leetcode-游戏玩法分析

# Write your MySQL query statement below
select player_id,min(event_date) as first_login from activity a group by player_id ;

这道题我明白了,group by 之后可以使用各种聚合函数例如min,max求值!

来源：CSDN

作者：dogndaxiaodong

链接：https://blog.csdn.net/weixin_41327340/article/details/103788377