我已经为运行查询创建了临时表和数据

CREATE TABLE #Employee(
EmpId  INTEGER NOT NULL,
DeptId INTEGER NOT NULL,
Name   Char(40) NOT NULL,
Age    INTEGER NOT NULL,
Salary INTEGER NOT NULL
);

CREATE TABLE #Department(
DeptId INTEGER NOT NULL,
Name   Char(40) NOT NULL,
Rank   INTEGER NULL
);

INSERT INTO #Employee VALUES(1,1,'A',34,9000000),
                            (2,2,'B',25,450000),
                            (3,1,'C',45,600000),
                            (4,1,'D',23,340000),
                            (5,2,'E',21,580000),
                            (6,3,'F',26,7500000),
                            (7,1,'G',27,650000),
                            (8,2,'H',28,410000),
                            (9,1,'I',29,120000),
                            (10,2,'J',54,150000),
                            (11,3,'I',65,1500000);

INSERT INTO #Department (DeptId,Name) VALUES(1,'Dept 1'),
                                            (2,'Dept 2'),
                                            (3,'Dept 3');

以下是满足您要求的查询
（一）

UPDATE #Department SET RANK=a.Rank
   FROM (SELECT DeptId,AVG(Age) AS 'AvgAge',ROW_NUMBER() OVER (ORDER BY AVG(AGE)DESC,DeptId ASC) AS 'Rank' 
         FROM #Employee GROUP BY DeptId)a 
   WHERE #Department.DeptId=a.DeptId

（二）

SELECT d.Name,SUM(e.Salary) AS 'Total Budget' 
   FROM #Employee e JOIN #Department d 
   ON e.DeptId=d.DeptId 
   GROUP BY d.Name

（三）

SELECT d.Name,AVG(e.Salary) AS 'Avg Sal > 1000000' 
   FROM #Employee e JOIN #Department d 
   ON e.DeptId=d.DeptId
   GROUP BY d.Name HAVING AVG(e.Salary)>1000000