数据库Mysql的学习(八)-储存过程和事务和导入导出

储存过程
DELIMITER //
CREATE PROCEDURE pro1()
BEGIN
SELECT book_id,book_name,category FROM bookinfo t1
JOIN bookcategory t2
ON t1.book_category_id = t2.category_id;
END//
DELIMITER ;


DELIMITER //
CREATE PROCEDURE pro2(IN cid CHAR(18),OUT num INT)
BEGIN
DELETE FROM reader_info WHERE card_id = cid;
SELECT COUNT(card_id) INTO num FROM readerinfo;
END//
DELIMITER ;

CALL pro2('21513333333',@num);
SELECT @num;

储存过程交换两个数
DELIMITER //
CREATE PROCEDURE pro3(INOUT num1 INT INOUT num2 INT)
BEGIN
DECLARE t INT DEFAULT 0;
SET t=num1;
SET num1=num2;
SET num2=t;
END//
DELIMITER ;

SET @n1=3,@n2=4;
CALL proc3(@n1,@n2);
SELECT @n1,@n2;
DROP PROCEDURE IF EXISTS proc1;


SELECT FLOOR(RAND()*5); 随机数

事务
ROLLBACK 事务回滚 就是不上面写的都不算
COMMIT  事务提交，就是确认
SET autocommit=0  禁止自动提交  =1为开启自动提交


BEGIN
INSERT INTO mytest VALUES(4,'test01');
SAVEPOINT s1;   保存点
INSERT INTO mytest VALUES(4,'test02');
SAVEPOINT s2;  
INSERT INTO mytest VALUES(4,'test03');
ROLLBACK TO s2;
COMMIT;
01 02  会保存  03不会


DELIMITER //
CREATE PROCEDURE borrowproc(cid CHAR(18),bid INT)
BEGIN
DECLARE store_num INT;
DECLARE money FLOAT(7,3);
SELECT store INTO store_num FROM bookinfo WHERE book_id=bid;
SELECT balance INTO money FROM readerinfo WHERE card_id=cid;
SET autocommit=0;  禁止自动提交  同时也是事务的开始
INSERT INTO borrowinfo VALUES(bid,cid,CURDATE()),DATE_ADD(CURDATE(),INTERVAL 1 MONTH),'否');
UPDATE bookinfo SET store=store-1 WHERE book_id=bid;
UPDATE readerinfo SET balance=balance-(SELECT price FROM bookinfo WHERE  book_id=bid)*0.5 WHERE card_id =cid;
IF store_num=0 OR money<=200 THEN
    ROLLBACK;
ELSE 
    COMMIT;
END IF;
END//
DELIMITER ;



存储引擎
SHOW ENGINES;查看支持的引擎
INNODB 安全性能较强
MYISAM 不提供事务 有较高的处理效率
MEMORY 存放临时数据
设置存储引擎
1.my.ini 中 找到default-STORAGE-ENGINE=INNODB  重启mysql
2.set default_storage_engine=INNODB
3.创建表时设置
CREATE TABLE mytest(
 id INT PRIMARY INT,
 NAME VARCHAR(20)
 )ENGINE =INNODB DEFAULT CHARSET=utf-8;
 4.alter TABLE test ENGINE=xxx;
 
 
 
 创建用户
 CREATE USER 'rose'@'localhost' IDENTIFIED BY 'rosepwd'  创建了用户名是rose 主机名是localhost，密码是rosepwd
 //用password的哈希值来创建
 SELECT PASSWORD('roswpwd');
 xxxxxxxxxxxxxxxxxxxxxxx
 CREATE USER 'rose'@'localhost' IDENTIFIED BY PASSWORD ' xxxxxxxxxxxxxxxxxxxxxxx' ;
 
 用grant创建  可以带有权限
 GRANT SELECT,UPDATE ON *.* TO 'testuser'@'localhost' IDENTIFIED BY 'testpwd'; select和update为允许的权限
 删除用户
 DROP USER 'testuser'@'localhost';
 DELETE FROM mysql.user WHERE HOST='hostname'AND USER='username';
 
 
 比如
 GRANT INSERT ,SELECT ON book.* TO 'rose'@'localhost';  为book数据库下所有的表设置查找和插入权限
 FLUSH privileges；  刷新权限表
 GRANT ALL PRIVILEGES ON *.* TO 'rose'@'localhost';为所有东西设置所有权限
 
 
 错误日志
 SHOW VARIABLES ;
 数据库的备份
 mysqldump -uroot -pmy123 book readerinfo >c:mysqlbackup	set1.sql;//备份book下的readerinfo表
 mysqldump -uroot -pmy123 --databases book mytese >c:mysqlbackup	set1.sql;//备份两个多个数据库
 mysqldump -uroot -pmy123 --all-DATABASES >c:mysqlbackup	set1.sql;//备份所有数据库
 恢复
 mysql -uroot -pmy123 book<c:mysqlbackup	set1.sql;恢复数据库下的tset表
 source c:mysqlbackup	set1.sql;  也可以
 
 
 导入导出
 位置不能随便
 my.ini下  找到secure-FILE-priv='xxxxxxxxxxxxx'看这个路径试什么
 你将它设置成null  这不允许导出
 设置成“”则为可以导出到任何位置
 SELECT * FROM book.readerinfo INTO OUTFILE 'xxxxxxxxxxxxxxxx/文件名。txt';这俩路径要一样
 SELECT * FROM book.readerinfo INTO OUTFILE 'xxxxxxxxxxxxxxxx/文件名。txt'
  FIELDS TERMINATED BY ','  设置列与列的分隔符
  LINES TERMINATED BY '
'  设置行末尾换行符
  
  mysql导出文件
  mysql -uroot -pxxxx --execute='语句（执行并推出）' dbname>filename.txt;
  mysql -uroot -pmy123 --execute="select * from readerinfo;" book>"xxxxxxxxxxxx"
  将book数据库下的readerinfo表导出到xxxxxxxxx

  导入命令
LOAD DATA INFILE "xxxxxxxxxxxx" INTO TABLE book.readerinfo;将xxx导入到book下的readerinfo  
mysqlimport -uroot -pmy123 book "xxxxxxxxxxxxxxx";