MySQL的二进制日志（binlog）使用分析（3）——使用show binlog events命令查看日志信息

技术2025-04-19 24

MySQL的二进制日志（binlog）使用分析（3）——使用show binlog events命令查看日志信息

binlog文件中存储的内容称之为二进制事件，简称事件。我们的每一个数据库更新操作(Insert、Update、Delete等)，都会对应的一个事件。使用show binlog events命令可以以列表的形式显示日志中的事件信息。

一、show binlog events命令的格式

show binlog events [IN 'log_name'] [FROM pos] [LIMIT [offset,] row_count];

说明：（1）IN ‘log_name’：指定要查询的binlog文件名（如果省略此参数，则默认指定第一个binlog文件）；（2）FROM pos：指定从哪个pos起始点开始查起（如果省略此参数，则从整个文件的第一个pos点开始算）；（3）LIMIT【offset】：偏移量（默认为0）；（4）row_count：查询总条数（如果省略，则显示所有行）。

1、查看binlog文件信息

2、查询第一个binlog日志

mysql> show binlog events; +------------------+-----+----------------+-----------+-------------+---------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+----------------+-----------+-------------+---------------------------------------+ | mysql-bin.000001 | 4 | Format_desc | 1 | 123 | Server ver: 5.7.27-log, Binlog ver: 4 | | mysql-bin.000001 | 123 | Previous_gtids | 1 | 154 | | | mysql-bin.000001 | 154 | Anonymous_Gtid | 1 | 219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 219 | Query | 1 | 291 | BEGIN | | mysql-bin.000001 | 291 | Table_map | 1 | 339 | table_id: 113 (hist.t2) | | mysql-bin.000001 | 339 | Write_rows | 1 | 413 | table_id: 113 flags: STMT_END_F | | mysql-bin.000001 | 413 | Xid | 1 | 444 | COMMIT /* xid=16 */ | | mysql-bin.000001 | 444 | Anonymous_Gtid | 1 | 509 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 509 | Query | 1 | 581 | BEGIN | | mysql-bin.000001 | 581 | Table_map | 1 | 629 | table_id: 113 (hist.t2) | | mysql-bin.000001 | 629 | Update_rows | 1 | 845 | table_id: 113 flags: STMT_END_F | | mysql-bin.000001 | 845 | Xid | 1 | 876 | COMMIT /* xid=17 */ | | mysql-bin.000001 | 876 | Rotate | 1 | 923 | mysql-bin.000002;pos=4 | +------------------+-----+----------------+-----------+-------------+---------------------------------------+ 13 rows in set (0.00 sec)

3、查询第二个binlog日志

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 | 1 | 123 | Server ver: 5.7.27-log, Binlog ver: 4 | | mysql-bin.000002 | 123 | Previous_gtids | 1 | 154 | | | mysql-bin.000002 | 154 | Anonymous_Gtid | 1 | 219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000002 | 219 | Query | 1 | 291 | BEGIN | | mysql-bin.000002 | 291 | Table_map | 1 | 336 | table_id: 112 (hist.t1) | | mysql-bin.000002 | 336 | Write_rows | 1 | 386 | table_id: 112 flags: STMT_END_F | | mysql-bin.000002 | 386 | Xid | 1 | 417 | COMMIT /* xid=39 */ | | mysql-bin.000002 | 417 | Anonymous_Gtid | 1 | 482 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000002 | 482 | Query | 1 | 554 | BEGIN | | mysql-bin.000002 | 554 | Table_map | 1 | 599 | table_id: 112 (hist.t1) | | mysql-bin.000002 | 599 | Write_rows | 1 | 649 | table_id: 112 flags: STMT_END_F | | mysql-bin.000002 | 649 | Xid | 1 | 680 | COMMIT /* xid=40 */ | +------------------+-----+----------------+-----------+-------------+---------------------------------------+ 12 rows in set (0.00 sec)

4、查询mysql-bin.000002文件，从pos点417开始查询

mysql> show binlog events in 'mysql-bin.000002' from 417; +------------------+-----+----------------+-----------+-------------+--------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+----------------+-----------+-------------+--------------------------------------+ | mysql-bin.000002 | 417 | Anonymous_Gtid | 1 | 482 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000002 | 482 | Query | 1 | 554 | BEGIN | | mysql-bin.000002 | 554 | Table_map | 1 | 599 | table_id: 112 (hist.t1) | | mysql-bin.000002 | 599 | Write_rows | 1 | 649 | table_id: 112 flags: STMT_END_F | | mysql-bin.000002 | 649 | Xid | 1 | 680 | COMMIT /* xid=40 */ | +------------------+-----+----------------+-----------+-------------+--------------------------------------+ 5 rows in set (0.00 sec)

