mysql(2) 数据的insert-delete-update

PS:TINYINT取值范围(-128-127,0-255);auto_increment自动编号

USE db;

CREATE  TABLE student

(

        sno INT UNSIGNED NOT NULL AUTO_INCREMENT,

         sname  VARCHAR(20)  NOT NULL,

        sage TINYINT UNSIGNED NOT NULL,

        sbirthday DATETIME,

       saddress VARCHAR(50),

       sscore DECIMAL(4,1),/*999.9*/

      PRIMARY KEY(sno),

)ENGINE=MYISAM AUTO_INCREMENT=201401 DEFAULT CHARSET=utf8;

DESC  student;

-------------------------------------------------------------------------------------------------------------------

1)INSERT 操作  插入数据

INSERT INTO student VALUES(NULL,'李四',18,'2000-1-8','安徽',82);

INSERT student VALUES(NULL,'张三',19,'1999-7-18','北京',90);

INSERT INTO STUDENT VALUES(NULL,'LILI',20,'1998-2-9','HUBIE',89),(NULL,'LICI',21,'Hong Kong',70 );

---把表中信息查询出来,并插入(insert into select * from t)

INSERT INTO student (sname,sage,sbirthday,saddress,ssore) SELECT sname,sgae,sbirthday,saddress,sscore FROM student;

INSERT INTO student (sname,sage) VALUES ('jack',18),('Amy',22);

----如果id相同替换插入:

 REPLACE  INTO  student (sname,sage) VALUES ('张默默',18),('李丽丽',19);

REPLACE INTO student VALUES(201436,'AAA',22,'2001-2-3','SHANGHAI',78);

--查看查询数据显示

SELECT * FORM  student;

2)修改数据

UPDATE  student  SET  sscore=89,saddress='北京'  WHERE sno=201401;

3)删除数据

DELECT  FORM  student WHERE sno=201401;

DELECT  FORM  student;/*无条件删除所有数据*/

TRUNCATE TABLE student;/*直接清空数据表记录,auto_increment自动编号从1重新分配*/