This parameter controls the behavior of cursor stability
(CS) scans.
- Configuration type
- Database
- Parameter type
- Configurable
- Configurable by member in a DB2® pureScale® environment
- Default [range]
- ON [ON, AVAILABLE, DISABLED]
For new databases, the default is set to ON. When the default is set to ON your
query will return the currently committed value of the data at the
time when your query is submitted.
During database
upgrade from V9.5 or earlier, the cur_commit configuration
parameter is set to DISABLED to maintain the same
behavior as in previous releases. If you want to use currently committed
on cursor stability scans, you need to set the cur_commit configuration parameter to ON after the upgrade.
You can explicitly set the cur_commit configuration
parameter to AVAILABLE. Once you set this parameter,
you need to explicitly request for currently committed behavior to
see the results that are currently committed.
Note: Three registry
variables DB2_EVALUNCOMMITTED, DB2_SKIPDELETED, and DB2_SKIPINSERTED are affected by currently
committed when cursor stability isolation level is used. These registry
variables are ignored when USE CURRENTLY COMMITTED or WAIT FOR OUTCOME are specified explicitly
on the BIND or at statement prepare time.
Note: Performance considerations
may be applicable in a database where there are significant lock conflicts
when using currently committed. The committed version of the row is
retrieved from the log, and will perform better and avoid log disk
activity when the log record is still in the log buffer. Therefore,
to improve the performance of retrieving previously committed data,
you might consider an increase to the value of the logbufsz parameter.