Date: Thu, 25 Mar 2010 07:16:17 +0100
From: Louis-David Mitterrand <vindex+lists-pgsql-sql@apartia.org>
To: pgsql-sql@postgresql.org
Subject: Re: Does IMMUTABLE property propagate?
Message-ID: <20100325061616.GA4629@apartia.fr>
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On Sat, Mar 06, 2010 at 04:31:55PM -0500, Tom Lane wrote:
> Petru Ghita <petrutz@venaver.info> writes:
> > "..immediately replaced with the function value" doesn't mean that the
> > results of a previously evaluated function for the same parameters are
> > stored and reused?
> 
> No, it means what it says: the function is executed once and replaced
> with a constant representing the result value.

So for example a function like:


	CREATE OR REPLACE FUNCTION shorten_cruise_type(intext text) RETURNS text
		AS $$
	declare
		outtext text;
	begin
		outtext = trim(regexp_replace(intext, E'\\s*Short( Break)?', '', 'i'));
		return outtext;
	end;
	$$
		LANGUAGE plpgsql;

could/should be declared immutable?

Thanks,