Re: How to store the time zone with a timestamp - Mailing list pgsql-general

We have a TODO also:

        o Allow TIMESTAMP WITH TIME ZONE to store the original timezone
          information, either zone name or offset from UTC [timezone]

          If the TIMESTAMP value is stored with a time zone name, interval
          computations should adjust based on the time zone rules.


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Jim C. Nasby wrote:
> BTW, if you wanted a more integrated solution, you could build a custom
> type that would store the timestamp info. There's a good chance such
> code would end up being what's used in the server as the official type,
> too.
>
> On Fri, Dec 16, 2005 at 08:57:04AM -0800, Andrew B. Young wrote:
> > I just realized that the type "timestamp with time zone" does NOT store
> > the time zone!
> > (And I just found this support list to look for help.)
> >
> > I am developing an application that stores power (watts) readings from
> > meters
> > located around the world (abridged)--
> >    power_meter_id integer NOT NULL,
> >    "ts" timestamp with time zone NOT NULL,
> >    power_reading real NOT NULL
> >
> > Not storing the originating TZ is unacceptable.  My search of this list
> > finds a number of
> > helpful discussions (including a reference to a TODO; soon I hope!)  I
> > don't know
> > database programming and wonder if experienced users could reply with
> > some code
> > they've implemented.
> >
> > I think the best solution is along Karsten's, which I believe goes like
> > this--
> > 1) "ts" timestamp with time zone NOT NULL,
> >     "tz" char( 6 ) NOT NULL,   # '-12:00' to '+13:00'
> > 2) A insert trigger that populates "tz"
> > 3)  Some function foo() that
> >    a) calls timezone( tz, ts ) and
> >    b) tacks on tz to the resulting string
> >  in a "SELECT power_meter_id, foo( ts, tz ), power_reading;"
> >
> > ANY snip its of code that implements anything related would be appreciated.
> > I can probably gin the complete solution seeing enough examples.
> >
> > Thanks!
> > Andrew
> >
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>
> --
> Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
> Pervasive Software      http://pervasive.com    work: 512-231-6117
> vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461
>
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