On Mon, Apr 23, 2018 at 8:46 PM, Alvaro Herrera <alvhe...@alvh.no-ip.org> wrote: > Hello Amit > > Amit Langote wrote: > >> acquire_inherited_sample_rows() currently uses equalTupleDescs() being >> false as the condition for going to tupconv.c to determine whether tuple >> conversion is needed. But equalTupleDescs() will always return false if >> it's passed TupleDesc's of two different tables, which is the most common >> case here. So I first thought we should just unconditionally go to >> tupconv.c, but there is still one case where we don't need to, which is >> the case where the child table is same as the parent table. However, it >> would be much cheaper to just check if the relation OIDs are different >> instead of calling equalTupleDescs, which the attached patch teaches it to >> do. > > When (not if) we get around to updating equalTupleDescs to cope, we will > need this call right where it is (and we'd have a hard time finding this > potential callsite later, I think). If this were a hot spot I would be > happy to change it, but it's not so I'd rather leave it alone. > +1
-- Best Wishes, Ashutosh Bapat EnterpriseDB Corporation The Postgres Database Company
