MySQL SELECT function to sum current data

Question

I have a query that return something like this:

| ID | Val |  
| 0  | 10  |     
| 1  | 20  |     
| 2  | 30  |  

But instead of that, I wa

Answer 1

Assuming the table name is t, you can use a query like this:

select t.id, t.val, sum(t2.val) Sum
  from t, t t2
 where t2.id <= t.id
group by t.id, t.val

(tested in Oracle)