On Thu, Dec 18, 2003 at 12:21:35 +0000,
teknokrat <teknokrat(at)yahoo(dot)com> wrote:
> I am after an sql query that can give the differnces between consecutive
> timestamp values in the resultset.
> anyone know how to do this?
I think you can do something like the following (untested) on most systems.
select a.stamp - (select max(stamp) from tablename
where tablename.stamp < a.stamp) from tablename;
For postgres this (also untested) might be faster if there is an index
on stamp.
select a.stamp - (select stamp from tablename where tablename.stamp < a.stamp
order by stamp desc limit 1) from tablename;
The above relies on timestamps being unique. The difference for the smallest
timestamp will be null.