I am storing the maximum age a vaccination is due in a patient (eg. "don't give this vaccination beyond the age of 10 years" or some such). Some vaccinations are to be given regardless of age. Up to now I have used NULL to mean "no maximum age". That doesn't really feel right and also complicates the SQL needed for retrieving data. I *could*, of course, use something like '999 years' as a special value to indicate "no upper limit" figuring that no one is going to live that long in the foreseeable future. However, the technically elegant and satisfying solution would be to be able to use "infinite" with interval data types much like "infinity" with timestamps. I have tried various syntax attempts, calculations and casts but haven't found any returning an interval of infinite length. The docs and Google don't help, either. I am running 7.4.9 on Debian 4.0. Anyone wants to comment/suggest something ? Thanks, Karsten GNUmed developer -- GPG key ID E4071346 @ wwwkeys.pgp.net E167 67FD A291 2BEA 73BD 4537 78B9 A9F9 E407 1346
