Re: Seq scan on zero-parameters function

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Richard Huxton <dev(at)archonet(dot)com>
Cc: alvarezp(at)alvarezp(dot)ods(dot)org, pgsql-performance(at)postgresql(dot)org
Subject: Re: Seq scan on zero-parameters function
Date: 2004-02-06 14:55:28
Message-ID: 29560.1076079328@sss.pgh.pa.us
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Richard Huxton <dev(at)archonet(dot)com> writes:
> It's not entirely clear to me why this form is different from the other form
> though.

The code that checks for expressions containing unstable functions
doesn't look inside sub-selects. Arguably this is a bug, but people
were relying on that behavior way back before we had these nice
STABLE/IMMUTABLE tags for functions. I'm hesitant to change it for
fear of breaking people's apps.

regards, tom lane

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