Re: PL/pgSQL PERFORM with CTE - Mailing list pgsql-hackers

From Pavel Stehule
Subject Re: PL/pgSQL PERFORM with CTE
Date
Msg-id CAFj8pRDmd3JDdJ8MtL_E7JbBnFn8KYA=Ykee9JJoEhoN932JEw@mail.gmail.com
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In response to Re: PL/pgSQL PERFORM with CTE  ("David E. Wheeler" <david@justatheory.com>)
Responses Re: PL/pgSQL PERFORM with CTE  (Marko Tiikkaja <marko@joh.to>)
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2013/8/20 David E. Wheeler <david@justatheory.com>
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 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.

postgres=# DO $$              
 BEGIN
   PERFORM * FROM (WITH now AS (SELECT now())
  SELECT * from now) x;
 END;
$$;
DO
postgres=#

Regards

Pavel
 

Best,

David


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