mysql/mysql-MD/第五章:权限管理及数据备份与恢复.md

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权限管理及数据备份与恢复

作者:行癫(盗版必究)


一:权限管理

1.权限级别

Global level系统级所有库所有表的权限

Database level某个数据库中的所有表的权限

Table level库中的某个表的权限

Column level表中的某个字段的权限

procs level某个存储过程的权限

proxies level代理服务器的权限

2.查看权限记录表

因为超级管理员默认已经设置;所以直接查询权限即可

Global level
 mysql> select * from mysql.user\G
*************************** 1. row ***************************
                  Host: localhost
                  User: root
           Select_priv: Y
           Insert_priv: Y
           Update_priv: Y
           Delete_priv: Y
           Create_priv: Y
             Drop_priv: Y
           Reload_priv: Y
         Shutdown_priv: Y
          Process_priv: Y
             File_priv: Y
            Grant_priv: Y
       References_priv: Y
            Index_priv: Y
            Alter_priv: Y
          Show_db_priv: Y
            Super_priv: Y
 Create_tmp_table_priv: Y
      Lock_tables_priv: Y
          Execute_priv: Y
       Repl_slave_priv: Y
      Repl_client_priv: Y
      Create_view_priv: Y
        Show_view_priv: Y
   Create_routine_priv: Y
    Alter_routine_priv: Y
      Create_user_priv: Y
            Event_priv: Y
          Trigger_priv: Y
Create_tablespace_priv: Y
              ssl_type: 
            ssl_cipher: 
           x509_issuer: 
          x509_subject: 
         max_questions: 0
           max_updates: 0
       max_connections: 0
  max_user_connections: 0
                plugin: mysql_native_password
 authentication_string: *B1DD4ADE47888D9AEC4D705C85230F1B52D2A817
      password_expired: N
 password_last_changed: 2022-09-25 14:44:38
     password_lifetime: NULL
        account_locked: N

字段介绍:

用户字段root
权限字段Select_priv
安全字段:*B1DD4ADE47888D9AEC4D705C85230F1B52D2A817

Select_priv查询权限
Insert_priv插入权限
Update_priv更新权限
Delete_priv删除权限
......
Database level
mysql> select * from mysql.db\G;
*************************** 1. row ***************************
                 Host: localhost
                   Db: performance_schema
                 User: mysql.session
          Select_priv: Y
          Insert_priv: N
          Update_priv: N
          Delete_priv: N
          Create_priv: N
            Drop_priv: N
           Grant_priv: N
      References_priv: N
           Index_priv: N
           Alter_priv: N
Create_tmp_table_priv: N
     Lock_tables_priv: N
     Create_view_priv: N
       Show_view_priv: N
  Create_routine_priv: N
   Alter_routine_priv: N
         Execute_priv: N
           Event_priv: N
         Trigger_priv: N

测试库权限:

mysql> create database t1;
Query OK, 1 row affected (0.00 sec)

mysql> grant all on t1.* to 't1'@'localhost' identified by 'QianFeng@123';
Query OK, 0 rows affected, 1 warning (0.00 sec)

查看:

mysql> select * from mysql.db\G
*************************** 3. row ***************************
                 Host: localhost
                   Db: t1
                 User: t1
          Select_priv: Y
          Insert_priv: Y
          Update_priv: Y
          Delete_priv: Y
          Create_priv: Y
            Drop_priv: Y
           Grant_priv: N
      References_priv: Y
           Index_priv: Y
           Alter_priv: Y
Create_tmp_table_priv: Y
     Lock_tables_priv: Y
     Create_view_priv: Y
       Show_view_priv: Y
  Create_routine_priv: Y
   Alter_routine_priv: Y
         Execute_priv: Y
           Event_priv: Y
         Trigger_priv: Y
3 rows in set (0.00 sec)

验证:

[root@xingdian ~]# mysql -u t1 -pQianFeng@123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.7.39-log MySQL Community Server (GPL)

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

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 |
| t1                 |
+--------------------+
2 rows in set (0.00 sec)

