Question

我有员工使用officecode表，我想用 max 和 min 员工显示officecode ONLY ，

这是表格

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

这就是我想要：

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

这是我的方法：

首先我COUNT和GROUP他们

然后从中选择MAX并使用SELECT MIN UNION它

但 SELECT MIN返回错误的officecode

这是我的代码：

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必须在那里，除非它会返回错误

它返回了：

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

任何知道我错的人吗？或者你有另一种方法因为我的方法看起来如此loooooong，thx

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

简单试试这个

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

Answer 3

你需要这个：

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

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

Answer 4

试试这个，

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

从COUNT中选择MAX和MIN - MySQL

4 个答案: