SQL查询max(),count() [英] SQL query max(), count()

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本文介绍了SQL查询max(),count()的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

数据库模式看起来像

employee(employee_name,street,city)

works(employee_name,company_name,salary)

公司(company_name,城市)

管理(employee_name,manager_name)

employee(employee_name,street,city)
works(employee_name,company_name,salary)
company(company_name,city)
manages(employee_name,manager_name)

所需执行的查询是:

找到拥有最多员工的公司。

the query needed to do is:
find the company that has the most employees.

我可以通过查询找出最大计数:

I could find out the maximum count by the query:

SELECT max( cnt ) max_cnt
FROM (

SELECT count( employee_name ) cnt, company_name
FROM works
GROUP BY company_name
)w1;

但现在我找不到公司的名字。

But now I can't find out the name of the company. If anyone has some idea please share.

推荐答案

要获取包含最大值的整行,您可以使用 ORDER BY ... DESC LIMIT 1 而不是 MAX

To get the entire row containing the maximum value you can use ORDER BY ... DESC LIMIT 1 instead of MAX:

SELECT company_name, cnt
FROM (
    SELECT company_name, count(employee_name) AS cnt
    FROM works
    GROUP BY company_name
) w1
ORDER BY cnt DESC
LIMIT 1

这篇关于SQL查询max(),count()的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!

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