Robert Haas <robertmh...@gmail.com> writes: > On Mon, Dec 27, 2010 at 6:42 AM, Simon Riggs <si...@2ndquadrant.com> wrote: >> Idea is to reduce lock level of ADD/DROP COLUMN from AccessExclusiveLock >> down to ShareRowExclusiveLock. >> >> To make it work, we need to recognise that we are adding a column >> without rewriting the table.
> Can you elaborate on why you think that's the right test? It seems to > me there could be code out there that assumes that the tuple > descriptor won't change under it while it holds an AccessShareLock. s/could/definitely is/ I think this is guaranteed to break stuff; to the point that I'm not even going to review the proposal in any detail. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers