加入收藏 | 设为首页 | 会员中心 | 我要投稿 李大同 （https://www.lidatong.com.cn/）- 科技、建站、经验、云计算、5G、大数据,站长网!
当前位置： 首页 > 站长学院 > MySql教程 > 正文

MYSQL数据库MySQL备份与恢复之热备（3）

发布时间：2020-12-12 01:14:27 所属栏目：MySql教程 来源：网络整理
导读：《MYSQL数据库MySQL备份与恢复之热备（3）》要点： 本文介绍了MYSQL数据库MySQL备份与恢复之热备（3），希望对您有用。如果有疑问，可以联系我们。 ?????? 在上两篇文章(MySQL备份与恢复之冷备,MySQL备份与恢复之真实环境使用冷备)中,我们提到了冷备和真实环

《MYSQL数据库MySQL备份与恢复之热备（3）》要点：
本文介绍了MYSQL数据库MySQL备份与恢复之热备（3），希望对您有用。如果有疑问，可以联系我们。

?????? 在上两篇文章(MySQL备份与恢复之冷备,MySQL备份与恢复之真实环境使用冷备)中,我们提到了冷备和真实环境中使用冷备.那从这篇文章开始我们看下热备.显然热备和冷备是两个相对的概念,冷备是把数据库服务,比如MySQL,Oracle停下来,然后使用拷贝、打包或者压缩命令对数据目录进行备份；那么我们很容易想到热备就是在MySQL或者其他数据库服务在运行的情况下进行备份.但是,这里存在一个问题,因为生产库在运行的情况下,有对该库的读写,读写频率有可能高,也可能低,不管频率高低,总会就会造成备份出来的数据和生产库中的数据不一致的情况.热备这段时间,其他人不可以操作是不现实的,因为你总不可能终止用户访问Web程序.要解决这个问题,可以采用指定备份策略,比如哪个时间段进行备份,备份哪些数据等等,总之,保证数据的完整性和一致性,切记,备份重于一切!!!
?????? 热备可以对多个库进行备份,可以对单张表或者某几张表进行备份.但是无法同时备份多个库多个表,只有分开备份.下面我们看下热备的示意图,并进行热备模拟.
示意图MYSQL入门

?MYSQL入门

热备模拟MYSQL入门

1、对单个库进行备份
第一步,移除LVM快照.(如果没有创建,忽略此步)
MYSQL入门

[root@serv01 data]# lvremove /dev/data/smydata 
Do you really want to remove active logical volume smydata? [y/n]: y
 Logical volume "smydata" successfully removed

第二步,设置MySQL的密码
MYSQL入门

mysql> set password=password("123456");
Query OK,0 rows affected (0.00 sec)

第三步,查看MySQL是否启动.因为是热备,所以要求MySQL服务启动
MYSQL入门

[root@serv01 data]# /etc/init.d/mysqld status
 SUCCESS! MySQL running (2664)

第四步,导出单个数据库
MYSQL入门

[root@serv01 data]# cd /databackup/
#本质是导出为SQL
[root@serv01 databackup]# mysqldump -uroot -p123456 --database larrydb
-- MySQL dump 10.13 Distrib 5.5.29,for Linux (x86_64)
--
-- Host: localhost Database: larrydb
-- ------------------------------------------------------
-- Server version 5.5.29-log
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;
/*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */;
/*!40103 SET TIME_ZONE='+00:00' */;
/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS,UNIQUE_CHECKS=0 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS,FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE,SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES,SQL_NOTES=0 */;
--
-- Current Database: `larrydb`
--
CREATE DATABASE /*!32312 IF NOT EXISTS*/ `larrydb` /*!40100 DEFAULT CHARACTER SET latin1 */;
USE `larrydb`;
--
-- Table structure for table `class`
--
DROP TABLE IF EXISTS `class`;
/*!40101 SET @saved_cs_client = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `class` (
 `cid` int(11) DEFAULT NULL,`cname` varchar(30) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;
--
-- Dumping data for table `class`
--
LOCK TABLES `class` WRITE;
/*!40000 ALTER TABLE `class` DISABLE KEYS */;
INSERT INTO `class` VALUES (1,'linux'),(2,'oracle');
/*!40000 ALTER TABLE `class` ENABLE KEYS */;
UNLOCK TABLES;
--
-- Table structure for table `stu`
--
DROP TABLE IF EXISTS `stu`;
/*!40101 SET @saved_cs_client = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `stu` (
 `sid` int(11) DEFAULT NULL,`sname` varchar(30) DEFAULT NULL,`cid` int(11) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;
--
-- Dumping data for table `stu`
--
LOCK TABLES `stu` WRITE;
/*!40000 ALTER TABLE `stu` DISABLE KEYS */;
INSERT INTO `stu` VALUES (1,'larry01',1),'larry02',2);
/*!40000 ALTER TABLE `stu` ENABLE KEYS */;
UNLOCK TABLES;
/*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */;
/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
 Dump completed on 2013-09-10 18:56:06
#将输出结果保存到文件中
[root@serv01 databackup]# mysqldump -uroot -p123456 --database larrydb > larrydb.sql

