Re: BUG #6067: In PL/pgsql, EXISTS(SELECT ... INTO...) fails

On Tue, Nov 29, 2011 at 9:32 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> Tom Lane wrote:
>> "David Fetter" <dfetter(at)vmware(dot)com> writes:
>> >     IF EXISTS (SELECT 1 INTO STRICT i) THEN
>> >         RAISE NOTICE '%', a;
>> >     END IF;
>>
>> Umm ... are you just complaining that the error message isn't very
>> helpful, or are you actually expecting that to do something useful?
>> If the latter, what exactly?  I'm particularly confused by your use
>> of the STRICT option here, because if we did support that, I would
>> expect the STRICT to throw an error if there were not exactly one
>> matching row, making the EXISTS test 100% pointless.
>>
>> But the short answer is that we don't support INTO in sub-selects,
>> and in general I doubt that we ever will, since in most cases the
>> behavior wouldn't be very well-defined.  It might be worth a TODO
>> to provide a better error message than "syntax error", though.
>
> Is it worth documenting, fixing, or adding this to the TODO list?

At most I would say we could try to improve the error message.

--
Robert Haas
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