From: William Yu <wyu@talisys.com>
To: pgsql-performance@postgresql.org
Subject: Re: Forcing use of specific index
Date: Fri, 03 Jun 2005 16:22:49 -0700
Message-ID: <d7qooc$4pf$1@news.hub.org> (raw)
In-Reply-To: <20050602020528.GL26100@tobias.exoweb.net>
References: <20050602020528.GL26100@tobias.exoweb.net>
A pretty awful way is to mangle the sql statement so the other field
logical statements are like so:
select * from mytable where 0+field = 100
Tobias Brox wrote:
> Is it any way to attempt to force the planner to use some specific index
> while creating the plan? Other than eventually dropping all the other
> indices (which is obiously not a solution in production setting anyway)?
>
> I have one case where I have added 16 indices to a table, many of them
> beeing partial indices. The table itself has only 50k of rows, but are
> frequently used in heavy joins. I imagine there can be exponential order on
> the number of alternative paths the planner must examinate as function of
> the number of indices?
>
> It seems to me that the planner is quite often not choosing the "best"
> index, so I wonder if there is any easy way for me to check out what the
> planner think about a specific index :-)
>
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To: pgsql-performance@postgresql.org
Cc: wyu@talisys.com
Subject: Re: Forcing use of specific index
In-Reply-To: <d7qooc$4pf$1@news.hub.org>
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