mysqlbinlog恢复bin-log数据
Binlog日志即binary log，是二进制日志文件，有两个作用，一个是增量备份，另一个是主从复制，即从节点同步主节点数据时获取的即是bin-log，也可以通过bin-log日志来进行本机数据恢复。
1、可以登录mysql客户端查看bin-log有没有开启：
mysql> show variables like '%log_bin%'; +---------------------------------+--------------------------------+ | Variable_name | Value | +---------------------------------+--------------------------------+ | log_bin | ON | | log_bin_basename | /var/lib/mysql/mysql-bin | | log_bin_index | /var/lib/mysql/mysql-bin.index | | log_bin_trust_function_creators | OFF | | log_bin_use_v1_row_events | OFF | | sql_log_bin | ON | +---------------------------------+--------------------------------+ 6 rows in set (0.02 sec)
log_bin为ON时，binlog即开启，为OFF，未开启。以上已开启
2、开启mysql binlog日志：
进入mysql主配置文件(vim /etc/my.cnf)，在mysqld模块下增加以下参数
server-id = 1(单个节点id) log-bin= /var/lib/mysql/mysql-bin(位置一般和mysql库文件所在位置一样) expire_logs_days = 10(表示此日志保存时间为10天；在mysql 8的版本中已经不建议使用此参数)
3、binlog日志包括两类文件；第一个是二进制索引文件(后缀为.index)，第二个为日志文件(后缀名称为.0000*)，记录所有的DML(除SELECT)及DDL语句事件
[root@TestCentos7 ~]# ls /var/lib/mysql/ mysql-bin.000001 mysql-bin.000002 mysql-bin.index mysql.sock
4、查看binlog日志列表：show master logs;
mysql> show master logs; +------------------+-----------+-----------+ | Log_name | File_size | Encrypted | +------------------+-----------+-----------+ | mysql-bin.000001 | 2412 | No | | mysql-bin.000002 | 445 | No | +------------------+-----------+-----------+ 2 rows in set (0.00 sec)
5、查看最后一个binlog日志的编号名称及其最后一个操作事件pos结束点的值：show master status;
mysql> show master status; +------------------+----------+--------------+------------------+----------------------------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set | +------------------+----------+--------------+------------------+----------------------------------------+ | mysql-bin.000002 | 445 | | | c9fba9e2-db3b-11eb-81d4-000c298d8da1:1 | +------------------+----------+--------------+------------------+----------------------------------------+ 1 row in set (0.00 sec)
注意：如果mysql没有开启GTID的话，不会有pos结束点的值，可以使用 show variables like '%gtid_mode%'; 检查是否开启。
6、flush logs 刷新日志，生成一个新编号的binlog文件：
mysql> flush logs; Query OK, 0 rows affected (0.00 sec) mysql> show master logs; +------------------+-----------+-----------+ | Log_name | File_size | Encrypted | +------------------+-----------+-----------+ | mysql-bin.000001 | 2412 | No | | mysql-bin.000002 | 492 | No | | mysql-bin.000003 | 195 | No | +------------------+-----------+-----------+ 3 rows in set (0.00 sec)
每当mysqld服务重启后，会自动刷新binlog文件，mysqldump数据时也可以加-F选项来刷新binlog日志文件
7、清空所有binlog日志文件用 reset master;
8、查看binlog文件内容，使用查看工具mysqlbinlog来查看(vi/vim/cat等都打不开)
# mysqlbinlog mysql-bin.000002 | more
BEGIN /*!*/; # at 309 #201123 14:16:09 server id 100 end_log_pos 369 CRC32 0x73d92352 Table_map: `vfan`.`student` mapped to number 86 # at 369 #201123 14:16:09 server id 100 end_log_pos 414 CRC32 0x0e056855 Write_rows: table id 86 flags: STMT_END_F BINLOG ' qVO7XxNkAAAAPAAAAHEBAAAAAFYAAAAAAAEABHZmYW4AB3N0dWRlbnQAAwMPAQI8AAABAYACASFS I9lz qVO7Xx5kAAAALQAAAJ4BAAAAAFYAAAAAAAEAAgAD/wAFAAAAA0hlZxNVaAUO '/*!*/; # at 414 #201123 14:16:09 server id 100 end_log_pos 445 CRC32 0xfaf4f9c6 Xid = 10 COMMIT/*!*/; # at 445 #201123 14:19:20 server id 100 end_log_pos 492 CRC32 0x95a77234 Rotate to mysql-bin.000003 pos: 4
14:16:09 —— 时间
server id 100 —— server id(my.cnf中设置的id)
end_log_pos 492 —— 结束的Pos点
9、上边的方法内容比较多，也不太容易观察，以下命令更方便查看：show binlog events in 'mysql-bin.000002';
