Question

我想找到数量较少的工作，但是我不能在hading子句上使用min函数。

SELECT JOB, COUNT(*) AS "NUMBER OF EMPLOYEES"
FROM EMP
GROUP BY JOB
HAVING COUNT(*) = MIN(COUNT(*))
ORDER BY JOB

Answer 1

您可以像这样使用FETCH子句

SELECT JOB, COUNT(*) AS "NUMBER OF EMPLOYEES"
FROM EMP
GROUP BY JOB
ORDER BY "NUMBER OF EMPLOYEES"
FETCH FIRST ROW ONLY

哦！其oracle 11g，然后使用以下命令：

SELECT JOB, COUNT(*) AS "NUMBER OF EMPLOYEES"
FROM EMP
GROUP BY JOB
HAVING COUNT(*) = (SELECT MIN(COUNT(*)
FROM EMP GROUP BY JOB)
ORDER BY JOB

干杯！

Answer 2

您要计算每个职位的员工数。然后，您想要显示员工人数最少的工作。这是两个步骤。

一种方法：

select job, employees
from
(
  select job, count(*) as employees, min(count(*)) over () as min_employees
  from emp
  group by job
)
where employees = min_employees;

另一个：

with jobs as (select job, count(*) as employees from emp group by job)
select *
from jobs
where employees = (select min(employees) from jobs);

我不能在Oracle中使用min和max

2 个答案: