On Sat, Jan 23, 2010 at 10:48 PM, KaiGai Kohei <kai...@kaigai.gr.jp> wrote: > (2010/01/24 12:29), Robert Haas wrote: >> I don't think this is ready for committer, becauseTom previously >> objected to the approach taken by this patch here, and no one has >> answered his objections: >> >> http://archives.postgresql.org/pgsql-hackers/2010-01/msg00144.php >> >> I think someone needs to figure out what the worst-case scenario for >> this is performance-wise and submit a reproducible test case with >> benchmark results. In the meantime, I'm going to set this to Waiting >> on Author. > > Basically, I don't think it is not a performance focused command, > because we may be able to assume ALTER TABLE RENAME TO is not much > frequent operations.
I agree - the requirements here are much looser than for, say, SELECT or UPDATE. But it still has to not suck. I think the problem case here might be something like this... create ten tables A1 through A10. Now create 10 more tables B1 through B10 each of which inherits from all of A1 through A10. Now create 10 more tables C1 through C10 that inherit from B1 through B10. Now create 1000 tables D1 through D1000 that inherit from C1 through C10. Now drop a column from A1. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
