Initial Commit

priyesh0453 · priyesh0453 · commit 03eef99c339c · 2023-02-13T07:22:31.000+05:30
diff --git a/Easy/1148. Article Views I.sql b/Easy/1148. Article Views I.sql
@@ -0,0 +1,64 @@
+/*
+Table: Views
+
++---------------+---------+
+| Column Name   | Type    |
++---------------+---------+
+| article_id    | int     |
+| author_id     | int     |
+| viewer_id     | int     |
+| view_date     | date    |
++---------------+---------+
+There is no primary key for this table, it may have duplicate rows.
+Each row of this table indicates that some viewer viewed an article (written by some author) on some date. 
+Note that equal author_id and viewer_id indicate the same person.
+
+
+Required Query:
+
+1) Find all the authors that viewed at least one of their own articles.
+
+2) Return the result table sorted by id in ascending order.
+
+
+SQL Schema:
+
+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')
+
+Example:
+
+Input: 
+Views table:
++------------+-----------+-----------+------------+
+| article_id | author_id | viewer_id | view_date  |
++------------+-----------+-----------+------------+
+| 1          | 3         | 5         | 2019-08-01 |
+| 1          | 3         | 6         | 2019-08-02 |
+| 2          | 7         | 7         | 2019-08-01 |
+| 2          | 7         | 6         | 2019-08-02 |
+| 4          | 7         | 1         | 2019-07-22 |
+| 3          | 4         | 4         | 2019-07-21 |
+| 3          | 4         | 4         | 2019-07-21 |
++------------+-----------+-----------+------------+
+Output: 
++------+
+| id   |
++------+
+| 4    |
+| 7    |
++------+
+*/
+
+-- Solution:
+SELECT DISTINCT(author_id) AS id
+FROM Views
+WHERE author_id = viewer_id
+ORDER BY author_id
