Re: polymorphic arguments and return type for PL/pgSQL

From: Joe Conway <mail(at)joeconway(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Patches (PostgreSQL)" <pgsql-patches(at)postgresql(dot)org>
Subject: Re: polymorphic arguments and return type for PL/pgSQL
Date: 2003-06-30 18:40:47
Message-ID: 3F00842F.4010508@joeconway.com
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Tom Lane wrote:
> The latter. By the time you pay the price of a hash lookup, a slightly
> longer key is nearly free. (Maybe entirely free, since it might produce
> better-distributed hash values.)

OK -- I figured that's what you'd say, so I've already started down that
road.

> dynahash only supports fixed-length keys, so don't forget to zero out
> unused positions in the argument type vector.

Important safety tip! Thanks.

> BTW, I can't see any need to include the return type in the hash key ---
> wouldn't it be predetermined given the argument types?

Yup, very true.

Thanks,

Joe

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