今日真题
题目介绍: The Most Recent Orders for Each Product the-most-recent-orders-for-each-product
难度中等
SQL架构
Table:
代码语言:javascript复制Customers
代码语言:javascript复制 --------------- ---------
| Column Name | Type |
--------------- ---------
| customer_id | int |
| name | varchar |
--------------- ---------
customer_id is the primary key for this table.
This table contains information about the customers.
Table:
代码语言:javascript复制Orders
代码语言:javascript复制 --------------- ---------
| Column Name | Type |
--------------- ---------
| order_id | int |
| order_date | date |
| customer_id | int |
| product_id | int |
--------------- ---------
order_id is the primary key for this table.
This table contains information about the orders made by customer_id.
There will be no product ordered by the same user more than once in one day.
Table:
代码语言:javascript复制Products
代码语言:javascript复制 --------------- ---------
| Column Name | Type |
--------------- ---------
| product_id | int |
| product_name | varchar |
| price | int |
--------------- ---------
product_id is the primary key for this table.
This table contains information about the Products.
Write an SQL query to find the most recent order(s) of each product.
Return the result table sorted by
代码语言:javascript复制product_name
in ascending order and in case of a tie by the
代码语言:javascript复制product_id
in ascending order. If there still a tie, order them by the
代码语言:javascript复制order_id
in ascending order.
The query result format is in the following example:
``` Customers ------------- ----------- | customer_id | name | ------------- ----------- | 1 | Winston | | 2 | Jonathan | | 3 | Annabelle | | 4 | Marwan | | 5 | Khaled | ------------- -----------
Orders ---------- ------------ ------------- ------------ | order_id | order_date | customer_id | product_id | ---------- ------------ ------------- ------------ | 1 | 2020-07-31 | 1 | 1 | | 2 | 2020-07-30 | 2 | 2 | | 3 | 2020-08-29 | 3 | 3 | | 4 | 2020-07-29 | 4 | 1 | | 5 | 2020-06-10 | 1 | 2 | | 6 | 2020-08-01 | 2 | 1 | | 7 | 2020-08-01 | 3 | 1 | | 8 | 2020-08-03 | 1 | 2 | | 9 | 2020-08-07 | 2 | 3 | | 10 | 2020-07-15 | 1 | 2 | ---------- ------------ ------------- ------------
Products ------------ -------------- ------- | product_id | product_name | price | ------------ -------------- ------- | 1 | keyboard | 120 | | 2 | mouse | 80 | | 3 | screen | 600 | | 4 | hard disk | 450 | ------------ -------------- -------
Result table: -------------- ------------ ---------- ------------ | product_name | product_id | order_id | order_date | -------------- ------------ ---------- ------------ | keyboard | 1 | 6 | 2020-08-01 | | keyboard | 1 | 7 | 2020-08-01 | | mouse | 2 | 8 | 2020-08-03 | | screen | 3 | 3 | 2020-08-29 | -------------- ------------ ---------- ------------ keyboard's most recent order is in 2020-08-01, it was ordered two times this day. mouse's most recent order is in 2020-08-03, it was ordered only once this day. screen's most recent order is in 2020-08-29, it was ordered only once this day. The hard disk was never ordered and we don't include it in the result table. ```
代码语言:javascript复制sql
select product_name,product_id,order_id,order_date
from
(
select product_name ,o.product_id ,order_id,order_date ,
rank() over(partition by o.product_id order by order_date desc) rk
from Orders o left join Products p
on o.product_id =p.product_id
)t1
where rk =1
order by product_name,product_id,order_id
- 已经有灵感了?在评论区写下你的思路吧!