数据库备份
数据库备份方案：
全量备份
全量备份就是指对某一个时间点上的所有数据或应用进行的一个完全拷贝，
数据恢复快，备份时间长
增量备份
增量备份是指在一次全备份或上一次增量备份后，以后每次的备份只需备份
与前一次相比增加和者被修改的文件。
没有重复的备份数据
备份时间短
恢复数据时必须按一定的顺序进行
差异备份
备份上一次的完全备份后发生变化的所有文件，差异备份是指在一次全备份后到进行差异备份的这段时间内
对那些增加或者修改文件的备份。在进行恢复时，我们只需对第一次全量备份和最后一次差异备份进行恢复。
备份的工具mysqldump
/语法：
mysqldump [OPTIONS] database [tables ...]
mysqldump [OPTIONS] --all-databases [OPTIONS]
mysqldump [OPTIONS] --databases [OPTIONS] DB1 [DB2 DB3...]
//常用的OPTIONS：
-uUSERNAME //指定数据库用户名
-hHOST //指定服务器主机，请使用ip地址
-pPASSWORD //指定数据库用户的密码
-P# //指定数据库监听的端口，这里的#需用实际的端口号代替，如-P3307
1.全量备份
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
+--------------------+
5 rows in set (0.01 sec)
mysql> use test;
Database changed
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| name |
| run |
+----------------+
2 rows in set (0.00 sec)
#备份所有数据库
[root@localhost ~]# mysqldump -uroot -p --all-databases > all-$(date +%F-%T).mysql
Enter password:
#备份test数据库name表
[root@localhost ~]# mysqldump -uroot -p test name > table-$(date +%F-%T).mysql
Enter password:
#备份test数据库
[root@localhost ~]# mysqldump -uroot -p --databases test > DBtest-$(date +%F-%T).mysql
Enter password:
[root@localhost ~]# ls
all-2020-12-29-22:53:34.mysql DBtest-2020-12-29-22:59:41.mysql table-2020-12-29-22:57:34.mysql table-2020-12-29-22:58:33.mysql
数据库恢复
#误删test数据库
mysql> drop database test;
Query OK, 2 rows affected (0.01 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.00 sec)
#恢复test数据库
[root@localhost ~]# mysql -uroot -p < DBtest-2020-12-29-22\:59\:41.mysql
Enter password:
[root@localhost ~]# mysql -uroot -p -e 'show databases;'
Enter password:
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
+--------------------+
2.差异备份
开启MySQL服务器的二进制日志功能
[root@localhost ~]# vim /etc/my.cnf
[mysqld]
basedir = /usr/local/mysql
datadir = /opt/data
socket = /tmp/mysql.sock
port = 3306
pid-file = /opt/data/mysql.pid
user = mysql
skip-name-resolve
server-id=1 #设置服务器标识符
log-bin=mysql_bin #开启二进制日志功能
#重启服务
[root@localhost ~]# service mysqld restart
Shutting down MySQL.. SUCCESS!
Starting MySQL. SUCCESS!
对数据库进行完全备份
mysql> show databases ;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| test |
+--------------------+
3 rows in set (0.01 sec)
mysql> use test;
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_test |
+----------------+
| name |
| run |
+----------------+
2 rows in set (0.00 sec)
mysql> select * from name;
+----+---------+------+
| id | name | age |
+----+---------+------+
| 1 | tom | 18 |
| 2 | jerry | 19 |
| 3 | battle | 20 |
| 4 | between | 21 |
+----+---------+------+
4 rows in set (0.00 sec)
mysql> select * from run;
+----+----------+------+
| id | name | age |
+----+----------+------+
| 1 | xiaoming | 20 |
| 2 | huahua | 22 |
| 3 | yechui | 25 |
+----+----------+------+
3 rows in set (0.00 sec)
#全量备份数据库
[root@localhost ~]# mysqldump -uroot -p --single-transaction --flush-logs --master-data=2 --all-databases --delete-master-logs > all-$(date +%F-%T).sql
Enter password:
[root@localhost ~]# ls
all-2020-12-30-09:38:40.sql
#新增内容
mysql> insert run(name,age) values('xx',12),('cc',18);
Query OK, 2 rows affected (0.00 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select * from run;
+----+----------+------+
| id | name | age |
+----+----------+------+
| 1 | xiaoming | 20 |
| 2 | huahua | 22 |
| 3 | yechui | 25 |
| 4 | xx | 12 |
| 5 | cc | 18 |
+----+----------+------+
5 rows in set (0.00 sec)
误删test数据库
[root@localhost ~]#
[root@localhost ~]# mysql -uroot -p -e 'drop database test;'
Enter password:
[root@localhost ~]# mysql -uroot -p -e 'show databases;'
Enter password:
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
差异备份的恢复
刷新创建新的二进制日志
[root@localhost ~]# ll /opt/data/
total 123128
-rw-r-----. 1 mysql mysql 56 Dec 28 18:44 auto.cnf
-rw-------. 1 mysql mysql 1676 Dec 28 18:44 ca-key.pem
-rw-r--r--. 1 mysql mysql 1112 Dec 28 18:44 ca.pem
-rw-r--r--. 1 mysql mysql 1112 Dec 28 18:44 client-cert.pem
-rw-------. 1 mysql mysql 1676 Dec 28 18:44 client-key.pem
-rw-r-----. 1 mysql mysql 963 Dec 30 09:37 ib_buffer_pool
-rw-r-----. 1 mysql mysql 12582912 Dec 30 09:54 ibdata1
-rw-r-----. 1 mysql mysql 50331648 Dec 30 09:54 ib_logfile0
