On Thu, Dec 18, 2003 at 12:21:35 +0000, teknokrat <[EMAIL PROTECTED]> 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.
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this may give me difference between current row and oldest row but what I want is row(i).timestamp - row(i-1).timestamp. Also I would like to do it for timestamp values whose hours are within normal working hours i.e 9-5.
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