Reply-To: <nickf@ontko.com>
From: "Nick Fankhauser" <nickf@ontko.com>
To: <wweng@kencast.com>, <pgsql-sql@postgresql.org>
Subject: Re: create index on function - why?
Date: Fri, 15 Feb 2002 11:33:41 -0500
Message-ID: <NEBBLAAHGLEEPCGOBHDGIELJEFAA.nickf@ontko.com>
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I don't know yet if it will help me. (I was doing empirical research when I
ran into my problem.) My reasoning went like this:

Since using a function in my "where" clause forces postgresql to do a table
scan instead of using my index on the field, I was hoping to build an index
on the function, which *would* get used. I'm pretty sure this will work, but
I'll post my results to the list if I find that it doesn't work.

-Nick


> -----Original Message-----
> From: pgsql-sql-owner@postgresql.org
> [mailto:pgsql-sql-owner@postgresql.org]On Behalf Of Wei Weng
> Sent: Friday, February 15, 2002 11:26 AM
> To: pgsql-sql@postgresql.org
> Subject: [SQL] create index on function - why?
>
>
> I can understand the rationale behind creating index on tables, it
> speeds up the searching.
>
> But what is the rationale behind creating index on a function? how does
> it help with the database performance?
>
> Thank you.
>
> --
> Wei Weng
> Network Software Engineer
> KenCast Inc.
>
>
>
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