diff --git a/511-game-play-analysis-i/README.md b/511-game-play-analysis-i/README.md new file mode 100644 index 0000000..58d4427 --- /dev/null +++ b/511-game-play-analysis-i/README.md @@ -0,0 +1,47 @@ +
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. ++ +
+ +
Write an SQL query to report the first login date for each player.
+ +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 | 2016-05-02 | 6 | +| 2 | 3 | 2017-06-25 | 1 | +| 3 | 1 | 2016-03-02 | 0 | +| 3 | 4 | 2018-07-03 | 5 | ++-----------+-----------+------------+--------------+ +Output: ++-----------+-------------+ +| player_id | first_login | ++-----------+-------------+ +| 1 | 2016-03-01 | +| 2 | 2017-06-25 | +| 3 | 2016-03-02 | ++-----------+-------------+ ++