHOD__
	)

List all tables on the database.

Parameters

string	$prefix	Only show tables with this prefix, e.g. mw_
string	$fname	Calling function name

Exceptions

DBError

Returns

array

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

lock()

Wikimedia\Rdbms\IDatabase::lock	(		$lockName,
			$method,
			$timeout = 5
	)

Acquire a named lock.

Named locks are not related to transactions

Parameters

string	$lockName	Name of lock to aquire
string	$method	Name of the calling method
int	$timeout	Acquisition timeout in seconds

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

lockIsFree()

Wikimedia\Rdbms\IDatabase::lockIsFree	(		$lockName,
			$method
	)

Check to see if a named lock is available (non-blocking)

Parameters

string	$lockName	Name of lock to poll
string	$method	Name of method calling us

Returns

bool

Since

1.20

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

makeList()

Wikimedia\Rdbms\IDatabase::makeList	(		$a,
			$mode = self::LIST_COMMA
	)

Makes an encoded list of strings from an array.

These can be used to make conjunctions or disjunctions on SQL condition strings derived from an array (see IDatabase::select() $conds documentation).

Example usage:

$sql = $db->makeList( [
    'rev_user' => $id,
    $db->makeList( [ 'rev_minor' => 1, 'rev_len' < 500 ], $db::LIST_OR ] )
], $db::LIST_AND );

This would set $sql to "rev_user = '$id' AND (rev_minor = '1' OR rev_len < '500')"

Parameters

array	$a	Containing the data
int	$mode	IDatabase class constant: IDatabase::LIST_COMMA: Comma separated, no field names IDatabase::LIST_AND: ANDed WHERE clause (without the WHERE). IDatabase::LIST_OR: ORed WHERE clause (without the WHERE) IDatabase::LIST_SET: Comma separated with field names, like a SET clause IDatabase::LIST_NAMES: Comma separated field names

Exceptions

DBError

Returns

string

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by WatchedItemQueryService\getExtraDeletedPageLogEntryRelatedCond(), WatchedItemQueryService\getFromUntilTargetConds(), WatchedItemQueryService\getStartFromConds(), WANCacheReapUpdate\getTitleChangeEvents(), WatchedItemStore\getVisitingWatchersCondition(), WatchedItemQueryService\getWatchedItemsWithRCInfoQueryConds(), and MigrateComments\loadCommentIDs().

makeWhereFrom2d()

Wikimedia\Rdbms\IDatabase::makeWhereFrom2d	(		$data,
			$baseKey,
			$subKey
	)

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.

Parameters

array	$data	Organized as 2-d [ baseKeyVal => [ subKeyVal => [ignored], ... ], ... ]
string	$baseKey	Field name to match the base-level keys to (eg 'pl_namespace')
string	$subKey	Field name to match the sub-level keys to (eg 'pl_title')

Returns

string|bool SQL fragment, or false if no items in array

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

masterPosWait()

Wikimedia\Rdbms\IDatabase::masterPosWait	(	DBMasterPos	$pos,
			$timeout
	)

Wait for the replica DB to catch up to a given master position.

Parameters

DBMasterPos	$pos
int	$timeout	The maximum number of seconds to wait for synchronisation

Returns

int|null Zero if the replica DB was past that position already, greater than zero if we waited for some period of time, less than zero if it timed out, and null on error

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\safeWaitForMasterPos().

maxListLen()

Wikimedia\Rdbms\IDatabase::maxListLen

(

)

Return the maximum number of items allowed in a list, or 0 for unlimited.

Returns

int

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

namedLocksEnqueue()

Wikimedia\Rdbms\IDatabase::namedLocksEnqueue

(

)

Check to see if a named lock used by lock() use blocking queues.

Returns

bool

Since

1.26

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

nextSequenceValue()

Wikimedia\Rdbms\IDatabase::nextSequenceValue

(

$seqName

)

Deprecated method, calls should be removed.

This was formerly used for PostgreSQL and Oracle to handle self::insertId() auto-incrementing fields. It is no longer necessary since DatabasePostgres::insertId() has been reimplemented using lastval() and Oracle has been reimplemented using triggers.

