V6.0.33 bug on indexed retrievals??
Date: Thu, 7 Apr 1994 15:57:29 +0000
Message-ID: <765734249snz_at_rustle.demon.co.uk>
Has anyone out there come across this "feature" under ORACLE V6.0.33 ??
Symptom: Indexed queries of a large table suddenly take 10 times as
long as usual.
Investigations: VALIDATE INDEX performed - Index validated, no performance
improvement.
Index dropped/recreated - no performance improvement.
Index dropped, data exported, table dropped/recreated, data
imported, index recreated - Performance returns to expected
speed
Each retrieval attempt was performed twice, once with the
TRACE option switched on. In all cases the EXPLAIN PLAN
indicated that it was an indexed retrieval.
Conclusion: The index appears to become unusable, but the Dictionary
and the VALIDATE INDEX options are unable to recognise
this. The fact that dropping/recreating the index does not
clear the problem is confusing.
This is not a common problem, (it has ocurred twice in 18 months), but the ORACLE Help desk assures me they have not had any other occurrences reported to them before (or since?)
- Has anyone got any ideas????
Cheers,
Martin.
Received on Thu Apr 07 1994 - 17:57:29 CEST