SQL

Join

• INNER JOIN(Join)
  在表中存在至少一个匹配时，INNER JOIN 关键字返回行。

SELECT Persons.LastName, Persons.FirstName, Orders.OrderNo
FROM Persons
INNER JOIN Orders
ON Persons.Id_P=Orders.Id_P
ORDER BY Persons.LastName

• LEFT JOIN

SELECT Persons.LastName, Persons.FirstName, Orders.OrderNo
FROM Persons
LEFT JOIN Orders
ON Persons.Id_P=Orders.Id_P
ORDER BY Persons.LastName

• RIGHT JOIN

SELECT Persons.LastName, Persons.FirstName, Orders.OrderNo
FROM Persons
FULL JOIN Orders
ON Persons.Id_P=Orders.Id_P
ORDER BY Persons.LastName

• FULL JOIN

FROM Persons
FULL JOIN Orders
ON Persons.Id_P=Orders.Id_P
ORDER BY Persons.LastName