From: | Chris Field <cfields(at)affinitysolutions(dot)com> |
---|---|
To: | Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> |
Cc: | Doug McNaught <doug(at)wireboard(dot)com>, Postgresql <pgsql-hackers(at)postgresql(dot)org> |
Subject: | Re: Upgrading to 7.2 |
Date: | 2002-02-14 17:33:55 |
Message-ID: | 1013708037.1605.20.camel@tux.dogoodsoft.org |
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Lists: | pgsql-hackers |
On Thu, 2002-02-14 at 12:31, Bruce Momjian wrote:
> Chris Field wrote:
>
> Checking application/pgp-signature: FAILURE
> -- Start of PGP signed section.
> > Thanks for responding, I am thinking it might be fairly beneficial to
> > upgrade.
> >
> > > Ummm, max() is an aggregate function, how can you create an index on
> > > it?
> >
> > In the postgresSQL Essential Reference by Barry Stinson it specifically
> > has a index topic on functional indexes, with the given example being
> > " CREATE INDEX max_payroll_idx ON payroll (MAX(salary)); "
> > so either the book was a waste of money, or this is a 7.2 specific
> > feature.
>
> Uh, MAX() is an aggregate, not really a function like the other
> functions. It takes an entire column and returns one value, rather than
> normal functions that take a some values and return a single value.
>
> In summary, I don't think we support aggregates (MAX) in functional
> indexes.
>
So, to put it succinctly book=wrong;
--
Chris Field
Affinity Solutions Inc.
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