UNION操作符

（1）用於合併兩個或多個 SELECT 語句的結果集

（2）預設地，UNION 操作符選取不同的值，如果允許重複的值，請使用 UNION ALL

SELECT E_Name FROM Employees_China
UNION ALL
SELECT E_Name FROM Employees_USA

SELECT INTO 語句

SELECT *
INTO new_table_name [IN externaldatabase] 
FROM old_tablename

SELECT column_name(s)
INTO new_table_name [IN externaldatabase] 
FROM old_tablename

SELECT LastName,Firstname
INTO Persons_backup
FROM Persons
WHERE City='Beijing'

SELECT Persons.LastName,Orders.OrderNo
INTO Persons_Order_Backup
FROM Persons
INNER JOIN Orders
ON Persons.Id_P=Orders.Id_P
 

CREATE TABLE persons_backup(
SELECT persons.LastName, persons.FirstName orders.OrderNo
FROM persons
INNER JOIN orders ON orders.Id_P = persons.Id_P
)