Game Play Analysis IV

Task: Report the fraction of players that logged in again on the day after the day they first logged in.

Table: Activity

+--------------+------+
| Column Name  | Type |
+--------------+------+
| player_id    | INT  |
| device_id    | INT  |
| event_date   | date |
| games_played | INT  |
+--------------+------+

Input: Activity table:

+-----------+-----------+------------+--------------+
| player_id | device_id | event_date | games_played |
+-----------+-----------+------------+--------------+
| 1         | 2         | 2016-03-01 | 5            |
| 1         | 2         | 2016-03-02 | 6            |
| 2         | 3         | 2017-06-25 | 1            |
| 3         | 1         | 2016-03-02 | 0            |
| 3         | 4         | 2016-03-03 | 5            |
+-----------+-----------+------------+--------------+

Output:

+----------+
| fraction |
+----------+
| 0.67     |
+----------+