> -----Original Message----- > From: pgsql-general-owner@xxxxxxxxxxxxxx [mailto:pgsql-general- > owner@xxxxxxxxxxxxxx] On Behalf Of Jeff Davis > Sent: Monday, August 06, 2012 1:52 PM > To: Andreas Kretschmer > Cc: pg-general > Subject: Re: Range-Types in 9.2 > > On Fri, 2012-08-03 at 10:42 -0700, Jeff Davis wrote: > > On Fri, 2012-08-03 at 17:06 +0200, Andreas Kretschmer wrote: > > > great feature, but i can't find a TIMERANGE, i want to store > > > time-ranges, for instance [10:00:00,16:00:00), how can i do that? > > > > CREATE TYPE timerange AS RANGE ( subtype = time ); > > > > That's the simple answer. I believe we discussed including this as a > > built-in range type at some point, but decided against it. I can't > > remember the reason right now. > > Time of day is a cycle (I forget who pointed this out), so a limit of > 24:00:00 is fairly restrictive. It happens that daytime ranges like > [14:00,15:00) are more common; but it doesn't seem unreasonable to say > [22:00,02:00) either. > > So, an interpretation where time of day has a total order is only useful really > for a daytime schedule (which is still useful, but perhaps not general enough > to include in core). We might be able to make it work as ranges within a 24- > hour cycle, but that will require more thought. > > Regards, > Jeff Davis > Because hours are based upon a zero-cycle it is possible to define a time range as thus: Start: 15:00 End: 03:00 Maximum: 24:00 Minimum: 00:00 { More generalized, can reset to any value } Iterations: 2 Basically a "cyclical range"... The question becomes in what situations would this be more useful than an explicit starting and ending timestamp (with date). It would likely just be easier to create a custom "time" variant that allows for values greater than "24:00" and less-than "00:00" and then create a range from that. Maybe name it "relativetime"... David J. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
