On 1 February 2011 01:05, Tom Lane <tgl@xxxxxxxxxxxxx> wrote: > Thom Brown <thom@xxxxxxxxx> writes: >> I've noticed that if I try to use generate_series to include the upper >> boundary of int4, it never returns: > > I'll bet it's testing "currval > bound" without considering the > possibility that incrementing currval caused an overflow wraparound. > We fixed a similar problem years ago in plpgsql FOR-loops... Yes, you're right. Internally, the current value is checked against the finish. If it hasn't yet passed it, the current value is increased by the step. When it reaches the upper bound, since it hasn't yet exceeded the finish, it proceeds to increment it again, resulting in the iterator wrapping past the upper bound to become the lower bound. This then keeps it looping from the lower bound upward, so the current value stays well below the end. -- Thom Brown Twitter: @darkixion IRC (freenode): dark_ixion Registered Linux user: #516935 -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
