SQL: Customers Without Orders (LEFT JOIN ... IS NULL)

EasyDatabases

Description

> This problem is paper-only - see explanation for the canonical SQL solution. Given: ``` Customers(id, name) Orders(id, customer_id, total) ``` Return the names of customers who have **never** placed an order, sorted alphabetically. The classic SQL pattern is `LEFT JOIN ... WHERE o.id IS NULL` (the "anti-join"). **For the auto-grader:** implement `customersWithoutOrders(customers, orders)`.

Example 1

Input: customers = [{id:1,name:"Alice"},{id:2,name:"Bob"}], orders = [{id:10,customer_id:1,total:5}]

Output: ["Bob"]

Constraints

- 0 <= customers.length, orders.length <= 10^4

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