James Kitambara wrote:
> Dear Srikanth,
> You can solve your problem by doing this
>
> THE SQL IS AS FOLLOWS
> ASSUME TIME INTERVAL 2008-12-07 07:59:59 TO 2008-12-07 08:58:59 AND THE TABLE NAME time_interval
>
> COUNT (*) FROM
> (select customer_id, log_session_id, start_ts, end_ts , end_ts-start_ts as "Interval" from time_interval
> where end_ts-start_ts >= '1 hour'
> and '2008-12-07 07:59:59' between start_ts and end_ts)
> AS COUNT ;
Another way to phrase the WHERE clause is with the OVERLAPS operator,
something like this:
WHERE (start_ts, end_ts) OVERLAPS ('2008-12-07 07:59:59', '2008-12-07 08:59:59')
What I'm not so sure about is how optimizable this construct is.
--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.