Re: counterintuitive behaviour in pl/pgsql

Hello

yes, this behave is strange, and should be fixed

Regards

Pavel Stehule

2011/5/21 Dan S <strd911(at)gmail(dot)com>:
> Hi !
>
> I'm running "PostgreSQL 9.0.2, compiled by Visual C++ build 1500, 32-bit"
>
> I have found an odd behaviour in pl/pgsql when using 'return query execute'
> The function produce the dynamic query 'select * from tbl1 where col1 < 4'
> and executes it.
> I would have expected to have 3 rows back with the values 1,2,3 or maybe
> 3,3,3 but it returns all rows in the table ??
> Here is a self contained test case that shows the behaviour.
> And yes I do know that I can fix the problem by renaming the output column
> to something else than i , I'm just curious about the behaviour and if it
> should work like this and why.
>
> create table tbl1 ( col1 int, constraint pk_tb1 primary key (col1));
>
> insert into tbl1 values (1),(2),(3),(4),(5),(6);
>
> CREATE OR REPLACE FUNCTION dynamic_query(i int) RETURNS TABLE (i int) as $$
> DECLARE
>     stmt text;
>     cond text;
> BEGIN
>     stmt := 'select * from tbl1 ';
>
>     IF (i IS NOT NULL) THEN cond := ' col1 < $1 '; END IF;
>     IF (cond IS NOT NULL) THEN stmt := stmt || 'where ' || cond; END IF;
>     RETURN QUERY EXECUTE stmt USING i;
> RETURN;
> END;
> $$ language plpgsql;
>
> select * from dynamic_query(4);
>
>
> Best Regards
> Dan S
>