delta_attributes 0.0.2

This gem makes updating specified number fields by ActiveRecord in unusual way. Instead of generating sql script to update value in usual way like this: UPDATE users SET money = 10 WHERE id = 1; It replaces it with UPDATE users SET money = money + d WHERE id = 1; where d is difference between old value and new value of that field. This solves problem with simultaneous updating of the same field by different threads. Source code: https://github.com/izbor/delta_attributes