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SQL学习笔记五去重，给新加字段赋值的方法

　　本文标签：新加字段,赋值

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