Re: Slow performance/response
- From: Stephane Faroult <sfaroult@xxxxxxxxxxxx>
- To: oracle-l@xxxxxxxxxxxxx
- Date: Tue, 29 Jun 2004 22:28:08 +0200
My feeling is that your query should be split into two or three queries.
Parameters passed to handle different cases usually end up in a huge
succession of ORs (like here with :full_time), often resulting in full
scans when in some cases some extremely valid indexes were here for the
taking. Forgive me for not analysing the query in depth, but I have
spotted at least three occurrences of student_analytical (let me guess
... Around 10 million rows?). So many auto-joins with in-line views
which rely heavily on analytical functions look a bit strange to me and
I smell a misuse of those functions. There is an auto-join (somewhere in
the middle :)) which could probably be get ridden of.
I think that you could rewrite this query to better effect in a
shorter time than 3 executions ...
HTH
SF
Leroy Kemnitz wrote:
>The query is:
>
>
>
>
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