摘要:
直接上例子例子中用到的两张表:Employees_China:E_IDE_Name01Zhang, Hua02Wang, Wei03Carter, Thomas04Yang, MingEmployees_USA:E_IDE_Name01Adams, John02Bush, George03Carter, Thomas04Gates, Bill使用 UNION 命令(类似数学中的并集)SELECT E_Name FROM Employees_ChinaUNIONSELECT E_Name FROM Employees_USA结果E_NameZhang, HuaWang, WeiCarter, T 阅读全文