Thank you for your advices. I actually would like to store GPS coordinates, but anonymously, so I was going to save md5(my_secret+IMEI) coming from a mobile... I have to lookup if uuid is supported there Regards Alex On Sat, Oct 16, 2010 at 11:08 PM, Rob Sargent <robjsargent@xxxxxxxxx> wrote: > Merlin Moncure wrote: >> why don't you use the bytea type, and cut the key size down 50%? You >> can always format it going out the door if you want it displayed hex. >> Besides being faster, you get to skip the 'is hex' regex. >> >> create table foo(id bytea check(length(id) = 16)); >> insert into foo values (decode(md5('a'), 'hex')); -- if not using pgcrypto >> insert into foo values (digest('b', 'md5')); -- if using pgcrypto >> (preferred) >> >> select encode(id, 'hex') from foo; > > Why not the support uuid type instead. Aren't md5s only as unique as the > source? i.e. The same value hashed results in the same md5, no? -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general