You need GROUP BY to do this ... see
example[
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In this case
select Pid as Id, Description, Sum(DebitAmt) + Sum(CreditAmt) from oneTable GROUP BY Pid, Description ORDER BY Pid
Note this will give you the results mentioned in your post but not necessarily what you actually want ... you mentioned "Id" but "Pid" seems to be the foreign key, and it is somewhat unusual to sum credit and debit amounts together.
[EDIT - :facepalm] I didn't spot the underscore in the descriptions. PIVOT is probably more appropriate for this solution ... see this CodeProject tip
Simple Way To Use Pivot In SQL Query[
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