On Thu, Jun 14, 2007 at 04:40:12AM -0700, g.hintermayer@xxxxxxxx wrote: > I'd like to convert timestamps without timezone to unix epoch values > with at least microseconds resolution. > but when i do e.g.: > select extract (epoch from timestamp without time zone 'Thu 14 Jun > 05:58:09.929994 2007'); > > i get: > 1181793489.92999 > > so i loose the last digit. I'd expect 1181793489.929994 EXTRACT's return type is double precision, which isn't precise enough to represent that many significant digits. Notice that removing a digit from the beginning gives you another digit at the end: test=> SELECT '1181793489.929994'::double precision; float8 ------------------ 1181793489.92999 (1 row) test=> SELECT '181793489.929994'::double precision; float8 ------------------ 181793489.929994 (1 row) You could convert the epoch value to numeric but you'll have to use a more complex expression; simply casting EXTRACT's result to numeric won't work. One possibility might involve floor and to_char(value, '.US'). -- Michael Fuhr