Re: PL/pgSQL PERFORM with CTE

On 2013-08-20 14:15:55 +0200, David E. Wheeler wrote:
> Hi Pavel,
>
> On Aug 20, 2013, at 2:11 PM, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> wrote:
>
> >> david=# DO $$
> >> david$# BEGIN
> >> david$# WITH now AS (SELECT now())
> >> david$# PERFORM * from now;
> >> david$# END;
> >> david$# $$;
> >> ERROR: syntax error at or near "PERFORM"
> >> LINE 4: PERFORM * from now;
> >> ^
> >> Parser bug in PL/pgSQL, perhaps?
> >
> > no
> >
> > you cannot use a PL/pgSQL statement inside SQL statement.
>
> Well, there ought to be *some* way to tell PL/pgSQL to discard the result. Right now I am adding a variable to select into but never otherwise use. Inelegant, IMHO. Perhaps I’m missing some other way to do it?
>
> If so, it would help if the hint suggesting the use of PERFORM pointed to such alternatives.

Not that that's elegant but IIRC PERFORM (WITH ...) ought to work. I
don't think the intermingled plpgsql/sql grammars allow a nice way right
now.

Greetings,

Andres Freund

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