第五步,模拟数据丢失,进入MySQL,删除数据库
MYSQL入门

[root@serv01 data]# mysql -uroot -p123456
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 4
Server version: 5.5.29-log Source distribution
Copyright (c) 2000,2012,Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
mysql> show databases;
+--------------------+
| Database  |
+--------------------+
| information_schema |
| crm  |
| game  |
| hello  |
| larrydb  |
| mnt  |
| mysql  |
| performance_schema |
| test  |
+--------------------+
9 rows in set (0.00 sec)
mysql> drop database larrydb;
Query OK,2 rows affected (0.01 sec)
mysql> show databases;
+--------------------+
| Database  |
+--------------------+
| information_schema |
| crm  |
| game  |
| hello  |
| mnt  |
| mysql  |
| performance_schema |
| test  |
+--------------------+
8 rows in set (0.00 sec)
mysql> exit
Bye

第六步,导入数据
MYSQL入门

[root@serv01 databackup]# mysql -uroot -p123456 <larrydb.sql

?
第七步,登录MySQL,查看数据是否正常
MYSQL入门

[root@serv01 data]# mysql -uroot -p123456
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 6
Server version: 5.5.29-log Source distribution
Copyright (c) 2000,Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
mysql> show database;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'database' at line 1
mysql> show databases;
+--------------------+
| Database  |
+--------------------+
| information_schema |
| crm  |
| game  |
| hello  |
| larrydb  |
| mnt  |
| mysql  |
| performance_schema |
| test  |
+--------------------+
9 rows in set (0.00 sec)
mysql> use larrydb;
Database changed
mysql> select * from class;
+------+--------+
| cid | cname |
+------+--------+
| 1 | linux |
| 2 | oracle |
+------+--------+
2 rows in set (0.00 sec)
mysql> select * from stu;
+------+---------+------+
| sid | sname | cid |
+------+---------+------+
| 1 | larry01 | 1 |
| 2 | larry02 | 2 |
+------+---------+------+
2 rows in set (0.00 sec)

对多个库进行备份
第一步,查看有哪些数据库
MYSQL入门

mysql> show databases;
+--------------------+
| Database  |
+--------------------+
| information_schema |
| crm  |
| game  |
| hello  |
| larrydb  |
| mnt  |
| mysql  |
| performance_schema |
| test  |
+--------------------+
9 rows in set (0.00 sec)
mysql> use game;
Database changed
mysql> show tables;
+----------------+
| Tables_in_game |
+----------------+
| country |
| fight  |
| hero  |
+----------------+
3 rows in set (0.00 sec)
mysql> select * from country;
+-----+---------+----------+
| cno | cname | location |
+-----+---------+----------+
| 10 | caowei | luoyang |
| 20 | shuhan | chengdou |
| 30 | sunwu | nanjing |
| 40 | houhan | luoyang |
| 50 | beisong | kaifeng |
| 60 | 魏国 | 洛阳 |
+-----+---------+----------+
6 rows in set (0.00 sec)

第二步,备份多个库
MYSQL入门

[root@serv01 databackup]# mysqldump -uroot -p123456 --databases larrydb game > larrydb_game.sql
[root@serv01 databackup]# ll larrydb_game.sql 
-rw-r--r--. 1 root root 6159 Sep 10 19:05 larrydb_game.sql

第三步,模拟数据丢失.
MYSQL入门

mysql> drop database game;
Query OK,3 rows affected (0.01 sec)
mysql> drop database larrydb;
Query OK,2 rows affected (0.00 sec)
mysql> use crm;
Database changed
mysql> show tables;
+---------------+
| Tables_in_crm |
+---------------+
| test  |
+---------------+
1 row in set (0.00 sec)
mysql> select * from test;
Empty set (0.00 sec)
mysql> drop database crm;
Query OK,1 row affected (0.00 sec)