Implementations should return null if inserting NULL into an auto-incrementing field works, otherwise it should return an instance of NextSequenceValue and filter it on calls to relevant methods.

Deprecated:

since 1.30, no longer needed

Parameters

string

$seqName

Returns

null|NextSequenceValue

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DBConnRef.

numFields()

Wikimedia\Rdbms\IDatabase::numFields

(

$res

)

Get the number of fields in a result object.

See also

https://secure.php.net/mysql_num_fields

Parameters

mixed

$res

A SQL result

Returns

int

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

numRows()

Wikimedia\Rdbms\IDatabase::numRows

(

$res

)

Get the number of rows in a result object.

Parameters

mixed

$res

A SQL result

Returns

int

Implemented in Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\Database\selectField(), and Wikimedia\Rdbms\Database\selectRow().

onTransactionIdle()

Wikimedia\Rdbms\IDatabase::onTransactionIdle	(	callable	$callback,
			$fname = __METHOD__
	)

Run a callback 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.

Updates will execute in the order they were enqueued.

The callback takes one argument:

• How the transaction ended (IDatabase::TRIGGER_COMMIT or IDatabase::TRIGGER_IDLE)

Parameters

callable	$callback
string	$fname	Caller name

Since

1.20

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by PurgeJobUtils\invalidatePages().

onTransactionPreCommitOrIdle()

Wikimedia\Rdbms\IDatabase::onTransactionPreCommitOrIdle	(	callable	$callback,
			$fname = __METHOD__
	)

Run a callback 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. If no transaction is active, then a transaction will wrap the callback.

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.

Updates will execute in the order they were enqueued.

Parameters

callable	$callback
string	$fname	Caller name

Since

1.22

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

onTransactionResolution()

Wikimedia\Rdbms\IDatabase::onTransactionResolution	(	callable	$callback,
			$fname = __METHOD__
	)

Run a callback as soon as the current transaction commits or rolls back.

An error is thrown if no transaction is pending. 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 combining cooperative locks and DB transactions.

The callback takes one argument:

• How the transaction ended (IDatabase::TRIGGER_COMMIT or IDatabase::TRIGGER_ROLLBACK)

Parameters

callable	$callback
string	$fname	Caller name

Returns

mixed

Since

1.28

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

open()

Wikimedia\Rdbms\IDatabase::open	(		$server,
			$user,
			$password,
			$dbName
	)

Open a connection to the database.

Usually aborts on failure

Parameters

string	$server	Database server host
string	$user	Database user name
string	$password	Database user password
string	$dbName	Database name

Returns

bool

Exceptions

DBConnectionError

Implemented in Wikimedia\Rdbms\DBConnRef, Wikimedia\Rdbms\DatabaseMysqlBase, DatabaseOracle, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DatabaseSqlite.

Referenced by Wikimedia\Rdbms\Database\__clone(), Wikimedia\Rdbms\Database\__construct(), and Wikimedia\Rdbms\Database\reconnect().

pendingWriteCallers()

Wikimedia\Rdbms\IDatabase::pendingWriteCallers

(

)

Get the list of method names that did write queries for this transaction.

Returns

array

Since

1.27

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\pendingMasterChangeCallers().

pendingWriteQueryDuration()

Wikimedia\Rdbms\IDatabase::pendingWriteQueryDuration

(

$type = self::ESTIMATE_TOTAL

)

Get the time spend running write queries for this transaction.

High times could be due to scanning, updates, locking, and such

Parameters

string

$type

IDatabase::ESTIMATE_* constant [default: ESTIMATE_ALL]

Returns

float|bool Returns false if not transaction is active

Since

1.26

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\approveMasterChanges().

pendingWriteRowsAffected()

Wikimedia\Rdbms\IDatabase::pendingWriteRowsAffected

(

)

Get the number of affected rows from pending write queries.

Returns

int

Since

1.30

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

ping()

Wikimedia\Rdbms\IDatabase::ping

(

&

$rtt = null

)

Ping the server and try to reconnect if it there is no connection.

