>CREATE TABLE table_name(
>id TINYINT UNSIGNED NOT NULL AUTO_INCREMENT, //id值,无符号、非空、递增——唯一性,可做主键。
>name VARCHAR(60) NOT NULL
>score TINYINT UNSIGNED NOT NULL DEFAULT 0, //设置默认列值
>PRIMARY KEY(id)
>)ENGINE=InnoDB //设置表的存储引擎,一般常用InnoDB和MyISAM;InnoDB可靠,支持事务;MyISAM高效不支持全文检索
>DEFAULT charset=utf8; //设置默认的编码,防止数据库中文乱码
如果有条件的创建数据表还可以使用 >CREATE TABLE IF NOT EXISTS tb_name(........
>CREATE TABLE tb_name2 SELECT * FROM tb_name;//或者部分复制:
>CREATE TABLE tb_name2 SELECT id,name FROM tb_name;
>CREATE TEMPORARY TABLE tb_name(这里和创建普通表一样);
>SHOW TABLES;
>DESCRIBE tb_name;
也可以使用:>SHOW COLUMNS in tb_name; //from也可以
实例:>DROP TABLE IF EXISTS tb_name;
>RENAME TABLE name_old TO name_new;
还可以使用: >ALTER TABLE name_old RENAME name_new;
>ALTER TABLE tb_name ADD[CHANGE,RENAME,DROP] ...要更改的内容...
实例:
>ALTER TABLE tb_name ADD COLUMN address varchar(80) NOT NULL;
>ALTER TABLE tb_name DROP address;
>ALTER TABLE tb_name CHANGE score score SMALLINT(4) NOT NULL;
>INSERT INTO tb_name(id,name,score)VALUES(NULL,'张三',140),(NULL,'张四',178),(NULL,'张五',134);
这里的插入多条数据直接在后边加上逗号,直接写入插入的数据即可;主键id是自增的列,可以不用写。
>INSERT INTO tb_name(name,score) SELECT name,score FROM tb_name2;
>UPDATE tb_name SET score=189 WHERE id=2;
>UPDATE tablename SET columnName=NewValue [ WHERE condition ]
个人理解,存储过程就是一个自定义函数,有局部变量参数,可传入参数,可以返回值,不过这语法够呆滞的~~~
>CREATE PROCEDURE pro(
>IN num INT,OUT total INT)
>BEGIN
>SELECT SUM(score) INTO total FROM tb_name WHERE id=num;
>END;
***这里的 IN (传递一个值给存储过程),OUT(从存储过程传出一个值),INOUT(对存储过程传入、传出),INTO(保存变量)
>CALL pro(13,@total) //这里的存储过程两个变量,一个是IN一个是OUT,这里的OUT也是需要写上的,不写会出错
>SELECT @total //这里就可以看到结果了;
>SHOW PROCEDURE STATUS; //显示当期的存储过程
>DROP PROCEDURE pro; //删除指定存储过程
>CREATE PROCEDURE pro()
>BEGIN
>DECLARE ordername CURSOR FOR
>SELECT order_num FROM orders;
>END;
>OPEN ordername; //打开游标
>CLOSE ordername; //关闭游标
>CREATE TRIGGER trig AFTER INSERT ON ORDERS FOR EACH ROW SELECT NEW.orser_name;
>INSERT语句,触发语句,返回一个值
>DROP TRIGGER trig;
ALTER TABLE table_name
( ADD column datatype [ NULL | NOT NULL ] [ CONSTRAINTS ]
CHANGE column datatype COLUMNS [ NULL | NOT NULL ] [ CONSTRAINTS ]
DROP column,
。。。。
)
>COMMIT;
CREATE INDEX index_name ON tb_name (column [ ASC | DESC ] , .......);
CREATE PROCEDURE pro([ parameters ])
BEGIN
........
END
CREATE TABLE tb_name(
column_name datetype [ NULL | NOT NULL ] [ condtraints] ,
column_name datetype [ NULL | NOT NULL ] [ condtraints] ,
.......
PRIMARY KEY( column_name )
)ENGINE=[ InnoDB | MyiSAM ]DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
CREATE USER user_name [ @hostname ] [ IDENTIFIED BY [ PASSWORD ] 'pass_word' ];
CREATE [ OR REPLACE ] VIEW view_name AS SELECT。。。。。。
DELETE FROM table_name [WHERE ......]
DROP DATEBASE | INDEX | PROCEDURE | TABLE | TRIGGER | USER | VIEW name
INSERT INTO tb_name [ ( columns,...... ) ] VALUES(value1,............);
使用SELECT值插入:
INSERT INTO tb_name [ ( columns,...... ) ]
SELECT columns , ....... FROM tb_name [ WHERE ...... ] ;
ROLLBACK [ TO savapointname ];
SAVEPOINT sp1;
SELECT column_name,.....FROM tb_name [ WHERE ] [ UNION ] [ RROUP BY ] [ HAVING ] [ ORDER BY ]
START TRANSACTION
UPDATE tb_name SET column=value,......[ where ]
原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
如有侵权,请联系 cloudcommunity@tencent.com 删除。
原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
如有侵权,请联系 cloudcommunity@tencent.com 删除。