Mage <mage@xxxxxxx> writes: > The main question is that isn't "insert into ... select ... where not > exists" atomic? No, it isn't: it *will* fail in the presence of other transactions doing the same thing, because the EXISTS test will only see rows that committed before the command started. You might care to read the manual's chapter about concurrency: http://www.postgresql.org/docs/9.0/static/mvcc.html regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
