找到薪资最少的公司

Question

您好我有以下数据库scheema。

employee (employee-name, street, city)
works (employee-name, company-name, salary)
company (company-name, city)
manages (employee-name, manager-name)

我需要找到工资总额最小的公司。

我写了以下查询，但我的教练告诉我错了。

SELECT company-name
FROM works
GROUP BY company-name
HAVING sum(salary) < ( SELECT sum(salary)
FROM works
GROUP BY company-name)

Answer 1

您的子查询

SELECT company-name, sum(salary)
FROM works
GROUP BY company-name

将为您提供每家公司的累计工资（工资单） 如果您按升序订购这些数据，则第一条记录将是工资单最小的公司。

SELECT company-name, sum(salary)
FROM works
GROUP BY company-name
ORDER BY sum(salary)

您可以使用MySQL的LIMIT子句将该记录集限制为单个记录，使用

SELECT company-name, sum(salary)
FROM works
GROUP BY company-name
ORDER BY sum(salary)
LIMIT 1

Answer 2

我会再给你一个提示。 <是错的（仔细考虑子查询返回的内容）。

Answer 3

我们可以在这种情况下使用< All吗？

e.g。 ：

SELECT company-name
FROM works
GROUP BY company-name
HAVING sum(salary) < ALL( SELECT sum(salary)
FROM works
GROUP BY company-name)