SQLserver 查询时改变字段类型

        cast(A as int) as A,                  字符串 ---> int

           cast(B as int) as B,               字符串 ---> int

           convert(nvarchar(255),C) as C,     int --->  字符串

           convert(nvarchar(255),D) as D,     int --->  字符串

           convert (nvarchar(255) , E) as E   int --->  字符串