1，emp表

2，dept表

3，job表

4，loc表

创建表 复制oracle自带表

create table emp as select * from hr.employees;
create table dept as select * from hr.departments;
create table job as select * from hr.jobs;
create table loc as select * from hr.locations;

工资 ＝ 薪金 ＋ 佣金

1．列出至少有一个员工的所有部门。

• 这里用的是多行子查询 in

select * from dept
where department_id IN 
(SELECT department_id FROM EMP group by department_id);

2,列出薪金比“Alexander”多的所有员工。

select  first_name,salary from emp where salary >
(select