binlog日志
查询：
MariaDB [(none)]> show variables like 'log_bin';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| log_bin | OFF |
+---------------+-------+
1 row in set (0.00 sec)
MariaDB [(none)]> show variables like 'binlog_format';
+---------------+-----------+
| Variable_name | Value |
+---------------+-----------+
| binlog_format | STATEMENT |
+---------------+-----------+
1 row in set (0.01 sec)
设置：
log_bin/data/mysql/mysql-bin
binlog_format=row
详细：
[mysqld]
basedir=/application/mysql
datadir=/application/mysql/data
socket=/tmp/mysql.sock
log-error=/var/log/mysql.log
log-bin=/data/mysql/mysql-bin
server-id=1
port=3306
log_bin=/data/mysql/mysql-bin
binlog_format=row
[client]
socket=/tmp/mysql.sock
设置完成后检查：
mysql> show variables like 'log_bin';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| log_bin | ON | <------ binlog日志开启
+---------------+-------+
1 row in set (0.00 sec)
mysql> show variables like 'binlog_format';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| binlog_format | ROW | <------ binlog日志开启
+---------------+-------+
1 row in set (0.00 sec)
mysql> show binary logs;
+------------------+-----------+
| Log_name | File_size |
+------------------+-----------+
| mysql-bin.000001 | 177 |
| mysql-bin.000002 | 177 |
| mysql-bin.000003 | 97002 |
| mysql-bin.000004 | 97002 |
| mysql-bin.000005 | 97002 |
| mysql-bin.000006 | 143 |
| mysql-bin.000007 | 120 |
+------------------+-----------+
7 rows in set (0.01 sec)
binlog开启后，可以通过命令查看到哪些日志是正在使用的
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 120 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
#这里的日志 只有一个是在被使用的
查看一个binlog日志详情：
mysql> show binlog events in 'mysql-bin.000004' limit 5;
+------------------+-----+----------------+-----------+-------------+---------------------------------------+
| Log_name | Pos | Event_type | Server_id | End_log_pos | Info |
+------------------+-----+----------------+-----------+-------------+---------------------------------------+
| mysql-bin.000004 | 4 | Format_desc | 6 | 123 | Server ver: 5.7.20-log, Binlog ver: 4 |
| mysql-bin.000004 | 123 | Previous_gtids | 6 | 154 | |
| mysql-bin.000004 | 154 | Anonymous_Gtid | 6 | 219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' |
| mysql-bin.000004 | 219 | Query | 6 | 317 | CREATE DATABASE mysql; |
| mysql-bin.000004 | 317 | Anonymous_Gtid | 6 | 382 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' |
+------------------+-----+----------------+-----------+-------------+---------------------------------------+
5 rows in set (0.00 sec)
这是查看这个binlog日志的前五个事件。
记住： 在binlog最小的记录单元叫event，一个事务会被拆分为多个event。
event特性： 每个event都有一个开始位置[start-position]和一个结束位置[stop-position]
所谓的位置就是： event对于整个二进制文件的相对位置
在一个二进制日志中，前120个 position是文件格式信息的预留空间
也就是mysql第一个记录的时间，都是从120开始的
--row模式下的二进制日志分析案例：
1. 查看日志量
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 120 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
2. 查看日志量
mysql> create database binlog;
Query OK, 1 row affected (0.00 sec)
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 220 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec) ## 说并已经记录了二进制日志了
再添加数据：
mysql> use binlog;
Database changed
mysql> create table bt(id int);
Query OK, 0 rows affected (0.01 sec)
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 321 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
插入一个ddl内容：
mysql> insert into bt values(1);
Query OK, 1 row affected (0.00 sec)
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 513 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
[自动提交，如果没有变化可以使用 commit 提交一次]
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 705 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
主要命令：
mysql> show master status;
mysql> create database binlog;
mysql> show master status;
mysql> use binlog;
#更新数据
mysql> update bt set id=2 where id=2;
Query OK, 0 rows affected (0.00 sec)
Rows matched: 0 Changed: 0 Warnings: 0
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 1862 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
此时感觉错了，想恢复到delete之前的操作发现不会，所以我果断直接删了：
mysql> select * from bt;
+------+
| id |
+------+
| 1 |
+------+
1 row in set (0.00 sec)
mysql> drop table bt;
Query OK, 0 rows affected (0.00 sec)
此时通过binlog查看数据：
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 1981 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
此时。。连库也直接删了：
mysql> drop database binlog;
Query OK, 0 rows affected (0.01 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
| world |
+--------------------+
5 rows in set (0.00 sec)
这时候，整个binlog库都被删除了。
此时来了个大神需要恢复数据：
此时需要用二进制日志进行恢复
恢复思路：
二进制日志是以时间进记录的.
