10일차 # 8-11: 테이블 복사 & 테이블에 데이터 여러 건을 한꺼번에 입력

        drop table c_emp purge;

create table c_emp

as

select * from emp where 1=2;

select * from c_emp;

insert into c_emp

 select *

 from emp;

select * from c_emp;

↓ ↓ ↓

drop table c_emp purge;

select * from c_emp;

create table c_emp

as 

select * from emp;

   cf.) 특정 컬럼만 복사하고 컬럼 이름 변경하여 테이블 생성

drop table p_emp purge;

create table p_emp

as select empno as emp_no, ename, sal as salary, deptno

  from emp;

desc p_emp

select * from p_emp;