Parameters

float | null

&$rtt

Value to store the estimated RTT [optional]

Returns

bool Success or failure

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\approveMasterChanges(), and Wikimedia\Rdbms\LoadBalancer\pingAll().

query()

Wikimedia\Rdbms\IDatabase::query	(		$sql,
			$fname = __METHOD__,
			$tempIgnore = false
	)

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.

Parameters

string	$sql	SQL query
string	$fname	Name of the calling function, for profiling/SHOW PROCESSLIST comment (you can use METHOD or add some extra info)
bool	$tempIgnore	Whether to avoid throwing an exception on errors... maybe best to catch the exception instead?

Exceptions

DBError

Returns

bool|IResultWrapper True for a successful write query, IResultWrapper object for a successful read query, or false on failure if $tempIgnore set

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DBConnRef, and DatabaseSqliteMock.

Referenced by DatabaseTest\badLockingMethodImplicit(), MySqlLockManager\initConnection(), and MwSql\sqlDoQuery().

replace()

Wikimedia\Rdbms\IDatabase::replace	(		$table,
			$uniqueIndexes,
			$rows,
			$fname = __METHOD__
	)

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.

Parameters

string	$table	The table to replace the row(s) in.
array	$uniqueIndexes	Is an array of indexes. Each element may be either a field name or an array of field names
array	$rows	Can be either a single row to insert, or multiple rows, in the same format as for IDatabase::insert()
string	$fname	Calling function name (use METHOD) for logs/profiling

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

reportConnectionError()

Wikimedia\Rdbms\IDatabase::reportConnectionError

(

$error = 'Unknown error'

)

Parameters

string

$error

Fallback error message, used if none is given by DB

Exceptions

DBConnectionError

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

reportQueryError()

Wikimedia\Rdbms\IDatabase::reportQueryError	(		$error,
			$errno,
			$sql,
			$fname,
			$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.

Parameters

string	$error
int	$errno
string	$sql
string	$fname
bool	$tempIgnore

Exceptions

DBQueryError

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DBConnRef.

restoreFlags()

Wikimedia\Rdbms\IDatabase::restoreFlags

(

$state = self::RESTORE_PRIOR

)

Restore the flags to their prior state before the last setFlag/clearFlag call.

Parameters

string

$state

IDatabase::RESTORE_* constant. [default: RESTORE_PRIOR]

Since

1.28

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\undoTransactionRoundFlags().

rollback()

Wikimedia\Rdbms\IDatabase::rollback	(		$fname = __METHOD__,
			$flush = ''
	)

Rollback a transaction previously started using begin().

If no transaction is in progress, a warning is issued.

Only call this from code with outer transcation scope. See https://www.mediawiki.org/wiki/Database_transactions for details. Nesting of transactions is not supported. If a serious unexpected error occurs, throwing an Exception is preferrable, using a pre-installed error handler to trigger rollback (in any case, failure to issue COMMIT will cause rollback server-side).

Parameters

string	$fname	Calling function name
string	$flush	Flush flag, set to a situationally valid IDatabase::FLUSHING_* constant 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.

Exceptions

DBUnexpectedError

Since

1.23 Added $flush parameter

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\rollbackMasterChanges(), and Maintenance\rollbackTransaction().

select()

Wikimedia\Rdbms\IDatabase::select	(		$table,
			$vars,
			$conds = '',
			$fname = __METHOD__,
			$options = [],
			$join_conds = []
	)

Execute a SELECT query constructed using the various parameters provided.

See below for full details of the parameters.

Parameters

string | array	$table	Table name
string | array	$vars	Field names
string | array	$conds	Conditions
string	$fname	Caller function name
array	$options	Query options
array	$join_conds	Join conditions
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:

[ '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 Database::tableName(), which causes the table prefix (if any) to be added, and various other table name mappings to be performed.

Do not use untrusted user input as a table name. Alias names should not have characters outside of the Basic multilingual plane.

Parameters

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:

[ '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.

