From: Adrian Klaver <aklaver@comcast.net>
To: pgsql-sql@postgresql.org,
 peterw@borstad.com
Subject: Re: FUNCTION problem
Date: Wed, 1 Apr 2009 16:55:58 -0700
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On Wednesday 01 April 2009 4:31:20 pm Peter Willis wrote:
> Hello,
>
> I am having a problem with a FUNCTION.
> The function creates just fine with no errors.
>
> However, when I call the function postgres produces an error.
>
> Perhaps someone can enlighten me.
>
>
> --I can reproduce the error by making a test function
> --that is much easier to follow that the original:
>
> CREATE OR REPLACE FUNCTION test_function(integer)
>    RETURNS SETOF RECORD AS
> $BODY$
>    DECLARE croid integer;
>    BEGIN
>
> 	--PERFORM A SMALL CALCULATION
> 	--DOESNT SEEM TO MATTER WHAT IT IS
>
> 	SELECT INTO croid 2;
>
> 	--A SELECT STATEMENT OUTPUTS RECORDS (one in this case)
> 	SELECT croid,$1;
>    END;
>
> $BODY$
>    LANGUAGE 'plpgsql' VOLATILE
>
>
>
>
> --The call looks like the following:
>
> SELECT test_function(1);
>
>
>
>
>
> --The resulting error reads as follows:
>
> ERROR:  query has no destination for result data
> HINT:  If you want to discard the results of a SELECT, use PERFORM instead.
> CONTEXT:  PL/pgSQL function "test_function" line 5 at SQL statement
>
> ********** Error **********
>
> ERROR: query has no destination for result data
> SQL state: 42601
> Hint: If you want to discard the results of a SELECT, use PERFORM instead.
> Context: PL/pgSQL function "test_function" line 5 at SQL statement

You have declared function to RETURN SETOF. In order for that to work you need 
to do RETURN NEXT. See below for difference between RETURN and RETURN NEXT:
http://www.postgresql.org/docs/8.3/interactive/plpgsql-control-structures.html#PLPGSQL-CONTROL-STRUCTURES-LOOPS


-- 
Adrian Klaver
aklaver@comcast.net