Marco De Benedetto wrote:
>
> Oracle 7.2.3 on AIX
> I had very very bad performance on a (simple) query
> I don't even know if it would have ended since it took
> too much time and I had to stop it (ctrl+C)
>
> After the export/drop/import of one of table involved
> there were no change,
>
> The solution has been to
> . create table new as select * from old
> . drop old
> . rename new to old
>
> does anybody knows if it is a known bug and what can
> cause such a thing?
>
> thanx
>
> -debe
I think I have found the problem: the day before I analyzed
(estimatete statistic) most, not all, tables so I guess that
Oracle was trying to analyze tables not yet analyzed in join
with other analyze because of the cost based optimizer.
Now a question: how could I 'de'-analyze all tables?
thanks
Received on Thu Oct 28 1999 - 17:22:28 CDT
