Oracle Database) subquery, ALTER TABLE

subquery 테이블 복사

ex)

CREATE TABLE dept80
AS
SELECT employee_id, last_name,
salary*12 ANNSAL,
hire_date
FROM employees
WHERE department_id = 80;

 

 

 

ALTER TABLE

읽기 전용 쓰기전용 변경

ex)

ALTER TABLE employees READ ONLY;

ALTER TABLE employees READ WRITE;

 

DROP : 삭제

DROP TABLE dept80;