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From: ryan groth <postgres@cpusoftware.com>
To: ryan groth <postgres@cpusoftware.com>
To: Steinar H. Gunderson <sgunderson@bigfoot.com>
To: pgsql-performance@postgresql.org
Subject: Re: Joins and full index scans...mysql vs postgres?
Date: Wed, 22 Feb 2006 13:21:04 -0500
Message-ID: <E1FBybo-0005wh-Vn@zeus.liquidweb.com> (raw)


workmem is set to the default, increasing it decreases performance.

> Does this work:
> 
> "Merge Left Join  (cost=0.00..2656.36 rows=6528 width=1522) (actual
> time=0.057..123.659 rows=6528 loops=1)"
> "  Merge Cond: ("outer".uid = "inner".uid)"
> "  ->  Merge Left Join  (cost=0.00..1693.09 rows=6528 width=1264)
> (actual time=0.030..58.876 rows=6528 loops=1)"
> "        Merge Cond: ("outer".uid = "inner".user_id)"
> "        ->  Index Scan using users_pkey on users  (cost=0.00..763.81
> rows=6528 width=100) (actual time=0.016..9.446 rows=6528 loops=1)"
> "        ->  Index Scan using phorum_users_base_pkey on
> phorum_users_base  (cost=0.00..822.92 rows=9902 width=1168) (actual
> time=0.007..15.674 rows=9845 loops=1)"
> "  ->  Index Scan using useraux_pkey on useraux  (cost=0.00..846.40
> rows=7582 width=262) (actual time=0.007..11.935 rows=7529 loops=1)"
> "Total runtime: 127.442 ms"
> 
> 
> > On Wed, Feb 22, 2006 at 12:26:47PM -0500, ryan groth wrote:
> > > Postgres Explain 
> > 
> > We need to see EXPLAIN ANALYZE results here.
> > 
> > What's your work_mem set to?
> > 
> > /* Steinar */
> > -- 
> > Homepage: http://www.sesse.net/
> > 
> > ---------------------------(end of broadcast)---------------------------
> > TIP 3: Have you checked our extensive FAQ?
> > 
> >                http://www.postgresql.org/docs/faq
> > 
> > 
> 
> -- 
> 
> 
> > On Wed, Feb 22, 2006 at 12:26:47PM -0500, ryan groth wrote:
> > > Postgres Explain 
> > 
> > We need to see EXPLAIN ANALYZE results here.
> > 
> > What's your work_mem set to?
> > 
> > /* Steinar */
> > -- 
> > Homepage: http://www.sesse.net/
> > 
> > ---------------------------(end of broadcast)---------------------------
> > TIP 3: Have you checked our extensive FAQ?
> > 
> >                http://www.postgresql.org/docs/faq
> > 
> > 
> 
> -- 
> 
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Have you searched our list archives?
> 
>                http://archives.postgresql.org
> 
> 

-- 




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  Subject: Re: Joins and full index scans...mysql vs postgres?
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