Adam Mackler <AdamMackler@gmail.com> writes:
> WITH RECURSIVE
> tab(id_key,link) AS ( VALUES (1,17), (2,17), (3,17), (4,17), (6,17), (5,17) ),
> iter (id_key, row_type, link) AS (
> SELECT 0, 'base', 17
> UNION(
> WITH remaining(id_key, row_type, link, min) AS (
> SELECT tab.id_key, 'true'::text, iter.link, MIN(tab.id_key) OVER ()
> FROM tab INNER JOIN iter USING (link)
> WHERE tab.id_key > iter.id_key
> ),
> first_remaining AS (
> SELECT id_key, row_type, link
> FROM remaining
> WHERE id_key=min
> ),
> effect AS (
> SELECT tab.id_key, 'new'::text, tab.link
> FROM first_remaining e INNER JOIN tab ON e.id_key=tab.id_key
> /* Try changing this WHERE clause to other false expressions */
> WHERE e.row_type='false'
> )
> SELECT * FROM first_remaining
> /* Try uncommenting the next line */
> --UNION SELECT * FROM effect
> )
> )
> SELECT DISTINCT * FROM iter
Right offhand I'm inclined to think that the reference to "iter"
inside the first sub-WITH ought to be disallowed. I don't recall
the exact rules about where a recursive reference can appear, but
it sure doesn't seem like that ought to be OK, does it?
regards, tom lane
