I’ve been looking at the enhanced commit processing in Oracle 10g Release 2:
Commit Enhancements in Oracle 10g Database Release 2
In writing this article I’ve noticed a discrepancy in the default values for the COMMIT WRITE command and the COMMIT_WRITE parameter.
The COMMIT documentation says:
“If you specify neither
WAITnorNOWAIT, thenWAITis the default. If you specify neitherIMMEDIATEnorBATCH, thenIMMEDIATEis the default.”
In contrast the COMMIT_WRITE documentation says:
“If only
IMMEDIATEorBATCHis specified, but notWAITorNOWAIT, thenWAITmode is assumed.
If onlyWAITorNOWAITis specified, but notIMMEDIATEorBATCH, thenBATCHmode is assumed.”
Is this difference true, or a documentation error? I guess I’ll have to raise a TAR about this, but if anyone knows the answer already I’d be grateful if you could pass it on.
Cheers
Tim…
Update:
The COMMIT_WRITE documentation is incorrect and Oracle support are raising a bug (4668213) against it. When neither BATCH or IMMEDIATE are specified the default action is IMMEDIATE, the same as the COMMIT WRITE command. A metalink note (336219.1) is due to be released soon with the correct information.
Hi Tim,
sorry I cannot help you with your question, but I would like to ask a question on the original article (unfortunately there is no feedback link).
Why is there such a huge timing difference between using the write clause on the one hand, and using alter session on the other hand.
Are the measured times correct?
Thank You.
Björn
Hi.
Each page has a comments link at the bottom. I guess it’s easy to miss 🙂
Regarding the timings, that’s a bad cut & paste on my part. The timings I listed were from a run with 10000 iterations, rather than 1000. I’ve corrected that now. Thanks for the heads-up 🙂
Cheers
Tim…