Re: How to perform calculations on 'time' and 'interval' datatypes

On Tue, Nov 28, 2000 at 02:16:58PM +0100, Marcin Bajer wrote:
> I do for example a
> SELECT departure1, departure+600::intervals as departure2,
> departure+1000::intervals as departure3, ...
>
> and then departure1 is of time type, but departure2 and following are of
> interval type

Would timestamp be recommended over time? Also, interval can handle things
in the form 'x hour y min'.

Example, from something I'm working on now:

tv=> \d shows
Table "shows"
Attribute | Type | Modifier
-------------+-----------+----------------------------------------------------
title | text | not null
story | text |
channel | integer | not null
start | timestamp | not null
length | interval | not null
status | char(1) | default 'U'
description | text |
comment | text |
number | integer | not null default
nextval('shows_number_seq'::text)
Indices: shows_number_key,
shows_start_channel,
shows_title_story
Constraint: (strpos('ARUW'::text, (status)::text) > 0)

tv=> select start from shows where number=1;
start
------------------------
2000-11-22 10:00:00-06
(1 row)

tv=> update shows set start=start + interval '5 min' where number=1;
UPDATE 1
tv=> select start from shows where number=1;
start
------------------------
2000-11-22 10:05:00-06
(1 row)

mrc
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