pg.ddx.io  pgsql-sql@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Alvaro Herrera <alvherre@commandprompt.com>
To: Marcin Stępnicki <mstepnicki@gmail.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Finding gaps in scheduled events
Date: Tue, 12 Dec 2006 19:23:08 -0300
Message-ID: <20061212222308.GP22782@alvh.no-ip.org> (raw)
In-Reply-To: <pan.2006.12.12.09.08.15.137773@gmail.com>
References: <pan.2006.12.12.09.08.15.137773@gmail.com>

Marcin Stępnicki wrote:

> Now I need to create a query to find hours at which each of the type can
> start. So, if it's event A (which take 15 minutes) it can start at:
> 
> 8:00 (to 8:15)
> 8:15 (to 8:30)
> ( 8:30 to 8:45 is already taken )
> 8:45 (to 9:00)
> 9:00 (to 9:15)
> 9:15 (to 9:30)
> ( 9:30 to 10:00 (9:30-9:45 and 9:45-10:00) is already taken))
> 10:00 (to 10:15)

I think something like this should help you:

select my_hour
from test_events right join test_timeline on
((start, finish) overlaps (my_hour, my_hour + 15 * '1 minute'::interval))
where start is null;

With your test data, it shows all the times except for 8:30, 9:30 and
9:45.



view thread (5+ messages)  latest in thread

Message-ID: <20061212222308.GP22782@alvh.no-ip.org>
Permalink:  ../20061212222308.GP22782@alvh.no-ip.org/
Also on:    postgresql.org/message-id/20061212222308.GP22782@alvh.no-ip.org

 · 

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-sql@postgresql.org
  Cc: alvherre@commandprompt.com, mstepnicki@gmail.com
  Subject: Re: Finding gaps in scheduled events
  In-Reply-To: <20061212222308.GP22782@alvh.no-ip.org>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox