ORACLE表的基本操作

ORACLE对表的操作，创建表，添加注释，添加列，修改列，删除列，删除表。
创建SEQUENCE

--创建表的基本语句
CREATE TABLE table_name(
	column_name type,
	column_name type,
	column_name type,
	column_name type,
	PRIMARY KEY(column_name)
);
--创建表的例子
CREATE TABLE USER_TBL(
	SEQUENCE_NO VARCHAR2(27),
	USER_ID VARCHAR2(10),
	USER_NAME VARCHAR2(30),
	USER_BIRTH DATE,
	USER_AGE NUMBER(3),
	PRIMARY KEY(SEQUENCE_NO)
);
--添加注释
COMMENT ON TABLE USER_TBL IS '用户信息表';
COMMENT ON COLUMN USER_TBL.SEQUENCE_NO IS '顺番';
COMMENT ON COLUMN USER_TBL.USER_ID IS '用户ID';
COMMENT ON COLUMN USER_TBL.USER_NAME IS '用户名';
COMMENT ON COLUMN USER_TBL.USER_BIRTH IS '出生日期';
COMMENT ON COLUMN USER_TBL.USER_AGE IS '年龄';

--给表添加列
ALTER TABLE USER_TBL ADD COMMENTS VARCHAR2(3000);
COMMENT ON COLUMN USER_TBL.COMMENTS IS '备考';
--给表添加多列
ALTER TABLE USER_TBL ADD(SEX VARCHAR2(1) DEFAULT 'N',
EDUCATION VARCHAR2(10));
COMMENT ON COLUMN USER_TBL.SEX IS '性别';
COMMENT ON COLUMN USER_TBL.EDUCATION IS '学历';

ALTER TABLE USER_TBL ADD TEST VARCHAR2(10);
--修改列属性
ALTER TABLE USER_TBL MODIFY TEST VARCHAR2(5);

--删除列
ALTER TABLE USER_TBL DROP COLUMN TEST; 

--给表重命名
RENAME USER_TBL TO ADMIN_TBL;

--删除表
DROP TABLE ADMIN_TBL;

--创建SEQUENCE
CREATE SEQUENCE SEQ_USER_BLE
	INCREMENT BY 1 
	START WITH 1 
	NOMAXVALUE 
	NOMINVALUE 
	NOCYCLE 
	NOORDER 
	CACHE 10
/
--SEQUENCE应用
SEQ_USER_BLE.NEXTVAL

附件是oralc字段类型详解。