customers-who-never-order.

Author: the1Riddle

MySQL/customers-who-never-order.sql

@@ -1,7 +1,13 @@
 # Time:  O(n^2)
 # Space: O(1)
 
-SELECT Name AS Customers FROM Customers WHERE Id NOT IN (SELECT CustomerId FROM Orders)
+SELECT Name AS Customers 
+FROM Customers 
+WHERE Id NOT IN (SELECT CustomerId FROM Orders)
 
-SELECT Customers.Name AS Customers FROM (Customers LEFT JOIN Orders ON Customers.Id = Orders.CustomerId) WHERE Orders.CustomerId IS NULL
+  /** solution two */
+
+SELECT Customers.Name AS Customers 
+FROM (Customers LEFT JOIN Orders ON Customers.Id = Orders.CustomerId) 
+WHERE Orders.CustomerId IS NULL