Question

被问到：展示每个至少有3名员工的部门，部门的名称以及1967年以前出生的该部门的员工数量。

到目前为止我的代码：

`Select department, department_name, numberofemployeesbefore1967 = ( select count(empleyee_id) from employee where year(dateofbirth) < 1967)
From employee inner join department on (department = department_id)
group by department, department_name
having count(*) >=3`

我现在的输出：output

我觉得这是一个非常简单的问题，但我找不到如何只展示1967年之前为该特定部门出生的员工。有人帮帮我吗？

Answer 1

像这样调整子查询......

Select department, department_name, (select count(empleyee_id) from employee where year(dateofbirth) < 1967) AS numberofemployeesbefore1967 From employee inner join department on (department = department_id) group by department, department_name having count(*) >=3

Answer 2

我在主查询中检查年份，在子查询中检查＆gt; = 3

SELECT department department_name, count(*)
FROM department d
JOIN employee e on d.department_id = e.department
WHERE YEAR(dateOfBirth) < 1967 
  AND (SELECT COUNT(*) FROM employee WHERE department = d.department_id) >= 3
GROUP BY d.id, d.name

简单的SQL查询无法解决

2 个答案: