am Sun, dem 28.01.2007, um 10:25:33 -0600 mailte Ron Johnson folgendes:
> Hi.
>
> These fields do not use any disk space, as the data in them is
> derived on the fly.
>
> For example:
> CREATE TABLE T_EXAMPLE (
> SOME_DATE DATE,
> JDATE COMPUTED BY EXTRACT(JULIAN FROM SOME_DATE)
> );
>
> A work-around is to create a function, and reference it in every
> query, but storing them in the table definition is the "tidy",
> low-maintenance way to do it.
Was this a question how to do this in PostgreSQL?
You can use a VIEW. Just create T_EXAMPLE ( SOME_DATE DATE );
and then
CREATE VIEW view_example AS SELECT some_date, EXTRACT(JULIAN FROM
some_date) AS julian_date FROM T_EXAMPLE;
Andreas
--
Andreas Kretschmer
Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
