On fös, 2006-12-15 at 18:27 +0600, Partha Guha Roy wrote:
> Hi,
>
> I have a table that contains data like this:
>
> ID ATIME (MM/dd/yyyy)
> == ====
> 1 10/12/2006
> 2 10/14/2006
> 3 10/18/2006
> 4 10/22/2006
> 5 10/30/2006
>
> Now I need a query that will subtract atime of row 1 from row 2, row2
> from row3 and so on...
if there are no missing IDs you can use a self join
SELECT t1.atime,t2,atime
FROM t AS t1
JOIN t AS t2 ON (t1.ID=t2.ID+1)
otherwise, you could use a loop in a pl/pgpsql function
gnari