自定义SQL查询按范围或组计数

Question

在此示例中，如何使用SQL返回工资带的员工数量？

sip_cid_type

Answer 1

试试这个：

select s.name, count(*) as count
from employeesalary e
inner join salarybands s on e.salary >= s.minsalary and e.salary <=s.maxsalary
group by s.name

关键的想法是根据每个员工的薪水范围来加入表格。然后按照通常的方式实施计算。

Demo

Answer 2

非连接非常适合您的需求。它是一个不使用等价运算符来匹配行的连接。

SELECT
  sb.name,
  count(*)
FROM
  EmployeeSalary es
  INNER JOIN SalaryBands sb ON
    es.salary BETWEEN sb.minsalary AND sb.maxsalary
GROUP BY sb.name

Answer 3

另一种不需要连接的方法。

select 
sum(case when REPLACE(salary, ',', '') between 20000 and 24999) then 1 else 0 end as count_tier1,
sum(case when REPLACE(salary, ',', '') between 25000 and 44999) then 1 else 0 end as count_tier2,
sum(case when REPLACE(salary, ',', '') between 45000 and 150000) then 1 else 0 end as count_tier3
from
Employee_salary
;