Bruce Momjian <pgman@candle.pha.pa.us> writes: > > Ie, > > > > 10.0.0.0/24 + 1 = 10.0.0.1/24 > > 10.0.0.255/24 + 1 => overflow > > > > Or > > > > 10.1/16 + 1 = 10.1.0.1/16 > > 10.1/16 + 16384 = 10.1.64.0/16 > > 10.1/16 + 65536 => overflow > > So, do not overflow?
You mean not doing modulus arithemtic? Yes. Overflow instead. I see a use case for of generating addresses based on a sequence or some primary key from the database. Something like CREATE SEQUENCE hosts_ip_seq MAXVALUE 65536; ALTER TABLE hosts ALTER ip SET DEFAULT '10.0.0.0/16'::inet + nextval(hosts_ip_seq') Using the primary key or some foreign key in the table would require a trigger which would take too much work to cons up an example for. -- greg ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