mysql> show binlog events in 'mysql-bin.000002'; +------------------+-----+----------------+-----------+-------------+-------------------------------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+----------------+-----------+-------------+-------------------------------------------------------------------+ | mysql-bin.000002 | 4 | Format_desc | 100 | 124 | Server ver: 8.0.16, Binlog ver: 4 | | mysql-bin.000002 | 124 | Previous_gtids | 100 | 155 | | | mysql-bin.000002 | 155 | Gtid | 100 | 234 | SET @@SESSION.GTID_NEXT= 'c9fba9e2-db3b-11eb-81d4-000c298d8da1:1' | | mysql-bin.000002 | 234 | Query | 100 | 309 | BEGIN | | mysql-bin.000002 | 309 | Table_map | 100 | 369 | table_id: 86 (vfan.student) | | mysql-bin.000002 | 369 | Write_rows | 100 | 414 | table_id: 86 flags: STMT_END_F | | mysql-bin.000002 | 414 | Xid | 100 | 445 | COMMIT /* xid=10 */ | | mysql-bin.000002 | 445 | Rotate | 100 | 492 | mysql-bin.000003;pos=4 | +------------------+-----+----------------+-----------+-------------+-------------------------------------------------------------------+ 8 rows in set (0.00 sec)
10、指定查询
（1）从Pos点414开始查询，如下：
mysql> show binlog events in 'mysql-bin.000002' from 414; +------------------+-----+------------+-----------+-------------+------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+------------+-----------+-------------+------------------------+ | mysql-bin.000002 | 414 | Xid | 100 | 445 | COMMIT /* xid=10 */ | | mysql-bin.000002 | 445 | Rotate | 100 | 492 | mysql-bin.000003;pos=4 | +------------------+-----+------------+-----------+-------------+------------------------+ 2 rows in set (0.00 sec)
（2）从Pos点155开始查询，跳过中间两行，查询后4条数据
mysql> show binlog events in 'mysql-bin.000002' from 155 limit 2,4; +------------------+-----+------------+-----------+-------------+--------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+------------+-----------+-------------+--------------------------------+ | mysql-bin.000002 | 309 | Table_map | 100 | 369 | table_id: 86 (vfan.student) | | mysql-bin.000002 | 369 | Write_rows | 100 | 414 | table_id: 86 flags: STMT_END_F | | mysql-bin.000002 | 414 | Xid | 100 | 445 | COMMIT /* xid=10 */ | | mysql-bin.000002 | 445 | Rotate | 100 | 492 | mysql-bin.000003;pos=4 | +------------------+-----+------------+-----------+-------------+--------------------------------+
（3）从Pos点155开始查询后四行
mysql> show binlog events in 'mysql-bin.000002' from 155 limit 4; +------------------+-----+------------+-----------+-------------+-------------------------------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+------------+-----------+-------------+-------------------------------------------------------------------+ | mysql-bin.000002 | 155 | Gtid | 100 | 234 | SET @@SESSION.GTID_NEXT= 'c9fba9e2-db3b-11eb-81d4-000c298d8da1:1' | | mysql-bin.000002 | 234 | Query | 100 | 309 | BEGIN | | mysql-bin.000002 | 309 | Table_map | 100 | 369 | table_id: 86 (vfan.student) | | mysql-bin.000002 | 369 | Write_rows | 100 | 414 | table_id: 86 flags: STMT_END_F | +------------------+-----+------------+-----------+-------------+-------------------------------------------------------------------+ 4 rows in set (0.00 sec)
11、利用bin-log日志恢复mysql数据，现在有一张表student如下：
mysql> select * from student; +----+------+-----+ | id | name | age | +----+------+-----+ | 1 | Tony | 18 | | 2 | Any | 17 | | 3 | Goy | 20 | | 4 | Baly | 18 | | 5 | Heg | 19 | +----+------+-----+ 5 rows in set (0.00 sec)
（1）先模拟全量备份，进行mysqldump备份
[root@TestCentos7 data]# mysqldump -uroot -proot1 vfan > dump1.sql
（2）由于业务需要，需要对此表进行插入(6 和 7)
mysql> select * from student; +----+------+-----+ | id | name | age | +----+------+-----+ | 1 | Tony | 18 | | 2 | Any | 17 | | 3 | Goy | 20 | | 4 | Baly | 18 | | 5 | Heg | 19 | | 6 | Mom | 20 | | 7 | Lei | 21 | +----+------+-----+ 7 rows in set (0.00 sec)
