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.stehule@gmail.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
intobut 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

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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