Untrusted user input must not be passed to this parameter.

Parameters

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:

• IDatabase::buildLike()
• IDatabase::conditional()

Untrusted user input is safe in the values of string keys, however untrusted input must not be used in the array key names or in the values of numeric keys. Escaping of untrusted input used in values of numeric keys should be done via IDatabase::addQuotes()

Parameters

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:

[ '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 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

Parameters

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 the same as the $conds parameter. Thus it can be an SQL fragment, or an array where the string keys are equality and the numeric keys are SQL fragments all AND'd together. For example:

[ 'page' => [ 'LEFT JOIN', 'page_latest=rev_id' ] ]

Returns

IResultWrapper|bool If the query returned no rows, a IResultWrapper 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.

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

Referenced by JobQueueDB\doBatchPushInternal(), DBFileJournal\doGetChangeEntries(), RefreshImageMetadata\execute(), ResourceLoaderWikiModule\fetchTitleInfo(), WANCacheReapUpdate\getTitleChangeEvents(), MigrateComments\loadCommentIDs(), PopulateContentModel\populatePage(), PopulateContentModel\populateRevisionOrArchive(), and UserGroupMembership\purgeExpired().

selectDB()

Wikimedia\Rdbms\IDatabase::selectDB

(

$db

)

Change the current database.

Parameters

string

$db

Returns

bool Success or failure

Exceptions

DBConnectionError

If databasesAreIndependent() is true and an error occurs

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMssql, DatabaseOracle, Wikimedia\Rdbms\DBConnRef, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DatabaseMysqli, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseMysql.

selectField()

Wikimedia\Rdbms\IDatabase::selectField	(		$table,
			$var,
			$cond = '',
			$fname = __METHOD__,
			$options = [],
			$join_conds = []
	)

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.

Parameters

string | array	$table	Table name. See IDatabase::select() for details.
string	$var	The field name to select. This must be a valid SQL fragment: do not use unvalidated user input.
string | array	$cond	The condition array. See IDatabase::select() for details.
string	$fname	The function name of the caller.
string | array	$options	The query options. See IDatabase::select() for details.
string | array	$join_conds	The query join conditions. See IDatabase::select() for details.

Returns

bool|mixed The value from the field, or false on failure.

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by CommentStore\createComment(), DBFileJournal\doGetCurrentPosition(), DBFileJournal\doGetPositionAtTime(), and LocalFileMoveBatch\verifyDBUpdates().

selectFieldValues()

Wikimedia\Rdbms\IDatabase::selectFieldValues	(		$table,
			$var,
			$cond = '',
			$fname = __METHOD__,
			$options = [],
			$join_conds = []
	)

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.

Parameters

string | array	$table	Table name. See IDatabase::select() for details.
string	$var	The field name to select. This must be a valid SQL fragment: do not use unvalidated user input.
string | array	$cond	The condition array. See IDatabase::select() for details.
string	$fname	The function name of the caller.
string | array	$options	The query options. See IDatabase::select() for details.
string | array	$join_conds	The query join conditions. See IDatabase::select() for details.

Returns

bool|array The values from the field, or false on failure

Since

1.25

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by PurgeJobUtils\invalidatePages(), and Title\purgeExpiredRestrictions().

selectRow()

Wikimedia\Rdbms\IDatabase::selectRow	(		$table,
			$vars,
			$conds,
			$fname = __METHOD__,
			$options = [],
			$join_conds = []
	)

Single row SELECT wrapper.

Equivalent to IDatabase::select(), except that a single row object is returned. If the query returns no rows, false is returned.

Parameters

string | array	$table	Table name
string | array	$vars	Field names
array	$conds	Conditions
string	$fname	Caller function name
string | array	$options	Query options
array | string	$join_conds	Join conditions

Returns

stdClass|bool

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

Referenced by LinkCache\fetchPageRow(), and UserGroupMembership\insert().

selectRowCount()

Wikimedia\Rdbms\IDatabase::selectRowCount	(		$tables,
			$vars = ' *',
			$conds = '',
			$fname = __METHOD__,
			$options = [],
			$join_conds = []
	)

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 IDatabase::select().

