Обсуждение: Error with returning SETOF Record

A E <cooljoint@yahoo.com> writes:
> CREATE FUNCTION tester(varchar) RETURNS SETOF record as'
> DECLARE
> ft record;
> begin
>       FOR ft IN SELECT * FROM visaapplicants LOOP
>           RETURN NEXT ft;
>       END LOOP;
> return null;
> end;'
>   LANGUAGE 'plpgsql' VOLATILE;
> <calling query>
> select * from tester('a') as (c varchar);
> <exact error>
> ERROR:  wrong record type supplied in RETURN NEXT
> CONTEXT:  PL/pgSQL function "tester" line 6 at return next

That's pretty much what I'd expect, unless table visaapplicants contains
only a single varchar column.  The example works fine for me if I define
visaapplicants that way.
        regards, tom lane

A E wrote:
> I guess the question I have then is how do I return data from a
> select statement using the record datatype? This is only a test
> function I was trying to get info from, but my application is based
> on passing the table name to the function dynamically. How do I do
> this? The documentation is sketchy when it comes to the record
> datatype.

You need to specify in your query the column definition that will 
actually be returned. Here's a simple example:

create table t1 (f1 int, f2 text);
insert into t1 values (1,'a');
insert into t1 values (2,'b');
create table t2 (f1 int, f2 float8);
insert into t2 values (3, 3.14);
insert into t2 values (4, 2.8);

create or replace function getrec(text) returns setof record as '
DECLARE  ft record;
begin  FOR ft IN EXECUTE ''SELECT * FROM '' || $1  LOOP      RETURN NEXT ft;  END LOOP;  return;
end;
' LANGUAGE 'plpgsql' VOLATILE;

regression=# SELECT * FROM getrec('t1') AS (f1 int, f2 text); f1 | f2
----+----  1 | a  2 | b
(2 rows)

regression=# SELECT * FROM getrec('t2') AS (f1 int, f2 float8); f1 |  f2
----+------  3 | 3.14  4 |  2.8
(2 rows)

HTH,

Joe

On Sat, 27 Dec 2003, A E wrote:

> Hi,
>  
> I was wondering if a solution was ever found to the error: "wrong record type supplied in RETURN NEXT" when executing
afunction that returns the Record datatype? I have seen a couple of previous post from Tom Lane and others, but no real
resolution.
>  
> I am attempting to execute this code and I get that error:
>  
> <code>
> CREATE FUNCTION tester(varchar) RETURNS SETOF record as'
> DECLARE
> ft record;
> begin
>       FOR ft IN SELECT * FROM visaapplicants LOOP
>           RETURN NEXT ft;
>       END LOOP;
> return null;

You have to write only return!


> end;'
>   LANGUAGE 'plpgsql' VOLATILE;
>  
Regards Pavel