if a database regularly uses a small number of collations, consider using generated columns to precompute the result of 如果数据库常常使用很少几个排序规则，那么可以考虑使用生成的列预先计算
precompute meaning：[Finance] Method of charging interest in which the annual interest is either deducted from the face amount of the loan when the funds are distributed or is added to the total amount and divided into t...precompute перевод：предварительно вычислять Precompute
