On 29/1/26 06:04, Alexandra Wang wrote:
Hi hackers,
As promised in my previous email, I'm sharing a proof-of-concept patch
exploring join statistics for correlated columns across relations.
This is a POC at this point, but I hope the performance numbers below
give a better idea of both the potential usefulness of join statistics
and the complexity of implementing them.
I wonder why you chose the JOIN operator only?
It seems to me that any relational operator produces relational output
that can be treated as a table. The extended statistics code may be
adopted to such relations.
I think it may be a VIEW that you can declare (manually or
automatically) and allow Postgres to build statistics on this 'virtual'
table. So, the main focus may shift to the question: how to provably
match a query subtree to a specific statistic.
--
regards, Andrei Lepikhov,
pgEdge
