使用值-1更新表字段值

I'm having a table of users positions, like position 1,2,3,4,5. Now when any user leaves, I will delete that row and I need to update other users position with -1.

e.g.:

If position 2 user leaves, I need to change positions like 3 to 2, 4 to 3, 5 to 4, etc.

Is there any function in mysql that i can use for this type of update?

something like this might work...

update users set position = position-1 where position > 2