Date: Mon, 2 Oct 2017 13:46:42 -0500
From: Nico Williams <nico@cryptonector.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Adam Brusselback <adambrusselback@gmail.com>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: generated columns
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On Mon, Oct 02, 2017 at 02:30:38PM -0400, Tom Lane wrote:
> Nico Williams <nico@cryptonector.com> writes:
> > On Mon, Oct 02, 2017 at 12:50:14PM -0400, Adam Brusselback wrote:
> >> So for me, i'd rather default to compute on read, as long storing the
> >> pre-computed value is an option when necessary.
> 
> > Sure, I agree.  I was just wondering whether there might be any other
> > difference besides performance characteristics.  The answer to that is,
> > I think, "no".
> 
> What about non-immutable functions in the generation expression?

Aha, thanks!  Yes, that would be noticeable.

Nico
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