题解 | #获取每个部门中当前员工薪水最高的相关信息#

SELECT dept_no,emp_no,salary as maxSalary
FROM dept_emp
    JOIN salaries USING(emp_no)
WHERE (dept_no,salary) in (
    SELECT dept_no,max(salary)
    FROM dept_emp
        JOIN salaries USING(emp_no)
    GROUP BY dept_no
)
ORDER BY dept_no

1、子表找到每个部门中最高的薪资

SELECT dept_no,max(salary)
    FROM dept_emp
        JOIN salaries USING(emp_no)
    GROUP BY dept_no

2、部门对应薪资的行，并对部门排序

WHERE (dept_no,salary) in (
    SELECT dept_no,max(salary)
    FROM dept_emp
        JOIN salaries USING(emp_no)
    GROUP BY dept_no
)
ORDER BY dept_no

3、完整代码

SELECT dept_no,emp_no,salary as maxSalary
FROM dept_emp
    JOIN salaries USING(emp_no)
WHERE (dept_no,salary) in (
    SELECT dept_no,max(salary)
    FROM dept_emp
        JOIN salaries USING(emp_no)
    GROUP BY dept_no
)
ORDER BY dept_no