✅EASY MY SQL SOLUTION
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\n# Write your MySQL query statement below\nselect round(sum(temp)/count(distinct player_id), 2) as fraction\nfrom (\n  select\n    player_id,\n    datediff(event_date, min(event_date) over(partition by player_id)) = 1 as temp\n  from \n    Activity\n) as t\n```
['MySQL']