SQL学习笔记五去重，给新加字段赋值的方法

去掉数据重复
增加两个字段
alter TABLE T_Employee Add FSubCompany VARchar（20）;
ALTER TABLE T_Employee ADD FDepartment VARCHAR（20）;

给新加的字段赋值
UPDATE T_Employee SET FSubCompany="Beijing",FDepartment="Development" where FNumber="DEV001";
UPDATE T_Employee SET FSubCompany="ShenZhen",FDepartment="Development" where FNumber="DEV002";
UPDATE T_Employee SET FSubCompany="Beijing",FDepartment="HumanResource" where FNumber="HR001";
UPDATE T_Employee SET FSubCompany="Beijing",FDepartment="HumanResource" where FNumber="HR002";
UPDATE T_Employee SET FSubCompany="Beijing",FDepartment="InfoTech" where FNumber="IT001";
UPDATE T_Employee SET FSubCompany="ShenZhen",FDepartment="InfoTech" where FNumber="IT002";
UPDATE T_Employee SET FSubCompany="Beijing",FDepartment="Sales" where FNumber="SALES001";
UPDATE T_Employee SET FSubCompany="Beijing",FDepartment="Sales" where FNumber="SALES002";
UPDATE T_Employee SET FSubCompany="ShenZhen",FDepartment="Sales" where FNumber="SALES003";

查询并去重
select distinct FDepartment from T_Employee

select distinct FDepartment,FSubCompany from T_Employee