# 1148. 文章浏览 I
# https://leetcode-cn.com/problems/article-views-i/

# SQL架构
Create table If Not Exists Views (article_id int, author_id int, viewer_id int, view_date date);
Truncate table Views;
insert into Views (article_id, author_id, viewer_id, view_date) values ('1', '3', '5', '2019-08-01');
insert into Views (article_id, author_id, viewer_id, view_date) values ('1', '3', '6', '2019-08-02');
insert into Views (article_id, author_id, viewer_id, view_date) values ('2', '7', '7', '2019-08-01');
insert into Views (article_id, author_id, viewer_id, view_date) values ('2', '7', '6', '2019-08-02');
insert into Views (article_id, author_id, viewer_id, view_date) values ('4', '7', '1', '2019-07-22');
insert into Views (article_id, author_id, viewer_id, view_date) values ('3', '4', '4', '2019-07-21');
insert into Views (article_id, author_id, viewer_id, view_date) values ('3', '4', '4', '2019-07-21');

# Write your MySQL query statement below
select
    distinct author_id as id
from
    Views
where
    author_id = viewer_id
order by
    id;

# clean-up
drop table Views;