On Sun, Jan 19, 2014 at 2:17 AM, Peter Geoghegan <p...@heroku.com> wrote: > I'm just throwing an error when locking the tuple returns > HeapTupleInvisible, and the xmin of the tuple is our xid.
I would like some feedback on this point. We need to consider how exactly to avoid updating the same tuple inserted by our command. Updating a tuple we inserted cannot be allowed to happen, not least because to do so causes livelock. A related consideration that I raised in mid to late January that hasn't been commented on is avoiding updating the same tuple twice, and where we come down on that with respect to where our responsibility to the user starts and ends. For example, SQL MERGE officially forbids this, but MySQL's INSERT...ON DUPLICATE KEY UPDATE seems not to, probably due to implementation considerations. -- Peter Geoghegan -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
