Database connection manager. More...

Inherits Wikimedia\Rdbms\ConnectionManager.

Collaboration diagram for Wikimedia\Rdbms\SessionConsistentConnectionManager:

Public Member Functions
	getReadConnection (?array $groups=null, int $flags=0)

	getWriteConnection (int $flags=0)

	prepareForUpdates ()
	Forces all future calls to getReadConnection() to return a write connection.

Public Member Functions inherited from Wikimedia\Rdbms\ConnectionManager
	__construct (ILoadBalancer $loadBalancer, $domain=false, array $groups=[])

Detailed Description

Database connection manager.

This manages access to primary and replica databases. It also manages state that indicates whether the replica databases are possibly outdated after a write operation, and thus the primary database should be used for subsequent read operations.

Note: : Services that access overlapping sets of database tables, or interact with logically related sets of data in the database, should share a SessionConsistentConnectionManager. Services accessing unrelated sets of information may prefer to not share a SessionConsistentConnectionManager, so they can still perform read operations against replica databases after a (unrelated, per the assumption) write operation to the primary database. Generally, sharing a SessionConsistentConnectionManager improves consistency (by avoiding race conditions due to replication lag), but can reduce performance (by directing more read operations to the primary database server).