On 11/2/24 01:18, Nikita Malakhov wrote:
> I've corrected failing test and created a patch at Commitfest:
> https://commitfest.postgresql.org/51/5361/ <https://
> commitfest.postgresql.org/51/5361/>
I have played around with this feature, which looks promising for such a
tiny change. It provides a 'bottom boundary' recommendation for
appending subpaths, participating in the 'fractional branch' of paths.
As I see it works consistently with the plans, created for plain tables
filled with similar data.
According to the proposal to change SeqScan logic, IMO, Andy is right.
But it is a separate improvement because it wouldn't work in the case of
LIMIT 10 or 100, as the newly added regression tests demonstrate.
I think this feature gives sensible profit for partitionwise paths.
Pushing this knowledge into subpaths could help postgres_fdw to reduce
network traffic.
--
regards, Andrei Lepikhov