我有一个电话要问我们商店的玩家数量，总的总数比单独的总数加起来还少。我不知道为什么会这样。

SELECT (SELECT
         COUNT(DISTINCT (playerid))
       FROM playerhistory
       WHERE MONTH(from_unixtime(checkouttime)) = 11
       AND YEAR(from_unixtime(checkouttime)) = 2018
       AND storeid > 100
       AND howmuchplayed > 0)
       AS total,
       (SELECT
         COUNT(DISTINCT (playerid))
       FROM playerhistory
       WHERE MONTH(from_unixtime(checkouttime)) = 11
       AND YEAR(from_unixtime(checkouttime)) = 2018
       AND storeid = 12786
       AND howmuchplayed > 0)
       AS ra,
       (SELECT
         COUNT(DISTINCT (playerid))
       FROM playerhistory
       WHERE MONTH(from_unixtime(checkouttime)) = 11
       AND YEAR(from_unixtime(checkouttime)) = 2018
       AND storeid = 12801
       AND howmuchplayed > 0)
       AS mp,
       (SELECT
         COUNT(DISTINCT (playerid))
       FROM playerhistory
       WHERE MONTH(from_unixtime(checkouttime)) = 11
       AND YEAR(from_unixtime(checkouttime)) = 2018
       AND storeid = 12830
       AND howmuchplayed > 0)
       AS cy,
       (SELECT
         COUNT(DISTINCT (playerid))
       FROM playerhistory
       WHERE MONTH(from_unixtime(checkouttime)) = 11
       AND YEAR(from_unixtime(checkouttime)) = 2018
       AND storeid = 13389
       AND howmuchplayed > 0)
       AS ne,
       (SELECT
         COUNT(DISTINCT (playerid))
       FROM playerhistory
       WHERE MONTH(from_unixtime(checkouttime)) = 11
       AND YEAR(from_unixtime(checkouttime)) = 2018
       AND storeid = 13600
       AND howmuchplayed > 0)
       AS lm,
       (SELECT
         COUNT(DISTINCT (playerid))
       FROM playerhistory
       WHERE MONTH(from_unixtime(checkouttime)) = 11
       AND YEAR(from_unixtime(checkouttime)) = 2018
       AND storeid = 13694
       AND howmuchplayed > 0)
       AS ch

结果如下： total | ra | mp | cy | ne | lm | ch 303 | 34 | 74 | 27 | 43 | 75 | 53 正如你所看到的，总数是303，但当你把ra，mp，cy，ne，lm和ch加起来，就变成306了
表中没有其他storeid： select distinct(storeid) from playerhistory where storeid > 100 结果： storeid 12786 12801 12830 13389 13600 13694 我的查询有缺陷吗？为什么不加起来？
谢谢你的帮助。