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Date: Fri, 3 Jun 2011 15:52:53 -0400
From: lists-pgsql@useunix.net
To: pgsql-sql@postgresql.org
Subject: selecting records X minutes apart
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I have a table that, at a minimum, has ID and timestamp columns.  Records
are inserted into with random IDs and timestamps.  Duplicate IDs are allowed. 

I want to select records grouped by ID, ordered by timestamp that are X minutes
apart. In this case X is 5.

Note, the intervals are not X minute wall clock intervals, they are X minute
intervals from the last accepted record, per-id.

For instance here is some sample input data:

ID	TS (HH:MM)
-------------------
0	20:00
1	20:03
1	20:04
0	20:05
1	20:05
0	20:08
1	20:09
0	20:10

I'd want the select to return:

ID	TS (HH:MM)
-------------------
0	20:00
0	20:05
0	20:10
1	20:03
1	20:09


Does my question make sense?

Thanks in advance,
Wayne