2020-10-13

Oracle学习笔记四:表的创建与管理

一、表的创建

1.1、创建表

CREATE TABLE STUDENT ( ID INT NOT NULL, NAME VARCHAR2(20), BIRTHDAY DATE, STATUS VARCHAR2(10), CONSTRAINT STUDENT_PK PRIMARY KEY  (  ID  ) ENABLE );

1.2、插入数据

INSERT INTO STUDENT (ID,NAME,BIRTHDAY,STATUS) VALUES (1,'HELLO',TO_DATE('2000-01-01','yyyy-mm-dd'),'GOOD');INSERT INTO STUDENT (ID,NAME,BIRTHDAY,STATUS) VALUES (2,'WORLD',TO_DATE('2000-02-01','yyyy-mm-dd'),'GOOD');COMMIT;

1.3、查看所有表

SELECT * FROM TAB;SELECT * FROM USER_TABLES;

二、表的更改

2.1、更改表名

RENAME STUDENT TO STUDENT1;

2.2、更改表结构

--增加列ALTER TABLE STUDENT ADD (EMAIL VARCHAR2(50));--增加列默认值ALTER TABLE STUDENT MODIFY (BIRTHDAY DEFAULT SYSDATE);--更改列名ALTER TABLE STUDENT RENAME COLUMN STATUS TO INITLEVEL;--更改列类型ALTER TABLE STUDENT MODIFY (NAME VARCHAR2(10 BYTE));--删除列ALTER TABLE STUDENT DROP COLUMN STATUS;

三、表的复制

CREATE TABLE STUDENT01 AS SELECT * FROM STUDENT;

四、表的截断

TRUNCATE TABLE STUDENT01;

五、表的删除

--删除表TRUNCATE TABLE STUDENT01;--删除表(包含约束)DROP TABLE STUDENT01 CASCADE CONSTRAINTS;--删除表(释放资源,不经过回收站。)DROP TABLE STUDENT01 PURGE;

六、表的增删改查

6.1、insert

--直接插入INSERT INTO STUDENT01 (ID,NAME,BIRTHDAY,STATUS) VALUES (3,'HI',TO_DATE('2000-03-01','yyyy-mm-dd'),'GOOD');INSERT INTO STUDENT01 (ID,NAME,BIRTHDAY,STATUS) VALUES (4,'MAN',TO_DATE('2000-04-01','yyyy-mm-dd'),'GOOD');COMMIT;--从其它表插入INSERT INTO STUDENT (ID,NAME,BIRTHDAY,STATUS)SELECT ID,NAME,BIRTHDAY,STATUS FROM STUDENT01 WHERE NOT EXISTS (SELECT 1 FROM STUDENT WHERE ID=STUDENT01.ID);COMMIT;

6.2、delete

 

6.3、update

 

6.4、select

 

原文转载:http://www.shaoqun.com/a/481002.html

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一、表的创建1.1、创建表CREATETABLESTUDENT(IDINTNOTNULL,NAMEVARCHAR2(20),BIRTHDAYDATE,STATUSVARCHAR2(10),CONSTRAINTSTUDENT_PKPRIMARYKEY(ID)ENABLE);1.2、插入数据INSERTINTOSTUDENT(ID,NAME,BIRTHDAY,STATUS)VALUES(1,'
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