Re: massive performance hit when using "Limit 1"

From: Rich Doughty <rich(at)opusvl(dot)com>
To: Rich Doughty <rich(at)opusvl(dot)com>, pgsql-general(at)postgresql(dot)org
Subject: Re: massive performance hit when using "Limit 1"
Date: 2005-12-06 10:08:58
Message-ID: 4395633A.5040507@opusvl.com
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Rich Doughty wrote:
> can anyone explain the reason for the difference in the
> following 2 query plans, or offer any advice? the two queries
> are identical apart from the limit clause.

[snip]

fwiw, join order makes no difference here either. i get a slightly
different plan, but with LIMIT 1 postgres make a really strange
planner choice.

As before LIMIT > 1 the choice is logical and performance fine.

- Rich Doughty

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