嵌套查询的 SQlite 问题

Question

大家好，我一直在努力解决这个问题，但我无法解决它。任何人都可以帮我解决这个问题吗？我很困惑，有人可以帮助我如何修复代码吗？抱歉，我无法上传图片。

SELECT Employee.EmpName, Employee.Age

FROM Employee

WHERE Employee.Age < (SELECT COUNT(Employee.EmployeeID)

FROM Employee, Department

WHERE Department.ManagerID = Employee.EmployeeID 

GROUP BY Employee.EmployeeID

HAVING COUNT(Employee.EmployeeID) >= 2) 

//（问题）找到管理多个部门的最年轻的经理。查询返回经理的姓名和年龄。

架构

Employee(EmployeeID:Integer, EmpName: String, Age: Integer, Salary: Real)
Department(DeptID: Integer, DeptName:String, Budget: Real, ManagerID: Integer)
Works(EmployeeID:Integer, DeptID: Integer, Percent_Time: Integer)

Answer 1

试试这个

SELECT e2.EmpName, e2.Age
FROM Employee e2 
JOIN Works w2 USING (EmployeeID)
JOIN (SELECT w.DeptID, MIN(e.Age) AS Youngest
      FROM Works w 
      INNER JOIN Employee e USING (EmployeeID)
      GROUP BY w.DeptID) sq
  ON w2.DeptID = sq.DeptID and e2.Age = sq.Youngest