# Write your MySQL query statement below
SELECT o.order_date month,count(o.order_id) order_count,count(distinct o.customer_id) customer_count
FROM
(SELECT order_id,date_format(order_date,'%Y-%m') order_date,customer_id,invoiceFROM OrdersWHERE invoice>20
)o
GROUP BY o.order_date
1.3 运行截图
2 仓库经理
2.1 题目内容
2.1.1 基本题目信息
2.1.2 示例输入输出
a 示例输入
b 示例输出
2.2 示例sql语句
SELECT w.name warehouse_name,SUM(w.units*p.v1) volume
FROM Warehouse w
INNER JOIN
(SELECT product_id,width*length*height v1FROM Products
)p
ON w.product_id=p.product_id
GROUP BY w.name
2.3 运行截图
3 三人国家代表队
3.1 题目内容
3.1.1 基本题目信息1
3.1.2 基本题目信息2
3.1.3 示例输入输出
a 示例输入
b 示例输出
3.2 示例sql语句
# Write your MySQL query statement below
SELECT a.student_name member_A,b.student_name member_B,c.student_name member_c
FROM SchoolA a
INNER JOIN SchoolB b
ON a.student_id <> b.student_id AND a.student_name <> b.student_name
INNER JOIN SchoolC c
ON b.student_id <> c.student_id AND b.student_name <> c.student_name
AND a.student_id <> c.student_id AND a.student_name <> c.student_name