Table level
mysql> select * from mysql.tables_priv\G;
*************************** 1. row ***************************
       Host: localhost
         Db: mysql
       User: mysql.session
 Table_name: user
    Grantor: boot@connecting host
  Timestamp: 0000-00-00 00:00:00
 Table_priv: Select
Column_priv: 
*************************** 2. row ***************************
       Host: localhost
         Db: sys
       User: mysql.sys
 Table_name: sys_config
    Grantor: root@localhost
  Timestamp: 2022-09-25 14:40:58
 Table_priv: Select
Column_priv: 
2 rows in set (0.00 sec)

创建库表验证:

mysql> create database t2;
Query OK, 1 row affected (0.00 sec)

mysql> use t2;
Database changed
mysql> create table u1(id int);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into u1 values (1);
Query OK, 1 row affected (0.01 sec)

mysql> grant all on t2.u1 to 't2'@'localhost' identified by 'QianFeng@123';
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> create table u2(id int);
Query OK, 0 rows affected (0.01 sec)

mysql> show tables;
+--------------+
| Tables_in_t2 |
+--------------+
| u1           |
| u2           |
+--------------+
2 rows in set (0.00 sec)

权限查看:

mysql> select * from mysql.tables_priv\G;
*************************** 3. row ***************************
       Host: localhost
         Db: t2
       User: t2
 Table_name: u1
    Grantor: root@localhost
  Timestamp: 0000-00-00 00:00:00
 Table_priv: Select,Insert,Update,Delete,Create,Drop,References,Index,Alter,Create View,Show view,Trigger
Column_priv: 
3 rows in set (0.00 sec)

验证登录t2账户看到u1表看不到u2代表权限成功

[root@xingdian ~]# mysql -u t2 -pQianFeng@123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.7.39-log MySQL Community Server (GPL)

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

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 |
| t2                 |
+--------------------+
2 rows in set (0.00 sec)

mysql> use t2;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+--------------+
| Tables_in_t2 |
+--------------+
| u1           |
+--------------+
1 row in set (0.00 sec)
Column level
[root@xingdian ~]# mysql -uroot -pQianFeng@123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.7.39-log MySQL Community Server (GPL)

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

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> select * from mysql.columns_priv\G; 
Empty set (0.00 sec)

mysql> insert into mysql.columns_priv(host,db,user,table_name,column_name,column_priv) values('%','t2','t2','u1','id','select');  
Query OK, 1 row affected (0.00 sec)

mysql> select * from mysql.columns_priv\G;
*************************** 1. row ***************************
       Host: %
         Db: t2
       User: t2
 Table_name: u1
Column_name: id
  Timestamp: 2022-09-25 15:34:05
Column_priv: Select
1 row in set (0.00 sec)

注意:

前提是有库,有表,有权限

二:用户管理

1.登录和退出

[root@xingdian ~]# mysql -h 192.168.18.160 -P 30042 -u root -pmysql -e "show databases;"
[root@xingdian ~]# mysql -h 192.168.18.160 -P 30042 -u root -pmysql mysql -e "show tables;"

    -h	指定主机名                       【默认为localhost】
    -P	MySQL服务器端口                  【默认3306】
    -u	指定用户名                       【默认root】
    -p	指定登录密码                     【默认为空密码】
	此处mysql为指定登录的数据库 
    -e	接SQL语句  (在脚本中使用)

2.创建用户

方式一:

mysql> create user xingdian;
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements
注意:
	该报错是因为密码强度问题,取消密码强度即可创建用户

mysql> create user xingdian@'%' identified by 'QianFeng@123';
Query OK, 0 rows affected (0.00 sec)

方式二:

mysql> grant all on *.* to 'diange'@'localhost' identified by 'QianFeng@123';
Query OK, 0 rows affected, 1 warning (0.00 sec)

注意:

该方式采用授权的方式

ALL 所有权限 select 单独某一个权限(多个权限用逗号隔开)

mysql> grant select on *.* to 'dianye'@'localhost' identified by 'QianFeng@123';
Query OK, 0 rows affected, 1 warning (0.00 sec)
*.*		所有的库所有的表   也可以单独某一个库某一个表
xingdian@localhost  用户有则授权无则创建   localhost % 10.19.40.% 10.19.40.11

3.删除用户

方式一:

MySQL [(none)]> Drop user xingdian@'%';
Query OK, 0 rows affected (0.00 sec)

方法二:

MySQL [(none)]> delete from mysql.user where user='diandian' AND Host='%';
Query OK, 1 row affected (0.00 sec)

