subtract from sum

calculate the sum of points from on col and then subtract a value

[phparion]

i have a user table in which one col is named as POINTS.

it contains the points of user gained from different events.

now i want to subtract a specific value from the total points that i get using SUM(point) mysql function.

i have written a query that is wrong but it will give you the idea what i am looking to do.

say i want to subtract 100 points from user then i am using query like

update users set SUM(points - 100)

please guide me how can i do this. thanks