Last updated on October 9th, 2024 at 10:32 pm
This Leetcode problem Reported Posts LeetCode Solution is done in SQL.
List of all LeetCode Solution
Level of Question
Easy
Reported Posts LeetCode Solution
Table of Contents
Problem Statement
Column Name | Type |
user_id | int |
post_id | int |
action_date | date |
action | enum |
extra | varchar |
There is no primary key for this table, it may have duplicate rows.
The action column is an ENUM type of (‘view’, ‘like’, ‘reaction’, ‘comment’,’report’, ‘share’).
The extra column has optional information about the action such as a reason for report or a type of reaction.
Write an SQL query that reports the number of posts reported yesterday for each report reason. Assume today is 2019-07-05.
The result format is in the following example.
Example 1:
Input:
user_id | post_id | action_date | action | extra |
1 | 1 | 2019-07-01 | view | null |
1 | 1 | 2019-07-01 | like | null |
1 | 1 | 2019-07-01 | share | null |
2 | 4 | 2019-07-04 | view | null |
2 | 4 | 2019-07-04 | report | spam |
3 | 4 | 2019-07-04 | view | null |
3 | 4 | 2019-07-04 | report | spam |
4 | 3 | 2019-07-02 | view | null |
4 | 3 | 2019-07-02 | report | spam |
5 | 2 | 2019-07-04 | view | null |
5 | 2 | 2019-07-04 | report | racism |
5 | 5 | 2019-07-04 | view | null |
5 | 5 | 2019-07-04 | report | racism |
Output:
report_reason | report_count |
spam | 1 |
racism | 2 |
Explanation:
Note that we only care about report reasons with non zero number of reports.
1. Reported Posts LeetCode Solution MySQL
select extra as report_reason, count(*) as report_count from ( select post_id, extra from Actions where action_date = '2019-07-04' and action = 'report' group by post_id, extra ) as t group by t.extra;
2. Reported Posts LeetCode Solution MySQL (Another approach)
select extra as report_reason, count(distinct post_id) as report_count from Actions where action_date = '2019-07-04' and action = 'report' group by extra;