MySQL/183. Customers Who Never Order 从不订购的客户

题目

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代码部分一（869ms 29.11%）

SELECT
    Name AS Customers
    FROM Customers
    LEFT JOIN Orders ON Customers.Id=Orders.CustomerId
    WHERE Orders.CustomerId IS NULL;

 

代码部分二（683ms 38.61%）

SELECT
    Name AS Customers 
    FROM Customers a
    WHERE NOT EXISTS(SELECT * FROM Orders b WHERE a.Id=b.CustomerId);

 

代码部分三（500ms 67.94%）

SELECT
    Name AS Customers
    FROM Customers 
    WHERE Id NOT IN (SELECT CustomerId FROM Orders);