lwj的小站

1. 两表合并查询（Combine Two Tables） 题目描述： Table: Person +-------------+---------+ | Column Name | Type | +-------------+---------+ | PersonId | int | | FirstName | varchar | | LastName | v...

Customers Who Never Order 题目描述： Suppose that a website contains two tables, the Customers table and the Orders table. Write a SQL query to find all customers who never order anything. Table: Cust...