Since

1.27 Added $join_conds parameter

Parameters

array | string	$tables	Table names
string	$vars	Unused
array | string	$conds	Filters on the table
string	$fname	Function name for profiling
array	$options	Options for select
array	$join_conds	Join conditions (since 1.27)

Returns

int Row count

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

selectSQLText()

Wikimedia\Rdbms\IDatabase::selectSQLText	(		$table,
			$vars,
			$conds = '',
			$fname = __METHOD__,
			$options = [],
			$join_conds = []
	)

The equivalent of IDatabase::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().

Parameters

string | array	$table	Table name
string | array	$vars	Field names
string | array	$conds	Conditions
string	$fname	Caller function name
string | array	$options	Query options
string | array	$join_conds	Join conditions

Returns

string SQL query string.

See also

IDatabase::select()

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

serverIsReadOnly()

Wikimedia\Rdbms\IDatabase::serverIsReadOnly

(

)

Returns

bool Whether the DB is marked as read-only server-side

Since

1.28

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

setBigSelects()

Wikimedia\Rdbms\IDatabase::setBigSelects

(

$value = true

)

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.

Parameters

bool | string

$value

True for allow, false for deny, or "default" to restore the initial value

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

setFlag()

Wikimedia\Rdbms\IDatabase::setFlag	(		$flag,
			$remember = self::REMEMBER_NOTHING
	)

Set a flag for this connection.

Parameters

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
string	$remember	IDatabase::REMEMBER_* constant [default: REMEMBER_NOTHING]

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\applyTransactionRoundFlags().

setLazyMasterHandle()

Wikimedia\Rdbms\IDatabase::setLazyMasterHandle

(

IDatabase

$conn

)

Set a lazy-connecting DB handle to the master DB (for replication status purposes)

Parameters

IDatabase

$conn

Since

1.27

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

setLBInfo()

Wikimedia\Rdbms\IDatabase::setLBInfo	(		$name,
			$value = 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.

Parameters

string	$name
array	$value

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

setSchemaVars()

Wikimedia\Rdbms\IDatabase::setSchemaVars

(

$vars

)

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.

Parameters

bool | array

$vars

Mapping variable name to value.

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

setSessionOptions()

Wikimedia\Rdbms\IDatabase::setSessionOptions

(

array

$options

)

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.

Parameters

array

$options

Returns

void

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

setTableAliases()

Wikimedia\Rdbms\IDatabase::setTableAliases

(

array

$aliases

)

Make certain table names use their own database, schema, and table prefix when passed into SQL queries pre-escaped and without a qualified database name.

For example, "user" can be converted to "myschema.mydbname.user" for convenience. Appearances like user, somedb.user, somedb.someschema.user will used literally.

Calling this twice will completely clear any old table aliases. Also, note that callers are responsible for making sure the schemas and databases actually exist.

Parameters

array[]

$aliases

Map of (table => (dbname, schema, prefix) map)

Since

1.28

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

setTransactionListener()

Wikimedia\Rdbms\IDatabase::setTransactionListener	(		$name,
		callable	$callback = null
	)

Run a callback each time any transaction commits or rolls back.

The callback takes two arguments:

• IDatabase::TRIGGER_COMMIT or IDatabase::TRIGGER_ROLLBACK
• This IDatabase object Callbacks must commit any transactions that they begin.

Registering a callback here will not affect writesOrCallbacks() pending

Parameters

string	$name	Callback name
callable | null	$callback	Use null to unset a listener

Returns

mixed

Since

1.28

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\setTransactionListener().

startAtomic()

Wikimedia\Rdbms\IDatabase::startAtomic

(

$fname = __METHOD__

)

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.

All atomic levels must be explicitly closed using IDatabase::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

Parameters

string

$fname

Exceptions

DBError

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by JobQueueDB\doBatchPushInternal(), and MySqlLockManager\initConnection().

strreplace()

Wikimedia\Rdbms\IDatabase::strreplace	(		$orig,
			$old,
			$new
	)

Returns a command for str_replace function in SQL query.

