從COUNT中選擇最大值和最小值-MySQL

Question

我有officecode表的員工，我想只顯示有最大值和最小值的員工officecode，

這是桌子

+----------------+------------+
| employeenumber | officecode |
+----------------+------------+
|           1002 | 1          |
|           1056 | 4          |
|           1076 | 1          |
|           1143 | 7          |
|           1165 | 1          |
|           1166 | 6          |
            ....   .
            ....   .
+----------------+------------+

這就是我想要得到的 ：

+------------+----------+
| officecode | empCount |
+------------+----------+
|           1|         6|
|           7|         2|
+------------+----------+

這是我的方法：

首先，我對它們進行計數和分組

然后從中選擇MAX並與SELECT MIN聯合

但是 SELECT MIN返回錯誤的officecode

這是我的代碼：

SELECT officecode, MAX(empcount) AS 'empcount'
FROM
    (
    SELECT officecode, count(*) AS 'empCount' 
    FROM employees 
    GROUP BY officecode
    )
AS temp

UNION

    SELECT officecode, MIN(empcount) AS 'empcount'
FROM
    (
    SELECT officecode, count(*) AS 'empCount' 
    FROM employees 
    GROUP BY officecode
    )
AS temp2

AS tmp必須在那里，除非它將返回錯誤

它返回了：

+------------+----------+
| officecode | empCount |
+------------+----------+
|           1|         6|
|           1|         2|
+------------+----------+

有人知道我錯了嗎？ 也許您有另一種方法，因為我的方法看起來很糟糕，

Answer 1

(
    SELECT officecode, count(*) AS empCount 
    FROM employees 
    GROUP BY officecode 
    ORDER BY empCount ASC 
    LIMIT 1
) 
UNION ALL
(
    SELECT officecode, count(*) AS empCount 
    FROM employees 
    GROUP BY officecode 
    ORDER BY empCount DESC 
    LIMIT 1
) 

Answer 2

簡單嘗試一下

SELECT officecode,MAX(empcount),MIN(empcount) count(*) AS 'empCount' FROM employees GROUP BY officecode

Answer 3

你需要這個：

SELECT *
FROM
((SELECT ACTION, COUNT(ACTION) FROM t1
GROUP BY ACTION
ORDER BY ACTION DESC
LIMIT 1)
UNION 
(SELECT ACTION, COUNT(ACTION) FROM t1
GROUP BY ACTION
ORDER BY ACTION ASC
LIMIT 1))t

檢查此sqlfiddle： http ://sqlfiddle.com/#!2/7116b5/1

Answer 4

嘗試這個，

SELECT officecode, MAX( empCount ) AS  'empCount'
FROM 
    (
    SELECT officecode, COUNT( * ) AS  'empCount'
    FROM employees 
    GROUP BY officecode ORDER BY empCount DESC 
    ) 
AS temp
UNION
SELECT officecode, MIN( empCount ) AS  'empCount'
FROM 
    (
    SELECT officecode, COUNT( * ) AS  'empCount'
    FROM employees 
    GROUP BY officecode ORDER BY empCount ASC 
    )
AS temp2