CHECKPOINT (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

Generates a manual checkpoint in the SQL Server database to which you are currently connected.

Transact-SQL syntax conventions

Syntax

CHECKPOINT [ checkpoint_duration ]  

Arguments

checkpoint_duration
Specifies the requested amount of time, in seconds, for the manual checkpoint to complete. When checkpoint_duration is specified, the SQL Server Database Engine attempts to perform the checkpoint within the requested duration. The checkpoint_duration must be an expression of type int and must be greater than zero. When this parameter is omitted, the Database Engine adjusts the checkpoint duration to minimize the performance impact on database applications. checkpoint_duration is an advanced option.

Factors Affecting the Duration of Checkpoint Operations

In general, the amount time required for a checkpoint operation increases with the number of dirty pages that the operation must write. By default, to minimize the performance impact on other applications, SQL Server adjusts the frequency of writes that a checkpoint operation performs. Decreasing the write frequency increases the time the checkpoint operation requires to complete. SQL Server uses this strategy for a manual checkpoint unless a checkpoint_duration value is specified in the CHECKPOINT command.

The performance impact of using checkpoint_duration depends on the number of dirty pages, the activity on the system, and the actual duration specified. For example, if the checkpoint would normally complete in 120 seconds, specifying a checkpoint_duration of 45 seconds causes SQL Server to devote more resources to the checkpoint than would be assigned by default. In contrast, specifying a checkpoint_duration of 180 seconds would cause SQL Server to assign fewer resources than would be assigned by default. In general, a short checkpoint_duration will increase the resources devoted to the checkpoint, while a long checkpoint_duration will reduce the resources devoted to the checkpoint. SQL Server always completes a checkpoint if possible, and the CHECKPOINT statement returns immediately when a checkpoint completes. Therefore, in some cases, a checkpoint may complete sooner than the specified duration or may run longer than the specified duration.

Security

Permissions

CHECKPOINT permissions default to members of the sysadmin fixed server role and the db_owner and db_backupoperator fixed database roles, and are not transferable.

See Also

ALTER DATABASE (Transact-SQL)
Database Checkpoints (SQL Server)
Configure the recovery interval Server Configuration Option
SHUTDOWN (Transact-SQL)