Uses REPLACE() in MySQL

Parameters

string	$orig	Column to modify
string	$old	Column to seek
string	$new	Column to replace with

Returns

string

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

tableExists()

Wikimedia\Rdbms\IDatabase::tableExists	(		$table,
			$fname = __METHOD__
	)

Query whether a given table exists.

Parameters

string	$table
string	$fname

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMssql, DatabaseOracle, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

tablePrefix()

Wikimedia\Rdbms\IDatabase::tablePrefix

(

$prefix = null

)

Get/set the table prefix.

Parameters

string

$prefix

The table prefix to set, or omitted to leave it unchanged.

Returns

string The previous table prefix.

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\setDomainPrefix().

timestamp()

Wikimedia\Rdbms\IDatabase::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.

The result is unquoted, and needs to be passed through addQuotes() before it can be included in raw SQL.

Parameters

string | int

$ts

Returns

string

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

Referenced by DBFileJournal\doGetPositionAtTime(), DBFileJournal\doLogChangeBatch(), DBFileJournal\doPurgeOldLogs(), UserGroupMembership\getDatabaseArray(), Block\getDatabaseArray(), WatchedItemQueryService\getStartEndConds(), WatchedItemQueryService\getStartFromConds(), WANCacheReapUpdate\getTitleChangeEvents(), WatchedItemStore\getVisitingWatchersCondition(), UserGroupMembership\insert(), Title\invalidateCache(), PurgeJobUtils\invalidatePages(), UserGroupMembership\purgeExpired(), Block\purgeExpired(), Title\purgeExpiredRestrictions(), and QueryPage\recache().

timestampOrNull()

Wikimedia\Rdbms\IDatabase::timestampOrNull

(

$ts = null

)

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.

Parameters

string | int

$ts

Returns

string

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

trxLevel()

Wikimedia\Rdbms\IDatabase::trxLevel

(

)

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.

Returns

int The previous value

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

trxTimestamp()

Wikimedia\Rdbms\IDatabase::trxTimestamp

(

)

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.

Returns

float|null Returns null if there is not active transaction

Since

1.25

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

unionConditionPermutations()

Wikimedia\Rdbms\IDatabase::unionConditionPermutations	(		$table,
			$vars,
		array	$permute_conds,
			$extra_conds = '',
			$fname = __METHOD__,
			$options = [],
			$join_conds = []
	)

Construct a UNION query for permutations of conditions.

Databases sometimes have trouble with queries that have multiple values for multiple condition parameters combined with limits and ordering. This method constructs queries for the Cartesian product of the conditions and unions them all together.

See also

IDatabase::select()

Since

1.30

Parameters

string | array	$table	Table name
string | array	$vars	Field names
array	$permute_conds	Conditions for the Cartesian product. Keys are field names, values are arrays of the possible values for that field.
string | array	$extra_conds	Additional conditions to include in the query.
string	$fname	Caller function name
string | array	$options	Query options. In addition to the options recognized by IDatabase::select(), the following may be used: NOTALL: Set to use UNION instead of UNION ALL. INNER ORDER BY: If specified and supported, subqueries will use this instead of ORDER BY.
string | array	$join_conds	Join conditions

Returns

string SQL query string.

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

unionQueries()

Wikimedia\Rdbms\IDatabase::unionQueries	(		$sqls,
			$all
	)

Construct a UNION query This is used for providing overload point for other DB abstractions not compatible with the MySQL syntax.

Parameters

array	$sqls	SQL statements to combine
bool	$all	Use UNION ALL

Returns

string SQL fragment

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

unionSupportsOrderAndLimit()

Wikimedia\Rdbms\IDatabase::unionSupportsOrderAndLimit

(

)

Returns true if current database backend supports ORDER BY or LIMIT for separate subqueries within the UNION construct.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseSqlite, Wikimedia\Rdbms\DBConnRef, and Wikimedia\Rdbms\DatabaseMssql.

unlock()

Wikimedia\Rdbms\IDatabase::unlock	(		$lockName,
			$method
	)

Release a lock.

