From: Dave Dutcher <dave@tridecap.com>
To: 'Mario Splivalo' <msplival@jagor.srce.hr>
To: pgsql-performance@postgresql.org
Subject: Re: Lot'sa joins - performance tip-up, please?
Date: Wed, 3 May 2006 10:20:35 -0500
Message-ID: <003001c66ec5$205a0160$8300a8c0@tridecap.com> (raw)
In-Reply-To: <1146533274.14006.11.camel@localhost.localdomain>
> -> Nested Loop (cost=0.00..176144.30 rows=57925 width=26)
> (actual time=68.322..529472.026 rows=57925 loops=1)
> -> Seq Scan on ticketing_codes_played
> (cost=0.00..863.25 rows=57925 width=8) (actual time=0.042..473.881
> rows=57925 loops=1)
> -> Index Scan using ticketing_codes_pk on
> ticketing_codes (cost=0.00..3.01 rows=1 width=18) (actual
> time=9.102..9.108 rows=1 loops=57925)
> Index Cond: (ticketing_codes.code_id =
> "outer".code_id)
> Total runtime: 542000.093 ms
> (27 rows)
>
>
> I'll be more than happy to provide any additional information
> that I may
> be able to gather. I'd be most happy if someone would scream something
> like "four joins, smells like a poor design" because design
> is poor, but
> the system is in production, and I have to bare with it.
It looks like that nested loop which is joining ticketing_codes_played
to ticketing_codes is the slow part. I'm curious how many rows are in
the ticketing_codes table?
Four or five joins does not seem like a lot to me, but it can be slow if
you are joining big tables with other big tables.
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To: pgsql-performance@postgresql.org
Cc: dave@tridecap.com, msplival@jagor.srce.hr
Subject: Re: Lot'sa joins - performance tip-up, please?
In-Reply-To: <003001c66ec5$205a0160$8300a8c0@tridecap.com>
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