4.修改密码

方式一:

[root@xingdian ~]# mysqladmin -uroot -p'123' password 'new_password'	    //123为旧密码

方式二:

MySQL [(none)]> update mysql.user set authentication_string=password(123456) where user='diange' And Host='%';

注意:

刷新授权表后生效flush privileges

自己设置自己密码:

MySQL [(none)]> set password='123';
Query OK, 0 rows affected (0.00 sec)

root用户修改其他用户密码

方法一:

mysql> SET PASSWORD FOR user3@'localhost'='new_password';

方法二:

UPDATE mysql.user SET authentication_string=password('new_password') WHERE user='user3' AND host='localhost';

5.查看密码策略

mysql> SHOW VARIABLES LIKE 'validate_password%';
+--------------------------------------+--------+
| Variable_name                        | Value  |
+--------------------------------------+--------+
| validate_password_check_user_name    | OFF    |
| validate_password_dictionary_file    |        |
| validate_password_length             | 8      |
| validate_password_mixed_case_count   | 1      |
| validate_password_number_count       | 1      |
| validate_password_policy             | MEDIUM |
| validate_password_special_char_count | 1      |
+--------------------------------------+--------+
7 rows in set (0.00 sec)

参数解释:

validate_password_dictionary_file 指定密码验证的文件路径

validate_password_length 密码最小长度

validate_password_mixed_case_count 密码至少要包含的小写字母个数和大写字母个数

validate_password_number_count 密码至少要包含的数字个数

validate_password_policy 密码强度检查等级对应等级为0/LOW、1/MEDIUM、2/STRONG,默认为1

0/LOW只检查长度

1/MEDIUM检查长度、数字、大小写、特殊字符

2/STRONG检查长度、数字、大小写、特殊字符字典文件

validate_password_special_char_count密码至少要包含的特殊字符数

修改密码策略:

mysql> SHOW VARIABLES LIKE 'validate_password%';
+--------------------------------------+--------+
| Variable_name                        | Value  |
+--------------------------------------+--------+
| validate_password_check_user_name    | OFF    |
| validate_password_dictionary_file    |        |
| validate_password_length             | 8      |
| validate_password_mixed_case_count   | 1      |
| validate_password_number_count       | 1      |
| validate_password_policy             | MEDIUM |
| validate_password_special_char_count | 1      |
+--------------------------------------+--------+
7 rows in set (0.00 sec)

mysql> set global validate_password_length=4;
Query OK, 0 rows affected (0.00 sec)

mysql> SHOW VARIABLES LIKE 'validate_password%';
+--------------------------------------+--------+
| Variable_name                        | Value  |
+--------------------------------------+--------+
| validate_password_check_user_name    | OFF    |
| validate_password_dictionary_file    |        |
| validate_password_length             | 4      |
| validate_password_mixed_case_count   | 1      |
| validate_password_number_count       | 1      |
| validate_password_policy             | MEDIUM |
| validate_password_special_char_count | 1      |
+--------------------------------------+--------+
7 rows in set (0.00 sec)

关闭密码策略:

修改配置文件,添加以下参数:
validate_password=off

三:数据备份及恢复

1.概述

所有备份数据都应放在非数据库本地,而且建议有多份副本

备份: 能够防止由于机械故障以及人为误操作带来的数据丢失,例如将数据库文件保存在了其它地方

冗余: 数据有多份冗余,但不等备份,只能防止机械故障还来的数据丢失,例如主备模式、数据库集群

备份考虑的因素:

数据的一致性

服务的可用性

分类:

逻辑备份

备份的是建表、建库、插入等操作所执行SQL语句适用于中小型数据库效率相对较低mysqldump

物理备份

直接复制数据库文件适用于大型数据库环境不受存储引擎的限制但不能恢复到不同的MySQL版本tar、xtrabackup

备份方式分类:

完全备份

备份所有数据

增量备份

每次备份上一次备份到现在产生的新数据

image-20220925184632820

差异备份

只备份跟完整备份不一样的

2.tar备份

注意:备份期间,服务不可用

备份过程:完全物理备份

停止数据库

[root@xingdian ~]# systemctl stop mysqld

tar备份数据

[root@xingdian ~]# mkdir /backup
[root@xingdian ~]# cd /var/lib/mysql
[root@xingdian ~]# tar -zcvf /backup/`date +%F`-mysql-all.tar.gz ./*

