Re: oracle can ignore hints
- From: Daniel Fink <Daniel.Fink@xxxxxxx>
- To: oracle-l@xxxxxxxxxxxxx
- Date: Fri, 12 Mar 2004 14:35:32 -0700
If you are using a hint to address a performance problem with a query, you
are probably dealing with the symptom. Use the hint as a temporary solution
and try to identify the actual reason for the performance problem. For
example, I used a hint to force an index lookup in a query where I was
doing a "select * from tableA" as an index access path was quicker than a
full table scan. The real problem was that tableA had a HWM set very high
and over 90% of the blocks were empty. That is my real problem, not the
query. By hinting the query, I 'fixed' it, but if I stopped there, all
other queries doing FTS with tableA would suffer from the same performance
problems that would be resolved by rebuilding the table.
Daniel Fink
----------------------------------------------------------------
Please see the official ORACLE-L FAQ: http://www.orafaq.com
----------------------------------------------------------------
To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
put 'unsubscribe' in the subject line.
--
Archives are at //www.freelists.org/archives/oracle-l/
FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
-----------------------------------------------------------------
Other related posts:
