ttCkpt
The ttCkpt
built-in procedure enables you to manually perform fuzzy or nonblocking checkpoints.
Fuzzy checkpoints, or non-blocking checkpoints, allow transactions to run against the database while the checkpoint is in progress. A nonblocking checkpoint does not require any locks on the database. See Checkpoint Operations in Oracle TimesTen In-Memory Database Operations Guide to learn more about checkpoints.
By default, TimesTen automatically performs background checkpoints at regular intervals. Usually, you can set the automatic checkpoint mechanism with the CkptFrequency
and CkptLogVolume
connection attributes, but you can also manually initiate a checkpoint operation by calling the ttCkpt
procedure. Also, TimesTen recommends that you perform regular backups using the ttBackup
utility to minimize the risk of potential data loss.
A backup always contains a checkpoint file; therefore, backing up and checkpointing operations can conflict. Regardless of whether the checkpoint is a background checkpoint or an application-requested checkpoint, the following scenarios are possible:
-
If a backup or checkpoint is running and you try to do a backup, it waits for the running backup or checkpoint to finish.
-
If a checkpoint is currently running and you attempt a checkpoint, the following error returns:
TT625: Checkpoint cannot proceed because the following conflicting operation is in progress: Checkpoint started by connection id id (pid pid; name 'db-name')
-
If a backup is currently running and you attempt a checkpoint, the following error returns:
TT625: Checkpoint cannot proceed because the following conflicting operation is in progress: Backup started by connection id id (pid pid; name 'db-name')
When a database crashes and the checkpoints on disk are nonblocking checkpoints, TimesTen uses both the checkpoint files and the log to recover.
Required Privilege
This procedure requires the ADMIN
privilege.
Usage in TimesTen Scaleout and TimesTen Classic
This procedure is supported in TimesTen Classic but not supported in TimesTen Scaleout.
Related Views
This procedure has no related views.
Syntax
ttCkpt()
Parameters
ttCkpt
has no parameters.
Result Set
ttCkpt
returns no results.
Examples
CALL ttCkpt();
See Also