启动数据库(备份完成后启动数据库,继续为其他服务提供服务)

[root@xingdian ~]# systemctl start mysqld

恢复过程:模拟数据丢失,恢复数据

停止数据库

[root@xingdian ~]# systemctl stop mysqld

清理环境

[root@xingdian ~]# rm -rf /var/lib/mysql/* 

导入备份数据

[root@xingdian ~]# tar -xvf /backup/2019-08-20-mysql-all.tar.gz -C /usr/lib/mysql
[root@xingdian ~]# chown mysql.mysql /var/lib/mysql/* -R

启动数据库(恢复后验证数据是否恢复成功)

[root@xingdian ~]# systemctl start mysqld

3.xtrabackup备份

简介:

percona-xtrabackup是开源免费的支持MySQL 数据库热备份的软件能对InnoDB和XtraDB存储引擎的数据库非阻塞地备份它不暂停服务创建Innodb热备份为mysql做增量备份在mysql服务器之间做在线表迁移使创建replication更加容易备份mysql而不增加服务器的负载

image-20220925185829126

安装软件:

[root@xingdian ~]# yum install https://repo.percona.com/yum/percona-release-latest.noarch.rpm -y
[root@xingdian ~]# yum install percona-xtrabackup-24 -y
完整备份

创建备份目录:

[root@xingdian ~]# mkdir -p /xtrabackup/full/

备份:

[root@xingdian ~]# innobackupex --user=root --password='QianFeng@123' /xtrabackup/full/

查看备份数据:

[root@xingdian ~]# ls /xtrabackup/full/
2022-09-25_19-40-47

模拟数据丢失数据恢复:(以下操作模拟数据丢失)

丢失前数据库中的数据:

[root@xingdian ~]# mysql -u root -pQianFeng@123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.7.39 MySQL Community Server (GPL)

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

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 |
| mysql              |
| performance_schema |
| sys                |
| t1                 |
+--------------------+
5 rows in set (0.00 sec)

数据丢失:

[root@xingdian ~]# systemctl stop mysqld
[root@xingdian ~]# rm -rf /var/lib/mysql/*
[root@xingdian ~]# rm -rf /var/log/mysqld.log 
[root@xingdian ~]# rm -rf /var/log/mysql-slow/slow.log (有则删除,无则不需要操作)

恢复前的验证:

[root@xingdian ~]# innobackupex --apply-log /xtrabackup/full/2022-09-25_19-40-47/

恢复之前需要确认配置文件内有数据库目录指定不然xtrabackup不知道恢复到哪里

[root@xingdian ~]# cat /etc/my.cnf
datadir=/var/lib/mysql

恢复数据:

[root@xingdian ~]# innobackupex --copy-back /xtrabackup/full/2022-09-25_19-40-47/

修改权限:

[root@xingdian ~]# chown  mysql.mysql /var/lib/mysql -R

启动服务:

[root@xingdian ~]# systemctl start mysqld

验证:

[root@xingdian ~]# mysql -u root -pQianFeng@123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.39 MySQL Community Server (GPL)

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

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 |
| mysql              |
| performance_schema |
| sys                |
| t1                 |
+--------------------+
5 rows in set (0.00 sec)
增量备份

原理:每次备份上一次备份到现在产生的新数据

注意:在进行增量备份前先进行完整备份

案例:周一进行全备,周二到周天进行增量备份

完整备份:(周一)

[root@xingdian ~]# innobackupex --user=root --password='QianFeng@123' /xtrabackup/full

创建增量备份存放数据目录:

[root@xingdian ~]# mkdir /xtrabackup/zeng -p

模拟数据增加(略)

第一次增量备份:(周二)

[root@xingdian ~]# innobackupex --user=root --password='QianFeng@123' --incremental /xtrabackup/zeng/ --incremental-basedir=/xtrabackup/full/2022-09-25_19-40-47/

第一次增量备份的数据:
[root@xingdian ~]# ls /xtrabackup/zeng/
2022-09-25_19-56-00

模拟数据增加(略)

第二次增量备份:(周三)

[root@xingdian ~]# innobackupex --user=root --password='QianFeng@123' --incremental /xtrabackup/zeng/ --incremental-basedir=/xtrabackup/zeng/2022-09-25_19-56-00/