-rw-r-----. 1 mysql mysql 50331648 Dec 28 18:44 ib_logfile1
-rw-r-----. 1 mysql mysql 12582912 Dec 30 09:38 ibtmp1
-rw-r-----. 1 mysql mysql 163944 Dec 30 09:37 localhost.localdomain.err
drwxr-x---. 2 mysql mysql 4096 Dec 30 09:37 mysql
-rw-r-----. 1 mysql mysql 582 Dec 30 09:52 mysql_bin.000010
-rw-r-----. 1 mysql mysql 19 Dec 30 09:38 mysql_bin.index
-rw-r-----. 1 mysql mysql 5 Dec 30 09:37 mysql.pid
-rw-r--r--. 1 root root 6 Dec 30 09:37 mysql_upgrade_info
drwxr-x---. 2 mysql mysql 8192 Dec 30 09:37 performance_schema
-rw-------. 1 mysql mysql 1676 Dec 28 18:44 private_key.pem
-rw-r--r--. 1 mysql mysql 452 Dec 28 18:44 public_key.pem
-rw-r--r--. 1 mysql mysql 1112 Dec 28 18:44 server-cert.pem
-rw-------. 1 mysql mysql 1680 Dec 28 18:44 server-key.pem
drwxr-x---. 2 mysql mysql 8192 Dec 30 09:37 sys
[root@localhost ~]# mysqladmin -uroot -p flush-logs #刷新创建新的二进制文件
Enter password:
[root@localhost ~]# ll /opt/data/
total 123132
-rw-r-----. 1 mysql mysql 56 Dec 28 18:44 auto.cnf
-rw-------. 1 mysql mysql 1676 Dec 28 18:44 ca-key.pem
-rw-r--r--. 1 mysql mysql 1112 Dec 28 18:44 ca.pem
-rw-r--r--. 1 mysql mysql 1112 Dec 28 18:44 client-cert.pem
-rw-------. 1 mysql mysql 1676 Dec 28 18:44 client-key.pem
-rw-r-----. 1 mysql mysql 963 Dec 30 09:37 ib_buffer_pool
-rw-r-----. 1 mysql mysql 12582912 Dec 30 09:54 ibdata1
-rw-r-----. 1 mysql mysql 50331648 Dec 30 09:54 ib_logfile0
-rw-r-----. 1 mysql mysql 50331648 Dec 28 18:44 ib_logfile1
-rw-r-----. 1 mysql mysql 12582912 Dec 30 09:38 ibtmp1
-rw-r-----. 1 mysql mysql 163944 Dec 30 09:37 localhost.localdomain.err
drwxr-x---. 2 mysql mysql 4096 Dec 30 09:37 mysql
-rw-r-----. 1 mysql mysql 629 Dec 30 09:55 mysql_bin.000010
-rw-r-----. 1 mysql mysql 154 Dec 30 09:55 mysql_bin.000011
恢复完全备份
[root@localhost ~]# mysql -uroot -p < all-2020-12-30-09\:38\:40.sql
Enter password:
[root@localhost ~]# mysql -uroot -p -e 'show databases;'
Enter password:
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
+--------------------+
[root@localhost ~]# mysql -uroot -p -e 'select * from test.run;'
Enter password:
+----+----------+------+
| id | name | age |
+----+----------+------+
| 1 | xiaoming | 20 |
| 2 | huahua | 22 |
| 3 | yechui | 25 |
+----+----------+------+
[root@localhost ~]#
恢复差异备份
#j检查误删时数据库在什么位置
mysql> show binlog events in 'mysql_bin.000010';
+------------------+-----+----------------+-----------+-------------+---------------------------------------+
| Log_name | Pos | Event_type | Server_id | End_log_pos | Info |
+------------------+-----+----------------+-----------+-------------+---------------------------------------+
| mysql_bin.000010 | 4 | Format_desc | 1 | 123 | Server ver: 5.7.31-log, Binlog ver: 4 |
| mysql_bin.000010 | 123 | Previous_gtids | 1 | 154 | |
| mysql_bin.000010 | 154 | Anonymous_Gtid | 1 | 219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' |
| mysql_bin.000010 | 219 | Query | 1 | 291 | BEGIN |
| mysql_bin.000010 | 291 | Table_map | 1 | 341 | table_id: 175 (test.run) |
| mysql_bin.000010 | 341 | Write_rows | 1 | 394 | table_id: 175 flags: STMT_END_F |
| mysql_bin.000010 | 394 | Xid | 1 | 425 | COMMIT /* xid=956 */ |
| mysql_bin.000010 | 425 | Anonymous_Gtid | 1 | 490 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' |
| mysql_bin.000010 | 490 | Query | 1 | 582 | drop database test |
| mysql_bin.000010 | 582 | Rotate | 1 | 629 | mysql_bin.000011;pos=4 |
+------------------+-----+----------------+-----------+-------------+---------------------------------------+
10 rows in set (0.00 sec)
#使用mysqlbinlog恢复差异备份
Bye
[root@localhost ~]# mysqlbinlog --stop-position=490 /opt/data/mysql_bin.000010 | mysql -uroot -p
Enter password:
[root@localhost ~]# mysql -uroot -p -e 'select * from test.run;'
Enter password:
+----+----------+------+
| id | name | age |
+----+----------+------+
| 1 | xiaoming | 20 |
| 2 | huahua | 22 |
| 3 | yechui | 25 |
| 4 | xx | 12 |
| 5 | cc | 18 |
+----+----------+------+
报错：mysqldump: Couldn't execute 'SHOW VARIABLES LIKE 'gtid\_mode'': Table 'performance_schema.session_variables' doesn't exist (1146)
解决办法：mysql_upgrade -u root -p --force #更新
service mysqld restart #重启服务
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