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Re: seqscan instead of index scan

From: Martin Sarsale <martin(at)emepe3(dot)net>
To: Merlin Moncure <merlin(dot)moncure(at)rcsonline(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: seqscan instead of index scan
Date: 2004-08-31 15:14:37
Message-ID: 1093965277.1680.93.camel@kadaif (view raw or flat)
Thread:
Lists: pgsql-performance
> Using a functional index you can define an index around the way you
> access the data.  There is no faster or better way to do it...this is a
> mathematical truth, not a problem with the planner.  Why not use the
> right tool for the job?  A boolean index is super-efficient both in disk
> space and cache utilization.

Thanks for your constructive criticism, you're absolutely right.

I had to modify your "return" for a "select":

create function rankeable (bigint, bigint) returns boolean as '
        select case when $1 > 0 or $2 > 0 then true else false end;'
language sql immutable;

and it works great.


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