第二次增量备份的数据:
[root@xingdian ~]# ls /xtrabackup/zeng/
2022-09-25_19-56-00  2022-09-25_19-58-12

后面的增量备份重复上面的操作(略)

增量备份数据恢复流程:(需要模拟数据的丢失)

停止数据库:

[root@xingdian ~]# systemctl stop mysqld

删除数据:

[root@xingdian ~]# rm -rf /var/lib/mysql/*
[root@xingdian ~]# rm -rf /var/log/mysqld.log

其他数据根据实际情况删除

依次重演回滚:

全备回滚:
[root@xingdian ~]# innobackupex --apply-log --redo-only /xtrabackup/full/2022-09-25_19-40-47/

第一次增量回滚:
[root@xingdian ~]# innobackupex --apply-log --redo-only /xtrabackup/full/2022-09-25_19-40-47/ --incremental-dir=/xtrabackup/zeng/2022-09-25_19-56-00/

第二次增量回滚:
[root@xingdian ~]# innobackupex --apply-log --redo-only /xtrabackup/full/2022-09-25_19-40-47/ --incremental-dir=/xtrabackup/zeng/2022-09-25_19-58-12/

根据实际增量备份的次数回滚,可以想恢复到那个时间节点就回滚到那个时间节点,所有的回滚都给全备

恢复数据:

[root@xingdian ~]# innobackupex --copy-back /xtrabackup/full/2022-09-25_19-40-47/

修改权限:

[root@xingdian ~]# chown mysql.mysql /var/lib/mysql -R

启动数据库:

[root@xingdian ~]# systemctl start mysqld

验证:

[root@xingdian ~]# mysql -u root -pQianFeng@123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.39 MySQL Community Server (GPL)

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

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 |
| mysql              |
| performance_schema |
| sys                |
| t1                 |
| t2                 |
| t3                 |
+--------------------+
差异备份

原理:只备份跟完整备份不一样的

注意:在进行增量备份前先进行完整备份

案例:周一进行全备,周二到周天进行差异备份

完整备份:(周一)

[root@xingdian ~]# mkdir -p /xtrabackup/full
[root@xingdian ~]# innobackupex --user=root --password=QianFeng@123 /xtrabackup/full

模拟数据增加(略)

第一次差异备份:(周二)

[root@xingdian ~]# mkdir -p /xtrabackup/jian
[root@xingdian ~]# innobackupex --user=root --password=QianFeng@123 --incremental /xtrabackup/jian --incremental-basedir=/xtrabackup/full/2022-09-25_20-10-52/

查看第一次差异备份的数据:
[root@xingdian ~]# ls /xtrabackup/jian/
2022-09-25_20-12-55

模拟数据增加(略)

第二次差异备份:(周三)

[root@xingdian ~]# innobackupex --user=root --password=QianFeng@123 --incremental /xtrabackup/jian --incremental-basedir=/xtrabackup/full/2022-09-25_20-10-52/

查看第二次差异备份的数据:
[root@xingdian ~]# ls /xtrabackup/jian/
2022-09-25_20-12-55  2022-09-25_20-14-32

注意:后面的差异备份跟之前一样,根据需求可以继续差异备份

差异备份恢复流程:(模拟数据丢失)

停止数据库:

[root@xingdian ~]# systemctl stop mysqld

删除数据:

[root@xingdian ~]# rm -rf /var/lib/mysql/*
[root@xingdian ~]# rm -rf /var/log/mysqld.log 

重演数据回滚:

完整备份回滚:
[root@xingdian ~]# innobackupex --apply-log --redo-only /xtrabackup/full/2022-09-25_20-10-52/

差异备份回滚(根据差异备份的原理,如果恢复所有数据只需要将最后依次差异回滚)
[root@xingdian ~]# innobackupex --apply-log --redo-only /xtrabackup/full/2022-09-25_20-10-52/ --incremental-dir=/xtrabackup/jian/2022-09-25_20-14-32/

恢复数据:

[root@xingdian ~]#  innobackupex --copy-back /xtrabackup/full/2022-09-25_20-10-52/

修改权限:

[root@xingdian ~]# chown  mysql.mysql /var/lib/mysql -R

启动数据库:

[root@xingdian ~]# systemctl start  mysqld

数据验证:

[root@xingdian ~]# mysql -u root -pQianFeng@123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.39 MySQL Community Server (GPL)

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

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 |
| k1                 |
| k2                 |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
9 rows in set (0.00 sec)

4.mysqldump备份

备份表:(前提有库有表)

[root@xingdian ~]# mysqldump -u root -pQianFeng@123 k1 t1 > /t1.sql

恢复表:(恢复之前模拟数据丢失)

[root@xingdian ~]# mysql -u root -pQianFeng@123 k1 < /t1.sql 
mysql: [Warning] Using a password on the command line interface can be insecure.

