Summation

if i have a table like:
id | btype | bnum
1 | 0 | 10
1 | 0 | 5
1 | 10 | 4
1 | 10 | 3

is it possible to use a single SQL command to query the different of "bnum" base on "btype" of id "1". it should be (10+5)-(4+3) =8.

if not, what is the smartest way to do this.

thanks a lot for your kind help.

Yeah... just group by the columns that you want to sum on. In your case, group by id, btype.


SELECT id, btype, SUM(bnum)
FROM table1
GROUP BY id, btype