Qingqing Zhou <zhouqq.postg...@gmail.com> writes: > Not sure if I understand correctly: in uniqueness check, we see all > possible tuples with a dirty snapshot. For a tuple version inserted > and updated by myself, it is surely dead no matter how the transaction > ends. So I interpret that we can safely pruning the version.
It may be dead in the future, but unless you can prove that your session does not still contain a snapshot that could "see" the row, you can't prune it. Considering only the current query is a fundamental error. 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