验证:

[root@xingdian ~]# mysql -u root -pQianFeng@123 -e "use k1;show tables"
mysql: [Warning] Using a password on the command line interface can be insecure.
+--------------+
| Tables_in_k1 |
+--------------+
| t1           |
+--------------+

备份一个库:

[root@xingdian ~]# mysqldump -u root -pQianFeng@123 k1 > /k1.sql

备份多个库:

[root@xingdian ~]# mysqldump -u root -pQianFeng@123 -B k1 k2 > /kall.sql

备份所有库:

[root@xingdian ~]# mysqldump -u root -pQianFeng@123 -A > /all.sql

数据恢复:

为保证数据一致性,应在恢复数据之前停止数据库对外的服务,停止binlog日志

binlog使用binlog日志恢复数据时也会产生binlog日志如果开启的话需要关闭

mysql> set sql_log_bin=0;
Query OK, 0 rows affected (0.00 sec)

模拟数据丢失(略)

[root@xingdian ~]# mysql -u root -pQianFeng@123 -D k1 < /k1.sql 
mysql: [Warning] Using a password on the command line interface can be insecure.
ERROR 1049 (42000): Unknown database 'k1'
出现该错误是因为在恢复的时候需要有库的存在

[root@xingdian ~]# mysql -u root -pQianFeng@123 -e "create database k1"
[root@xingdian ~]# mysql -u root -pQianFeng@123 -D k1 < /k1.sql 

[root@xingdian ~]# mysql -u root -pQianFeng@123 -e "create database k1"
[root@xingdian ~]# mysql -u root -pQianFeng@123 -e "create database k2"
[root@xingdian ~]# mysql -u root -pQianFeng@123 -D k1 k2 < /kall.sql

或者
mysql> source  /k1.sql

验证:

[root@xingdian ~]# mysql -u root -pQianFeng@123 -e "use k1; show tables;"
mysql: [Warning] Using a password on the command line interface can be insecure.
+--------------+
| Tables_in_k1 |
+--------------+
| t1           |
+--------------+
[root@xingdian ~]# mysql -u root -pQianFeng@123 -e "use k2; show tables;"
mysql: [Warning] Using a password on the command line interface can be insecure.
+--------------+
| Tables_in_k2 |
+--------------+
| t1           |
+--------------+

5.binlog日志备份

原理:日志方法备份恢复数据

日志默认存储位置:

rpm /var/lib/mysql

编译: 安装目录的var下

产生日志:

方式一:编译安装

[root@xingdian ~]# mysqld_safe --log-bin --user=mysql --server-id=1 &

查看binlog日志
[root@xingdian ~]# mysqlbinlog slave2-bin.000001     -v --base64-output=decode-rows
        时间点    141126 14:04:49
        位置点  :     at  106

方式二rpm安装永久

[root@xingdian ~]# vim /etc/my.cnf
log-bin=mylog
server-id=1        //做主从复制使用

[root@xingdian ~]# systemctl restart mysqld

查看:
[root@xingdian ~]# ls /var/lib/mysql
auto.cnf         client-key.pem  ib_logfile1   mysql               private_key.pem  sys
ca-key.pem       ib_buffer_pool  ibtmp1        mysql.sock          public_key.pem   xingdian-bin.index
ca.pem           ibdata1         mylog.000001  mysql.sock.lock     server-cert.pem  xtrabackup_info
client-cert.pem  ib_logfile0     mylog.index

