mysql : select count when id have multiple same value and calculate percentage

Question

+------+---------+
| id   | object  |
+------+---------+
| 1    |    1    |
| 1    |    2    |
| 1    |    3    |
| 1    |    4    |
+------+---------+

我想选择计数 id 具有相同的值，所以结果是，id 1 有 4 个相同的值，使用 SELECT COUNT( * ) as id1 FROM tablename GROUP BY id

+------+
| id1  | 
+------+
| 4    |   
+------+

我还有另一张 table :

+------+---------+
| id2  | object  |
+------+---------+
| 1    |    1    |
| 1    |    2    |
| 1    |    3    |
| 1    |    4    |
| 1    |    5    |
| 1    |    6    |
| 2    |    1    |
| 2    |    2    |
| 2    |    3    |
| 2    |    4    |
| 2    |    5    |
+------+---------+

如何选择结果的计数，但我仍然不知道如何计算百分比，

+------+---------+
| id1  | id2     |
+------+---------+
|  4   |    6    | # 66%
|  4   |    5    | # 80%
+------+---------+

谢谢大师的帮助。

Answer 1

请尝试这个sqlFiddle

SELECT T1.id as T1ID,
       T2.id as T2ID,
       T1.id1,
       T2.id2,
       T1.id1/T2.id2 * 100 as percentage
FROM
 (SELECT id,count(*) as id1
  FROM tableOne
  GROUP BY id
 )T1,
 (SELECT id,count(*) as id2
  FROM tableTwo
  GROUP BY id
 )T2