以下是我的 EMPLOYEES 表:
create table EMPLOYEES
(EmpID char(4) unique Not null,
Ename varchar(10),
Job varchar(9),
MGR char(4),
Hiredate date,
Salary decimal(7,2),
Comm decimal(7,2),
DeptNo char(2) not null,
Primary key(EmpID),
Foreign key(DeptNo) REFERENCES DEPARTMENTS(DeptNo));
insert into EMPLOYEES values (7839,'King','President',null,'17-Nov-11',5000,null,10);
insert into EMPLOYEES values (7698,'Blake','Manager',7839,'01-May-11',2850,null,30);
insert into EMPLOYEES values (7782,'Clark','Manager',7839,'02-Jun-11',2450,null,10);
insert into EMPLOYEES values (7566,'Jones','Manager',7839,'02-Apr-11',2975,null,20);
insert into EMPLOYEES values (7654,'Martin','Salesman',7698,'28-Feb-12',1250,1400,30);
insert into EMPLOYEES values (7499,'Allen','Salesman',7698,'20-Feb-11',1600,300,30);
insert into EMPLOYEES values (7844,'Turner','Salesman',7698,'08-Sep-11',1500,0,30);
insert into EMPLOYEES values (7900,'James','Clerk',7698,'22-Feb-12',950,null,30);
insert into EMPLOYEES values (7521,'Ward','Salesman',7698,'22-Feb-12',1250,500,30);
insert into EMPLOYEES values (7902,'Ford','Analyst',7566,'03-Dec-11',3000,null,20);
insert into EMPLOYEES values (7369,'Smith','Clerk',7902,'17-Dec-10',800,null,20);
insert into EMPLOYEES values (7788,'Scott','Analyst',7566,'09-Dec-12',3000,null,20);
insert into EMPLOYEES values (7876,'Adams','Clerk',7788,'12-Jan-10',1100,null,20);
insert into EMPLOYEES values (7934,'Miller','Clerk',7782,'23-Jan-12',1300,null,10);
以下是我的 DEPARTMENTS 表:
create table DEPARTMENTS
(DeptNo char(2) unique Not null,
DName varchar(14),
Location varchar(13),
Primary key(DeptNo));
insert into DEPARTMENTS values (10,'Accounting','New York');
insert into DEPARTMENTS values (20,'Research','Dallas');
insert into DEPARTMENTS Values (30,'Sales','Chicago');
insert into DEPARTMENTS values (40,'Operations','Boston');
以下是我的查询:
select ename, salary
from EMPLOYEES
where Salary >
(select AVG(salary)
from EMPLOYEES);
Sql 小提琴演示:http ://www.sqlfiddle.com/#!3/61ca4/1