（3）由于业务需要，要将id=3的name更改为Giil
mysql> UPDATE student set name='Giil' where id=3; Query OK, 1 row affected (0.00 sec) Rows matched: 1 Changed: 1 Warnings: 0 mysql> select * from student; +----+------+-----+ | id | name | age | +----+------+-----+ | 1 | Tony | 18 | | 2 | Any | 17 | | 3 | Giil | 20 | | 4 | Baly | 18 | | 5 | Heg | 19 | | 6 | Mom | 20 | | 7 | Lei | 21 | +----+------+-----+ 7 rows in set (0.01 sec)
（4）操作失误，勿将 vfan 数据库删除
mysql> drop database vfan;
Query OK, 1 row affected (0.10 sec)
（5）先进行全量恢复一下：
mysql> CREATE DATABASE vfan; mysql> use vfan Database changed mysql> source /data/dump1.sql mysql> select * from student; +----+------+-----+ | id | name | age | +----+------+-----+ | 1 | Tony | 18 | | 2 | Any | 17 | | 3 | Goy | 20 | | 4 | Baly | 18 | | 5 | Heg | 19 | +----+------+-----+ 5 rows in set (0.00 sec)
然后通过binlog进行增量恢复，先flush logs;一下，防止再有操作写进此binlog日志中，会增加恢复难度：
mysql> flush logs; Query OK, 0 rows affected (0.01 sec) mysql> show master logs; +------------------+-----------+-----------+ | Log_name | File_size | Encrypted | +------------------+-----------+-----------+ | mysql-bin.000001 | 2412 | No | | mysql-bin.000002 | 492 | No | | mysql-bin.000003 | 1219 | No | | mysql-bin.000004 | 195 | No | +------------------+-----------+-----------+ 4 rows in set (0.00 sec)
查看mysql-bin.000003的具体信息，如下：
INSERT操作：事务的起始Pos点为274，事务提交结束点为495
UPDATE操作：事务的起始Pos点为574，事务提交结束点为886
（6）开始恢复INSERT的数据，执行：
mysqlbinlog --start-position=274 --stop-position=495 --database=vfan /var/lib/mysql/mysql-bin.000003 | mysql -uroot -proot1 -v vfan
此命令意思为mysqlbinlog读取binlog日志内容并通过管道符传给mysql命令，-v表示执行此mysql命令
我执行后有一个报错，大概是GTID_MODE的参数错误：
# mysqlbinlog --start-position=274 --stop-position=495 --database=vfan /var/lib/mysql/mysql-bin.000003 | /mysql -uroot -proot1 -v vfan ERROR 1782 (HY000) at line 23: @@SESSION.GTID_NEXT cannot be set to ANONYMOUS when @@GLOBAL.GTID_MODE = ON.
只需将gtid_mode设置为OFF_PERMISSIVE即可
mysql> set global gtid_mode='on_permissive'; Query OK, 0 rows affected (0.01 sec) mysql> set global gtid_mode='off_permissive'; Query OK, 0 rows affected (0.12 sec) mysql> show variables like '%gtid_mode%'; +---------------+----------------+ | Variable_name | Value | +---------------+----------------+ | gtid_mode | OFF_PERMISSIVE | +---------------+----------------+ 1 row in set (0.00 sec)
再重新执行以上mysqlbinlog命令，执行成功！
再次查看student表内数据：
mysql> select * from student ; +----+------+-----+ | id | name | age | +----+------+-----+ | 1 | Tony | 18 | | 2 | Any | 17 | | 3 | Goy | 20 | | 4 | Baly | 18 | | 5 | Heg | 19 | | 6 | Mom | 20 | | 7 | Lei | 21 | +----+------+-----+ 7 rows in set (0.00 sec)
INSERT操作的数据已经恢复
（7）开始恢复UPDATE的数据
/usr/local/mysql/bin/mysqlbinlog --start-position=574 --stop-position=886 --database=vfan /var/lib/mysql/mysql-bin.000003 | /usr/local/mysql/bin/mysql -uroot -proot1 -v vfan
再次查看，UPDATE的数据也已经恢复：
mysql> select * from student ; +----+------+-----+ | id | name | age | +----+------+-----+ | 1 | Tony | 18 | | 2 | Any | 17 | | 3 | Giil | 20 | | 4 | Baly | 18 | | 5 | Heg | 19 | | 6 | Mom | 20 | | 7 | Lei | 21 | +----+------+-----+ 7 rows in set (0.00 sec)
12、还有另一种可以通过时间来进行恢复：
还是将数据库误删，然后全量恢复完毕，准备增量恢复。
mysql> select * from student; +----+------+-----+ | id | name | age | +----+------+-----+ | 1 | Tony | 18 | | 2 | Any | 17 | | 3 | Goy | 20 | | 4 | Baly | 18 | | 5 | Heg | 19 | +----+------+-----+ 5 rows in set (0.00 sec)
（1）先使用mysqlbinlog查看操作时间
mysqlbinlog mysql-bin.000003 | more
（2）开始恢复，直接将INSERT和UPDATE数据一并恢复
mysqlbinlog --start-datetime="2020-11-23 14:44:18" --stop-datetime="2020-11-23 14:46:28" --database=vfan /var/lib/mysql/mysql-bin.000003 | mysql -uroot -proot1 -v vfan