1. 通过show master status; 查看到记录的日志文件。
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000007 | 2070 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
2. 查看这个日志：
mysql> show binlog events in 'mysql-bin.000007';
+------------------+------+-------------+-----------+-------------+---------------------------------------------------------+
| Log_name | Pos | Event_type | Server_id | End_log_pos | Info |
+------------------+------+-------------+-----------+-------------+---------------------------------------------------------+
| mysql-bin.000007 | 4 | Format_desc | 1 | 120 | Server ver: 5.6.38-log, Binlog ver: 4 |
| mysql-bin.000007 | 120 | Query | 1 | 220 | create database binlog |
| mysql-bin.000007 | 220 | Query | 1 | 321 | use `binlog`; create table bt(id int) |
| mysql-bin.000007 | 321 | Query | 1 | 395 | BEGIN |
| mysql-bin.000007 | 395 | Table_map | 1 | 442 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 442 | Write_rows | 1 | 482 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 482 | Xid | 1 | 513 | COMMIT /* xid=46 */ |
| mysql-bin.000007 | 513 | Query | 1 | 587 | BEGIN |
| mysql-bin.000007 | 587 | Table_map | 1 | 634 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 634 | Write_rows | 1 | 674 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 674 | Xid | 1 | 705 | COMMIT /* xid=48 */ |
| mysql-bin.000007 | 705 | Query | 1 | 779 | BEGIN |
| mysql-bin.000007 | 779 | Table_map | 1 | 826 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 826 | Write_rows | 1 | 866 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 866 | Xid | 1 | 897 | COMMIT /* xid=79 */ |
| mysql-bin.000007 | 897 | Query | 1 | 971 | BEGIN |
| mysql-bin.000007 | 971 | Table_map | 1 | 1018 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 1018 | Write_rows | 1 | 1058 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 1058 | Xid | 1 | 1089 | COMMIT /* xid=81 */ |
| mysql-bin.000007 | 1089 | Query | 1 | 1163 | BEGIN |
| mysql-bin.000007 | 1163 | Table_map | 1 | 1210 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 1210 | Write_rows | 1 | 1250 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 1250 | Xid | 1 | 1281 | COMMIT /* xid=87 */ |
| mysql-bin.000007 | 1281 | Query | 1 | 1355 | BEGIN |
| mysql-bin.000007 | 1355 | Table_map | 1 | 1402 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 1402 | Delete_rows | 1 | 1442 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 1442 | Xid | 1 | 1473 | COMMIT /* xid=89 */ |
| mysql-bin.000007 | 1473 | Query | 1 | 1547 | BEGIN |
| mysql-bin.000007 | 1547 | Table_map | 1 | 1594 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 1594 | Delete_rows | 1 | 1634 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 1634 | Xid | 1 | 1665 | COMMIT /* xid=91 */ |
| mysql-bin.000007 | 1665 | Query | 1 | 1739 | BEGIN |
| mysql-bin.000007 | 1739 | Table_map | 1 | 1786 | table_id: 70 (binlog.bt) |
| mysql-bin.000007 | 1786 | Delete_rows | 1 | 1831 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000007 | 1831 | Xid | 1 | 1862 | COMMIT /* xid=93 */ |
| mysql-bin.000007 | 1862 | Query | 1 | 1981 | use `binlog`; DROP TABLE `bt` /* generated by server */ |
| mysql-bin.000007 | 1981 | Query | 1 | 2070 | drop database binlog |
+------------------+------+-------------+-----------+-------------+---------------------------------------------------------+
37 rows in set (0.00 sec)
发现binlog也记录了删除数据的操作。但是又很多看不懂，此时需要使用binlog的专门工具进行查看
查看：
mysqlbinlog --base64-output=decode-rows -vvv /data/mysql/mysql-bin.000007
截取删除之前的日志：
mysqlbinlog --start-position=120 --stop-position=1402 /data/mysql/mysql-bin.000007 >bin.sql
在数据库中暂时关闭日志记录：
mysql> set sql_log_bin=0;
Query OK, 0 rows affected (0.01 sec)
开始恢复数据：
mysql> source /root/bin.sql
验证数据：
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| binlog |
| mysql |
| performance_schema |
| test |
| world |
+--------------------+
6 rows in set (0.00 sec)
已经恢复了 被删除的 binlog 数据库
mysql> show tables;
+------------------+
| Tables_in_binlog |
+------------------+
| bt |
+------------------+
1 row in set (0.00 sec)
经过检查 也恢复了被删除的BT表。