Re: string_to_array has to be stable?

On Thu, Jul 29, 2010 at 1:10 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Thu, Jul 29, 2010 at 1:00 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> Or we could decide that volatile domain CHECK expressions are un-sensible
>>> and just relabel all these input functions as stable, which would make
>>> everything consistent.  Thoughts?
>
>> Aren't volatile CHECK expressions pretty un-sensible in general?
>
> Yeah, probably so.  I can't think of a use-case that seems like it would
> justify the possible performance hit from having to assume all functions
> performing datatype input calls are volatile.

That's my thought, too.  Any non-immutable CHECK constraint is
basically playing with fire, to some degree.  But a stable check
constraint is at least playing with it somewhat responsibly, whereas a
volatile check constraint strikes me as more like doing it while
bathing in turpentine.

--
Robert Haas
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