Gregory Stark <stark(at)enterprisedb(dot)com> writes:
> The following query causes an assertion failure on CVS head:
> SELECT * FROM (SELECT 1 AS i) AS a WHERE NOT EXISTS (SELECT 1 WHERE 1 <> i);
Fixed, thanks for the report.
> Looks like it's assuming there's at least one relation on each side of the
> join.
Yeah. I don't think we can remove that assumption easily; best to just
not try to optimize this case.
regards, tom lane