Update row data based on other rows

[Mircea]

What I want to achieve is, while having a grid with one of the columns named "Priority" set to integer, is whenever I change that row value to update all the "priority" values in the other rows to match the new change. Can this be done on key press or loose focus?

example:
having:

3,
1,
2,

If i change the value 1 to 2: the values should update to:

3,
2,
1

Thanks