qq_39387571的博客

select * from emp;select * from dept;-- 92连表查询-- 查询员工信息和部门信息select * from emp e,dept dwhere e.deptno = d.deptno-- 查询员工姓名，部门名称select e.ename,d.dname from emp e,dept d where e.deptno = d.d

数据库，用的还很生，将就这看吧create table Customer( Cusno varchar2(20) primary key, cusname varchar2(20) not null, address varchar2(20), tel varchar2(50) unique);create table produ

-- 这是注释/*多行*/select * from emp;select * from dept;select * from salgrade;select * from bonus;select p.ename,p.sal from emp p;select p.*,p.ename,p.sal from emp p;select emp.ename,em