Question

我有两张桌子员工：

employee_number employee_name 工资 divison_id

部门：

division_id 部门名称

如何显示每个部门所有员工的员工编号、员工姓名、部门名称和平均工资。

Answer 1

SELECT employee_number, employee_name, division_name, AVG(amount)
FROM employee
JOIN division ON division.division_id=employee.division_id
GROUP BY division_name;

Answer 2

如果您的数据库支持解析功能，那么您可以按如下方式使用它：

SELECT e.employee_number, e.employee_name, d.division_name, 
       AVG(salary) over (partition by d.division_id) as avg_sal_div
  FROM employee e
  JOIN division d ON d.division_id=e.division_id;

Answer 3

你可以试试：

SELECT employee.employee_number, employee.employee_name, division.division_name, 
    AVG(salary) AS AvgSalary
FROM employee
JOIN division ON division.division_id = employee.division_id
GROUP BY employee_number, employee_name, division_name

但是，我不确定这会达到您想要的结果。

要显示“每个部门所有员工的平均工资”，您可以执行以下操作：

SELECT division.division_name AS Division, AVG(salary) AS AvgSalary FROM division
JOIN employee ON employee.division_id = division.division_id
GROUP BY division_name

sql 用 avg 连接两个表

3 个答案: