Re: [HACKERS] Partition-wise join for join between (declaratively)partitioned tables
От | Ashutosh Bapat |
---|---|
Тема | Re: [HACKERS] Partition-wise join for join between (declaratively)partitioned tables |
Дата | |
Msg-id | CAFjFpRdEXxtRd0y_7E6wM9x2mJkxuMQQXz4dFmUUomjn9tCyMg@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: [HACKERS] Partition-wise join for join between (declaratively)partitioned tables (Robert Haas <robertmhaas@gmail.com>) |
Список | pgsql-hackers |
> >> I don't think we will get away by supporting just scan paths, since >> the inner side of lateral join can be any paths not just scan path. Or >> you are suggesting that we disable partition-wise lateral join and >> support reparameterization of only scan paths? > > I think if you can do a straight-up partitionwise nested loop between > two tables A and B, that's pretty bad. Ok. > But if there are more complex > cases that involve parameterizing entire join trees which aren't > covered, that's less bad. Parallel query almost entirely punts on > LATERAL right now, and nobody's complained yet. I'm sure that'll need > to get fixed someday, but not today. > Ok. I am suggesting this possibility in case we run of time to review and commit reparameterize_path_by_child() entirely. If we can do that, I will be happy. In case, we have to include a stripped down version of reparameterize_path_by_child(), with which I am fine too, we will need to disable LATERAL joins, so that we don't end up with an error "could not devise a query plan for the given query". -- Best Wishes, Ashutosh Bapat EnterpriseDB Corporation The Postgres Database Company
В списке pgsql-hackers по дате отправления: