Db2 performance issue



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Db2 performance issue

Postby tambe vaishali » Sun Oct 26, 2008 12:28 am

Hi,
some SQL queries taking lot of time.Actually it's a cursor.. which contains select from joining of 2-3 tables and not existalso..
basic form in is::
select count(*) ,... from table1 a table2 b,table3 c
where a.--=b.-- and b.--=c.-- etc
and not exist
(select d, e, f from table d,table e
where ..)

Basically table also contain around 600000 rows.
Please suggest any option to tune this query to reduce time
tambe vaishali
 
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Re: Db2 performance issue

Postby dick scherrer » Sun Oct 26, 2008 12:39 am

Hello and welcome to the forum,

Actually it's a cursor..
I susperct the cursor is incidental - the query looks awful (if performance is a concern). . .

Please suggest any option to tune this query to reduce time
Suggest you look for a different approach and not try for the "single query" solution. You might have found a way to save yourself a bit of code, but you may have also found a way to put the machine to sleep.
Hope this helps,
d.sch.
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