leetcode - 183. Customers Who Never Order

난이도 : Easy

 

 

방법 1

SELECT Customers.name Customers
FROM Customers
     LEFT JOIN Orders ON Customers.id = Orders.customerId
WHERE Orders.id IS NULL

Accepted (41%)

 

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방법 2

SELECT Customers.name Customers
FROM Customers
WHERE id NOT IN (
                 SELECT customerId
                 FROM Orders
                 )

Accepted (81%)

 

 

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