题目
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);