利用Sakila数据库练习SQL查询

查询所有电影的数量

SELECT COUNT(*) AS total_moviesFROM film;

查询所有电影的平均租金

SELECT AVG(rental_rate) AS avg_rental_rateFROM film;

查询电影库存大于10的电影名称和库存量

SELECT title, inventory_idFROM filmWHERE inventory_id > 10;

查询租借记录中每个客户借阅电影的总数量

SELECT customer_id, COUNT(*) AS total_rentalsFROM rentalGROUP BY customer_id;

查询最近一个月内租借次数最多的电影

SELECT film_id, COUNT(*) AS total_rentalsFROM rentalWHERE rental_date >= DATE_SUB(NOW(), INTERVAL 1 MONTH)GROUP BY film_idORDER BY total_rentals DESCLIMIT 1;