Has anyone offered any answers to you? No one else has replied to this post.
"Ow Mun Heng" <Ow.Mun.Heng@xxxxxxx> wrote in message
news:1190616376.17050.51.camel@xxxxxxxxxxxxxxxxxxxxxxx
On Thu, 2007-09-20 at 11:02 -0400, Carlo Stonebanks wrote:
(SORRY FOR THE REPOST, I DON'T SEE MY ORIGINAL QUESTION OR ANY ANSWERS
HERE)
I am noticing that my queries are spending a lot of time in nested loops.
The table/index row estimates are not bad, but the nested loops can be
off
by a factor of 50. In any case, they are always too high.
Are the over-estimations below significant, and if so, is this an
indication
of a general configuration problem?
Sounds much like the issue I was seeing as well.
Unique (cost=67605.91..67653.18 rows=4727 width=16) (actual
time=8634.618..8637.918 rows=907 loops=1)
You can to rewrite the queries to individual queries to see it if helps.
In my case, I was doing
select a.a,b.b,c.c from
(select a from x where) a <--- Put as a SRF
left join (
select b from y where ) b <--- Put as a SRF
on a.a = b.a
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