SQL，力扣题目1107，每日新用户统计

news/2024/11/14 20:26:10/

一、力扣链接

LeetCode_1107

二、题目描述

Traffic 表：

+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| user_id       | int     |
| activity      | enum    |
| activity_date | date    |
+---------------+---------+
该表可能有重复的行。
activity 列是 ENUM 类型，可能取 ('login', 'logout', 'jobs', 'groups', 'homepage') 几个值之一。

编写解决方案，找出从今天起最多 90 天内，每个日期该日期首次登录的用户数。假设今天是 2019-06-30 。

以 任意顺序 返回结果表。

三、目标拆解

四、建表语句

Create table If Not Exists Traffic (user_id int, activity ENUM('login', 'logout', 'jobs', 'groups', 'homepage'), activity_date date)
Truncate table Traffic
insert into Traffic (user_id, activity, activity_date) values ('1', 'login', '2019-05-01')
insert into Traffic (user_id, activity, activity_date) values ('1', 'homepage', '2019-05-01')
insert into Traffic (user_id, activity, activity_date) values ('1', 'logout', '2019-05-01')
insert into Traffic (user_id, activity, activity_date) values ('2', 'login', '2019-06-21')
insert into Traffic (user_id, activity, activity_date) values ('2', 'logout', '2019-06-21')
insert into Traffic (user_id, activity, activity_date) values ('3', 'login', '2019-01-01')
insert into Traffic (user_id, activity, activity_date) values ('3', 'jobs', '2019-01-01')
insert into Traffic (user_id, activity, activity_date) values ('3', 'logout', '2019-01-01')
insert into Traffic (user_id, activity, activity_date) values ('4', 'login', '2019-06-21')
insert into Traffic (user_id, activity, activity_date) values ('4', 'groups', '2019-06-21')
insert into Traffic (user_id, activity, activity_date) values ('4', 'logout', '2019-06-21')
insert into Traffic (user_id, activity, activity_date) values ('5', 'login', '2019-03-01')
insert into Traffic (user_id, activity, activity_date) values ('5', 'logout', '2019-03-01')
insert into Traffic (user_id, activity, activity_date) values ('5', 'login', '2019-06-21')
insert into Traffic (user_id, activity, activity_date) values ('5', 'logout', '2019-06-21')

五、过程分析

1、找出用户第一天登录的日期

2、找出第一天登录日期与指定日期间隔90天以内的日期，并计算人数

六、代码实现

with t1 as(
select user_id, activity, activity_date, row_number() over(partition by user_id order by activity_date) rn
from Traffic
where activity = 'login' 
)
select activity_date login_date, count(user_id) user_count
from t1 
where rn = 1
and datediff('2019-06-30', activity_date) <= 90
group by activity_date;