Named locks are not related to transactions

Parameters

string	$lockName	Name of lock to release
string	$method	Name of the calling method

Returns

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

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

update()

Wikimedia\Rdbms\IDatabase::update	(		$table,
			$values,
			$conds,
			$fname = __METHOD__,
			$options = []
	)

UPDATE wrapper.

Takes a condition array and a SET array.

Parameters

string	$table	Name of the table to UPDATE. This will be passed through Database::tableName().
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 IDatabase::addQuotes(). Values with integer keys form unquoted SET statements, which can be used for things like "field = field + 1" or similar computed values.
array	$conds	An array of conditions (WHERE). See IDatabase::select() for the details of the format of condition arrays. Use '*' to update all rows.
string	$fname	The function name of the caller (from METHOD), for logging and profiling.
array	$options	An array of UPDATE options, can be: IGNORE: Ignore unique key conflicts LOW_PRIORITY: MySQL-specific, see MySQL manual.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, DatabaseOracle, Wikimedia\Rdbms\DatabaseMssql, and Wikimedia\Rdbms\DBConnRef.

Referenced by LocalFileMoveBatch\doDBUpdates(), UserGroupMembership\insert(), Title\invalidateCache(), PurgeJobUtils\invalidatePages(), PopulateContentModel\updatePageRows(), and PopulateContentModel\updateRevisionOrArchiveRows().

upsert()

Wikimedia\Rdbms\IDatabase::upsert	(		$table,
		array	$rows,
		array	$uniqueIndexes,
		array	$set,
			$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

Parameters

string	$table	Table name. This will be passed through Database::tableName().
array	$rows	A single row or list of rows to insert
array	$uniqueIndexes	List of single field names or field name tuples
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 IDatabase::addQuotes(). Values with integer keys form unquoted SET statements, which can be used for things like "field = field + 1" or similar computed values.
string	$fname	Calling function name (use METHOD) for logs/profiling

Exceptions

Exception

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, DatabaseOracle, and Wikimedia\Rdbms\DBConnRef.

wasDeadlock()

Wikimedia\Rdbms\IDatabase::wasDeadlock

(

)

Determines if the last failure was due to a deadlock.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, DatabaseOracle, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

wasErrorReissuable()

Wikimedia\Rdbms\IDatabase::wasErrorReissuable

(

)

Determines if the last query error was due to a dropped connection and should be dealt with by pinging the connection and reissuing the query.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

wasLockTimeout()

Wikimedia\Rdbms\IDatabase::wasLockTimeout

(

)

Determines if the last failure was due to a lock timeout.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DBConnRef.

wasReadOnlyError()

Wikimedia\Rdbms\IDatabase::wasReadOnlyError

(

)

Determines if the last failure was due to the database being read-only.

Returns

bool

Implemented in Wikimedia\Rdbms\Database, Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabaseSqlite, and Wikimedia\Rdbms\DBConnRef.

writesOrCallbacksPending()

Wikimedia\Rdbms\IDatabase::writesOrCallbacksPending

(

)

Returns true if there is a transaction open with possible write queries or transaction pre-commit/idle callbacks waiting on it to finish.

This does not count recurring callbacks, e.g. from setTransactionListener().

Returns

bool

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

Referenced by Wikimedia\Rdbms\LoadBalancer\approveMasterChanges(), DeferredUpdates\areDatabaseTransactionsActive(), Wikimedia\Rdbms\LoadBalancer\commitMasterChanges(), Wikimedia\Rdbms\LoadBalancer\hasMasterChanges(), and Wikimedia\Rdbms\LoadBalancer\rollbackMasterChanges().

writesPending()

Wikimedia\Rdbms\IDatabase::writesPending

(

)

Returns

bool Whether there is a transaction open with possible write queries

Since

1.27

Implemented in Wikimedia\Rdbms\Database, and Wikimedia\Rdbms\DBConnRef.

---

The documentation for this interface was generated from the following file:

• includes/libs/rdbms/database/IDatabase.php