第四步,恢复数据
MYSQL入门

[root@serv01 databackup]# mysql -uroot -p123456 < larrydb_game.sql

?
第五步,查看数据是否正常
MYSQL入门

[root@serv01 data]# mysql -uroot -p123456
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 9
Server version: 5.5.29-log Source distribution
Copyright (c) 2000,Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
mysql> show databases;
+--------------------+
| Database  |
+--------------------+
| information_schema |
| game  |
| hello  |
| larrydb  |
| mnt  |
| mysql  |
| performance_schema |
| test  |
+--------------------+
8 rows in set (0.00 sec)
mysql> use game;
Database changed
mysql> select * from country;
+-----+---------+----------+
| cno | cname | location |
+-----+---------+----------+
| 10 | caowei | luoyang |
| 20 | shuhan | chengdou |
| 30 | sunwu | nanjing |
| 40 | houhan | luoyang |
| 50 | beisong | kaifeng |
| 60 | 魏国 | 洛阳 |
+-----+---------+----------+
6 rows in set (0.00 sec)
mysql> use larrydb;
Database changed
mysql> select * from class;
+------+--------+
| cid | cname |
+------+--------+
| 1 | linux |
| 2 | oracle |
+------+--------+
2 rows in set (0.00 sec)

?
备份所有的库
MYSQL入门

[root@serv01 databackup]# mysqldump --help | grep all-database
OR mysqldump [OPTIONS] --all-databases [OPTIONS]
 -A,--all-databases Dump all the databases. This will be same as --databases
   --databases= or --all-databases),the logs will be
   --all-databases or --databases is given.
all-databases   FALSE
[root@serv01 databackup]# mysqldump -uroot -p123456 --all-databases > all_databases.sql
[root@serv01 databackup]# ll all_databases.sql -h
-rw-r--r--. 1 root root 506K Sep 10 19:16 all_databases.sql

备份某张表或者某几张表
第一步,备份某张表和某几张表MYSQL入门

[root@serv01 databackup]# mysqldump game hero country -uroot -p123456 > game_hero_country.sql
[root@serv01 databackup]# ll game_hero_country.sql 
-rw-r--r―. 1 root root 3955 Sep 10 19:11 game_hero_country.sql

第二步,模拟数据丢失
MYSQL入门

mysql> use game;
Database changed
mysql> show tables;
+----------------+
| Tables_in_game |
+----------------+
| country |
| fight  |
| hero  |
+----------------+
3 rows in set (0.00 sec)
mysql> drop table hero;
Query OK,0 rows affected (0.00 sec)
mysql> drop table country;
Query OK,0 rows affected (0.00 sec)

第三步,查看数据是否正常
MYSQL入门

[root@serv01 databackup]# mysql -uroot -p123456 < game_hero_country.sql 
ERROR 1046 (3D000) at line 22: No database selected
[root@serv01 databackup]# mysql -uroot -p123456 --database game < game_hero_country.sql 
[root@serv01 databackup]# mysql -uroot -p123456 -e "select * from game.country"
+-----+---------+----------+
| cno | cname | location |
+-----+---------+----------+
| 10 | caowei | luoyang |
| 20 | shuhan | chengdou |
| 30 | sunwu | nanjing |
| 40 | houhan | luoyang |
| 50 | beisong | kaifeng |
| 60 | 魏国 | 洛阳 |
+-----+---------+----------+

通过这两天关于MySQL热备和冷备的学习,大家是不是对MySQL备份与恢复的了解更加深入了,不管是冷备还是热备其目的都是一致的保证数据的完整性和一致性,备份重于一切!!!
MYSQL入门

相信今天所学的知识在之后的学习工作中对大家有所帮助.MYSQL入门

（编辑：李大同）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!
    相关内容
      推荐文章
        站长推荐
        热点阅读

          【免责声明】本站内容转载自互联网，其发布内容言论不代表本站观点，如果其链接、内容的侵犯您的权益，烦请提交相关链接至邮箱bqsm@foxmail.com我们将及时予以处理。

          建议您使用1920×1080分辨率、谷歌浏览器Google Chrome、Microsoft Edge以获得本站的最佳浏览效果

          Copygight © 2008-2022 https://www.lidatong.com.cn/ All Rights Reserved. 李大同