从查询结果中计算不同的值[重复]

Question

我有一个查询SELECT COUNT(TeamID) AS "Team size" FROM tblteamplayers GROUP BY TeamID，它返回每支球队的球员人数，如下所示：

+---+
| 1 |
| 2 |
| 1 |
| 3 |
| 3 |
| 5 |
| 1 |
+---+

但我需要计算每个团队规模在此示例中列出的项目数量：

+---+---+
| 1 | 3 |
| 2 | 1 |
| 3 | 2 |
| 5 | 1 |
+---+---+

Answer 1

在外部查询中再次分组：

SELECT `Team size`, COUNT(*) FROM (
  SELECT   COUNT(*) AS `Team size`
  FROM     tblteamplayers
  GROUP BY TeamID
) t GROUP BY `Team size`