Re: Unexpected results when using GROUP BY GROUPING SETS and bind variables

Aner Perez <aner.perez+pgsql-general@gmail.com> writes:
> Or if using indexed path elements in the GROUP BY is the issue and I should
> put the array indexing in a subselect and do the aggregation in the outer
> select.  Like this:

> -- Safer Subselect Version --
> SELECT level1, level2, level3, level4, sum(value)
> FROM (
>     SELECT path[1] as level1, path[2] as level2, path[3] as level3, path[4]
> as level4, value
>     FROM bind_group_by
> ) AS expanded
> GROUP BY GROUPING SETS (
>     (level1, level2, level3, level4),
>     (level1, level2, level3),
>     (level1, level2),
>     (level1),
>     ()
> )
> ORDER BY 1, 2, 3, 4;

Yeah, that one looks a lot safer from here.  There's no question about
which expressions are supposed to match what.  It should end up with
the same plan, too.

            regards, tom lane