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 might 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.