sql 别名允许您通过用较短的名称（通常是单个字符）替换表的长名称来键入较少的字符。第8行显示

Posted 2021-05-13

-- WITH ALIASES
SELECT a.CustomerID, a.LastName, b.OrderID, b.Price
FROM Customers2 a
JOIN Orders2 b
WHERE a.CustomerID = b.CustomerID;


-- WITHOUT ALIASES
SELECT Customers2.CustomerID, Customers2.LastName, Orders2.OrderID, Orders2.Price
FROM Customers2 
JOIN Orders2 
WHERE Customers2.CustomerID = Orders2.CustomerID;


-- ALTERNATE EXAMPLE WITH ALIASES
SELECT o.OrderID, o.OrderDate, c.CustomerName
FROM Customers AS c, Orders AS o
WHERE c.CustomerName = "Around the Horn" AND c.CustomerID=o.CustomerID;