> For the complete documentation index, see [llms.txt](https://jaywin.gitbook.io/leetcode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jaywin.gitbook.io/leetcode/solutions/1097-game-play-analysis-v.md).

# 1097. Game Play Analysis V

<https://leetcode.com/problems/game-play-analysis-v>

## Description

Table: `Activity`

```
+--------------+---------+
| Column Name  | Type    |
+--------------+---------+
| player\_id    | int     |
| device\_id    | int     |
| event\_date   | date    |
| games\_played | int     |
+--------------+---------+
(player\_id, event\_date) is the primary key of this table.
This table shows the activity of players of some games.
Each row is a record of a player who logged in and played a number of games (possibly 0) before logging out on someday using some device.
```

The **install date** of a player is the first login day of that player.

We define **day one retention** of some date `x` to be the number of players whose **install date** is `x` and they logged back in on the day right after `x`, divided by the number of players whose install date is `x`, rounded to `2` decimal places.

Write an SQL query to report for each install date, the number of players that installed the game on that day, and the **day one retention**.

Return the result table in **any order**.

The query result format is in the following example.

**Example 1:**

```
**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         | 2016-03-01 | 0            |
| 3         | 4         | 2016-07-03 | 5            |
+-----------+-----------+------------+--------------+
**Output:** 
+------------+----------+----------------+
| install\_dt | installs | Day1\_retention |
+------------+----------+----------------+
| 2016-03-01 | 2        | 0.50           |
| 2017-06-25 | 1        | 0.00           |
+------------+----------+----------------+
**Explanation:** 
Player 1 and 3 installed the game on 2016-03-01 but only player 1 logged back in on 2016-03-02 so the day 1 retention of 2016-03-01 is 1 / 2 = 0.50
Player 2 installed the game on 2017-06-25 but didn't log back in on 2017-06-26 so the day 1 retention of 2017-06-25 is 0 / 1 = 0.00
```

## ac

```java
```