cast time interval to seconds

On Sep 10, 2007, at 10:44 , rihad wrote:

SELECT
(CAST(stop_time AS SECONDS) + 86400 - CAST(start_time AS SECONDS))
% 86400;

"seconds" isn't a datatype. Try extract(epoch from (stop_time -
start_time))

The manual is quite extensive:

http://www.postgresql.org/docs/8.2/interactive/functions-
datetime.html#FUNCTIONS-DATETIME-EXTRACT

Michael Glaesemann
grzm seespotcode net

On Mon, Sep 10, 2007 at 08:44:07PM +0500, rihad wrote:

Hi, I have two columns start_time & stop_time declared as "TIME". I'd
like to compute the difference between the two times in seconds, all in db:

SELECT
(CAST(stop_time AS SECONDS) + 86400 - CAST(start_time AS SECONDS))
% 86400;

At a guess I'd say you should simply subtract the two (ie stop_time -
start_time) and then use extract() to pull the seconds out.

Have a nice day,
--
Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/

2007/9/10, Martijn van Oosterhout <kleptog@svana.org>:

On Mon, Sep 10, 2007 at 08:44:07PM +0500, rihad wrote:

Hi, I have two columns start_time & stop_time declared as "TIME". I'd
like to compute the difference between the two times in seconds, all in db:

SELECT
(CAST(stop_time AS SECONDS) + 86400 - CAST(start_time AS SECONDS))
% 86400;

At a guess I'd say you should simply subtract the two (ie stop_time -
start_time) and then use extract() to pull the seconds out.

Have a nice day,
--
Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/

From each according to his ability. To each according to his ability to litigate.

sample:postgres=# select extract(epoch from time '10:01:30' - time '10:00:00');
date_part
-----------
90
(1 row)

Regards
Pavel Stehule