On Tue, 11 Jan 2022 at 16:22, Robert Haas <robertmh...@gmail.com> wrote:
> This is just a relatively simple example and I think there are > probably a bunch of others. There are a lot of kinds of DDL that could > be performed on a partition that gets pruned away: DROP INDEX is just > one example. I haven't followed this in any detail, but this patch and its goal of reducing the O(N) drag effect on partition execution time is very important. Locking a long list of objects that then get pruned is very wasteful, as the results show. Ideally, we want an O(1) algorithm for single partition access and DDL is rare. So perhaps that is the starting point for a safe design - invent a single lock or cache that allows us to check if the partition hierarchy has changed in any way, and if so, replan, if not, skip locks. Please excuse me if this idea falls short, if so, please just note my comment about how important this is. Thanks. -- Simon Riggs http://www.EnterpriseDB.com/
