无法弄清楚查询

Question

有人可以帮我解决下面输出的SQL查询吗？该表位于输出之下。

empno  sal    OtherCollegueID      OtherCollegueSalary
7499   1600   7844                 1500
7521   1250   7876                 1100
7566   2975   7698                 2850
7654   1250   7876                 1100
7698   2850   7782                 2450
7782   2450   7499                 1600
7788   3000   7566                 2975
7839   5000   7788                 3000
7844   1500   7934                 1300
7876   1100   7900                 950
7900   950    7369                 800
7902   3000   7566                 2975
7934   1300   7521                 1250

员工表：

empno   ename   sal   deptno
7369    SMITH   800     20
7499    ALLEN   1600    30
7521    WARD    1250    30
7566    JONES   2975    20
7654    MARTIN  1250    30
7698    BLAKE   2850    30
7782    CLARK   2450    10
7788    SCOTT   3000    20
7839    KING    5000    10
7844    TURNER  1500    30
7876    ADAMS   1100    20
7900    JAMES   950     30
7902    FORD    3000    20
7934    MILLER  1300    10

Answer 1

Dept_no是您与员工的关系。 看起来它似乎要求找到该员工之后薪水最高的同一部门员工的员工ID和工资。

Select t1.emp_no, t1.sal, max(t2.sal) as other_emp_sal
into #temp
from employee t1
join employee t2 on t1.dept = t2.dept and t1.emp_id != t2.emp_id and t2.sal < t1.sal

select t1.*, t2.emp_id
from #temp t1
join employee t2 on t1.dept = t2.dept and t1.other_emp_sal = t2.emp_sal

这应该这样做。

Answer 2

你需要一个窗口函数来取出OtherEmployeeId。这是我的建议：

SELECT x.empno,
x.sal,
x.OtherColleagueId,
x.OtherColleagueSalary
FROM
(SELECT e1.empno,
e1.sal,
e2.empno OtherColleagueId,
e2.sal OtherColleagueSalary,
row_number() OVER (PARTITION BY e1.empno ORDER BY e2.sal DESC) rn
FROM Employee e1
JOIN Employee e2
ON e1.deptno = e2.deptno AND e1.sal > e2.sal) x
WHERE x.rn = 1;