MySQL 从结果中获取平均值，平均值必须在 8 到 12 之间

Question

所以我试图创建一个 MySQL 查询来获取 RANK id 的平均值，它必须介于 8 到 12 之间，否则查询将选择 5 个随机玩家名称，直到 RANKVALUE 平均在 8 到 12 之间。

select summonername 
from (select rankvalue from 
players group by summonername 
having count(rankvalue) = 5 
order by rand())
group by summonername
having avg(rankvalue) between 8 and 12

---

tid  PLAYER NAME   RANKVALUE
1   summonername2   5
1   Summoner 1      22
1   Summoner 2      10
1   Summoner 3      14
1   Summoner 4      10
1   Summoner 2      21
1   test            21
1   yop             13
1   summonername6   12
1   summonername7   16
1   summonername8   5
1   summonername9   13
1   summonername10  21
1   summonername11  1
1   summonername12  9

Answer 1

使用Group by和Having子句

SELECT `summonername`, AVG(rankvalue)
FROM `players` 
Where tid=1 
group by summonername
Having AVG(rankvalue) between 8 and 12
ORDER BY rand() LIMIT 5