[root@xingdian ~]# mysqlbinlog /var/lib/mysql/mylog.000001 -v --base64-output=decode-rows
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
DELIMITER /*!*/;
# at 4
#220925 21:12:47 server id 1  end_log_pos 123 CRC32 0x52358645  Start: binlog v 4, server v 5.7.39-log created 220925 21:12:47 at startup
# Warning: this binlog is either in use or was not closed properly.
ROLLBACK/*!*/;
# at 123
#220925 21:12:47 server id 1  end_log_pos 154 CRC32 0xa84d8536  Previous-GTIDs
# [empty]
# at 154
#220925 21:13:38 server id 1  end_log_pos 219 CRC32 0xc2b00431  Anonymous_GTID  last_committed=0        sequence_number=1    rbr_only=no
SET @@SESSION.GTID_NEXT= 'ANONYMOUS'/*!*/;
# at 219
#220925 21:13:38 server id 1  end_log_pos 307 CRC32 0x635401a5  Query   thread_id=2     exec_time=0     error_code=0
SET TIMESTAMP=1664111618/*!*/;
SET @@session.pseudo_thread_id=2/*!*/;
SET @@session.foreign_key_checks=1, @@session.sql_auto_is_null=0, @@session.unique_checks=1, @@session.autocommit=1/*!*/;
SET @@session.sql_mode=1436549152/*!*/;
SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/*!*/;
/*!\C utf8 *//*!*/;
SET @@session.character_set_client=33,@@session.collation_connection=33,@@session.collation_server=8/*!*/;
SET @@session.lc_time_names=0/*!*/;
SET @@session.collation_database=DEFAULT/*!*/;
create database t1
/*!*/;
SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/;
DELIMITER ;
# End of log file
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/;

方法二:
mysql>  show binlog events in  "mylog.000001";
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
| Log_name     | Pos | Event_type     | Server_id | End_log_pos | Info                                  |
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
| mylog.000001 |   4 | Format_desc    |         1 |         123 | Server ver: 5.7.39-log, Binlog ver: 4 |
| mylog.000001 | 123 | Previous_gtids |         1 |         154 |                                       |
| mylog.000001 | 154 | Anonymous_Gtid |         1 |         219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS'  |
| mylog.000001 | 219 | Query          |         1 |         307 | create database t1                    |
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
4 rows in set (0.00 sec)

默认查看第一个
mysql>  show binlog events;
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
| Log_name     | Pos | Event_type     | Server_id | End_log_pos | Info                                  |
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
| mylog.000001 |   4 | Format_desc    |         1 |         123 | Server ver: 5.7.39-log, Binlog ver: 4 |
| mylog.000001 | 123 | Previous_gtids |         1 |         154 |                                       |
| mylog.000001 | 154 | Anonymous_Gtid |         1 |         219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS'  |
| mylog.000001 | 219 | Query          |         1 |         307 | create database t1                    |
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
4 rows in set (0.00 sec)

数据恢复:

根据时间点恢复数据:

[root@xingdian ~]# mysqlbinlog --start-datetime='2022-9-25 21:12:47' --stop-datetime='2022-9-25 21:16:55' /var/lib/mysql/mylog.000001  | mysql -u root -pQianFeng@123

根据位置点恢复数据:

mysql>  show binlog events;
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
| Log_name     | Pos | Event_type     | Server_id | End_log_pos | Info                                  |
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
| mylog.000001 |   4 | Format_desc    |         1 |         123 | Server ver: 5.7.39-log, Binlog ver: 4 |
| mylog.000001 | 123 | Previous_gtids |         1 |         154 |                                       |
| mylog.000001 | 154 | Anonymous_Gtid |         1 |         219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS'  |
| mylog.000001 | 219 | Query          |         1 |         307 | create database t1                    |
| mylog.000001 | 307 | Anonymous_Gtid |         1 |         372 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS'  |
| mylog.000001 | 372 | Query          |         1 |         453 | drop database t1                      |
| mylog.000001 | 453 | Anonymous_Gtid |         1 |         518 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS'  |
| mylog.000001 | 518 | Query          |         1 |         606 | create database t1                    |
| mylog.000001 | 606 | Anonymous_Gtid |         1 |         671 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS'  |
| mylog.000001 | 671 | Query          |         1 |         752 | drop database t1                      |
+--------------+-----+----------------+-----------+-------------+---------------------------------------+
[root@xingdian ~]# mysqlbinlog --start-position 219 --stop-position 307 /var/lib/mysql/mylog.000001 | mysql -u root -pQianFeng@123