SQL学习笔记五去重，给新加字段赋值的方法(sql基本教程)

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去掉数据重复增加两个字段 alter TABLE T_Employee Add FSubCompany VARchar(); ALTER TABLE T_Employee ADD FDepartment VARCHAR(); 给新加的字段赋值 UPDATE T_Employee SET FSubCompany='Beijing',FDepartment='Development' where FNumber='DEV'; UPDATE T_Employee SET FSubCompany='ShenZhen',FDepartment='Development' where FNumber='DEV'; UPDATE T_Employee SET FSubCompany='Beijing',FDepartment='HumanResource' where FNumber='HR'; UPDATE T_Employee SET FSubCompany='Beijing',FDepartment='HumanResource' where FNumber='HR'; UPDATE T_Employee SET FSubCompany='Beijing',FDepartment='InfoTech' where FNumber='IT'; UPDATE T_Employee SET FSubCompany='ShenZhen',FDepartment='InfoTech' where FNumber='IT'; UPDATE T_Employee SET FSubCompany='Beijing',FDepartment='Sales' where FNumber='SALES'; UPDATE T_Employee SET FSubCompany='Beijing',FDepartment='Sales' where FNumber='SALES'; UPDATE T_Employee SET FSubCompany='ShenZhen',FDepartment='Sales' where FNumber='SALES'; 查询并去重 select distinct FDepartment from T_Employee select distinct FDepartment,FSubCompany from T_Employee

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