pá 9. 10. 2020 v 11:40 odesílatel Peter Eisentraut < peter.eisentr...@2ndquadrant.com> napsal:
> On 2020-09-22 20:29, Pavel Stehule wrote: > > The result is correct. When I tried to use UNION instead UNION ALL, the > > pg crash > > I fixed the crash, but UNION [DISTINCT] won't actually work here because > row/record types are not hashable. I'm leaving the partial support in, > but I'm documenting it as currently not supported. > I think so UNION is a common solution against the cycles. So missing support for this specific case is not a nice thing. How much work is needed for hashing rows. It should not be too much code. > > looks so clause USING in cycle detection is unsupported for DB2 and > > Oracle - the examples from these databases doesn't work on PG without > > modifications > > Yeah, the path clause is actually not necessary from a user's > perspective, but it's required for internal bookkeeping. We could > perhaps come up with a mechanism to make it invisible coming out of the > CTE (maybe give the CTE a target list internally), but that seems like a > separate project. > > The attached patch fixes the issues you have reported (also the view > issue from the other email). I have also moved the whole rewrite > support to a new file to not blow up rewriteHandler.c so much. > > -- > Peter Eisentraut http://www.2ndQuadrant.com/ > PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services >