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
