없음. 줄여쓰는 것임. https://leetcode.com/problems/customers-who-never-order/ Customers Who Never Order - LeetCode Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview. leetcode.com select name as Customers from Customers as a left outer join Orders as b on a.id = b.customerId where b.id is null select c.name as Cust..