TSQL-2008 SUM(X) OVER (PARTITION … ORDER BY CLAUSE)

Question

I really need to take what I have as a result of a CTE, and calculate the cummulative value of groups of data.

The dataset is:

PERIOD  FT  GROUP   DEPT           


        

Answer 1

Simple INNER JOIN should do the trick. Unless I'm misunderstanding you, what you want is a running total, correct?

This example creates a dummy table with dummy data, then uses an inner join for the running total. From a performance standpoint, the Common Table Expression is likely more efficient. But for simplicity, the inner join my be preferential.

/* Dummy table */    

create table testing1
(col1 int not null identity(1,1),
col2 varchar(5),
col3 int)


insert into testing1
values ('a', 10), ('a', 20), ('a', 30), ('b', 40), ('b', 50)

/* Running total example */

SELECT a.col1
           , a.col2
           , a.col3
           , SUM(b.col3) AS total

FROM testing1 a INNER JOIN testing1 b
     ON  a.col1 >= b.col1
     AND a.col2 = b.col2

GROUP BY a.col1, a.col2, a.col3
ORDER BY a.col1



/* Edit to include Output */
col1    col2    col3    total
1   a   10  10
2   a   20  30
3   a   30  60
4   b   40  40
5   b   50  90