``` Users 表单: +------+-----------+ | id | name | +------+-----------+ | 1 | Alice | | 2 | Bob | | 3 | Alex | | 4 | Donald | | 7 | Lee | | 13 | Jonathan | | 19 |...

题目介绍： 购买了产品A和产品B却没有购买产品C的顾客 customers-who-bought-products-a-and-b-but-not-c

``` Stocks 表: +---------------+-----------+---------------+--------+ | stock_name | operation | operation_day | price | +---------------+-----------+-----------...

题目介绍： 按年度列出销售总额 total-sales-amount-by-year

题目介绍： 使用唯一标识码替换员工ID replace-employee-id-with-the-unique-identifier

题目介绍： 获取最近第二次的活动 get-the-second-most-recent-activity

题目介绍： 顾客的可信联系人数量 number-of-trusted-contacts-of-a-customer

可以以任何顺序返回结果，Activities 表的每项活动的参与者都来自 Friends 表

题目介绍： 院系无效的学生 students-with-invalid-departments

``` Movies 表： +-------------+--------------+ | movie_id | title | +-------------+--------------+ | 1 | Avengers | | 2 | Frozen 2 | | 3 | Joker | +-------------+...