5、查询mysql-bin.000002文件，从pos点219开始查询，查询5条记录

mysql> show binlog events in 'mysql-bin.000002' from 219 limit 5; +------------------+-----+----------------+-----------+-------------+--------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+----------------+-----------+-------------+--------------------------------------+ | mysql-bin.000002 | 219 | Query | 1 | 291 | BEGIN | | mysql-bin.000002 | 291 | Table_map | 1 | 336 | table_id: 112 (hist.t1) | | mysql-bin.000002 | 336 | Write_rows | 1 | 386 | table_id: 112 flags: STMT_END_F | | mysql-bin.000002 | 386 | Xid | 1 | 417 | COMMIT /* xid=39 */ | | mysql-bin.000002 | 417 | Anonymous_Gtid | 1 | 482 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | +------------------+-----+----------------+-----------+-------------+--------------------------------------+ 5 rows in set (0.00 sec)

6、查询mysql-bin.000002文件，从pos点219开始查询，查询5条记录，偏移2行

mysql> show binlog events in 'mysql-bin.000002' from 219 limit 2,5; +------------------+-----+----------------+-----------+-------------+--------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+----------------+-----------+-------------+--------------------------------------+ | mysql-bin.000002 | 336 | Write_rows | 1 | 386 | table_id: 112 flags: STMT_END_F | | mysql-bin.000002 | 386 | Xid | 1 | 417 | COMMIT /* xid=39 */ | | mysql-bin.000002 | 417 | Anonymous_Gtid | 1 | 482 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000002 | 482 | Query | 1 | 554 | BEGIN | | mysql-bin.000002 | 554 | Table_map | 1 | 599 | table_id: 112 (hist.t1) | +------------------+-----+----------------+-----------+-------------+--------------------------------------+ 5 rows in set (0.00 sec)

二、binlog管理事件

使用show binlog events命令查询到的每一行数据就是一个binlog管理事件。当使用mysqlbinlog查看日志信息时，每两个【at 数字】之间的信息就对应一个管理事件。

mysql> show binlog events in '/var/lib/mysql/mysql-bin.000002'; +------------------+-----+----------------+-----------+-------------+---------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+-----+----------------+-----------+-------------+---------------------------------------+ | mysql-bin.000002 | 4 | Format_desc | 2 | 123 | Server ver: 5.7.27-log, Binlog ver: 4 | | mysql-bin.000002 | 123 | Previous_gtids | 2 | 154 | | | mysql-bin.000002 | 154 | Anonymous_Gtid | 2 | 219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000002 | 219 | Query | 2 | 298 | BEGIN | | mysql-bin.000002 | 298 | Query | 2 | 397 | use `hist`; update t2 set id=id+10000 | | mysql-bin.000002 | 397 | Xid | 2 | 428 | COMMIT /* xid=11 */ | +------------------+-----+----------------+-----------+-------------+---------------------------------------+ 6 rows in set (0.00 sec)

1、每一个管理事件对应的信息说明

（1）Log_name：当前事件所在的binlog文件名称；（2）Pos：当前事件的开始位置，每个事件都占用固定的字节大小，结束位置(End_log_position)减去Pos，就是这个事件占用的字节数。第一个事件位置并不是从0开始，而是从4。Mysql通过文件中的前4个字节，来判断这是不是一个binlog文件。这种方式很常见，很多格式的文件，如pdf、doc、jpg等，都会通常前几个特定字符判断是否是合法文件。（3）Event_type：表示事件的类型；（4）Server_id：表示产生这个事件的mysql server_id，通过设置my.cnf中的server-id选项进行配置；（5）End_log_position：下一个事件的开始位置；（6）Info：当前事件的描述信息。

2、Statement模式下的事件说明

以下是一个Statement日志格式的管理事件信息：

mysql> show binlog events in '/var/lib/mysql/mysql-bin.000001'; +------------------+------+----------------+-----------+-------------+-----------------------------------------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+------+----------------+-----------+-------------+-----------------------------------------------------------------------------+ | mysql-bin.000001 | 4 | Format_desc | 2 | 123 | Server ver: 5.7.27-log, Binlog ver: 4 | | mysql-bin.000001 | 123 | Previous_gtids | 2 | 154 | | | mysql-bin.000001 | 154 | Anonymous_Gtid | 2 | 219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 219 | Query | 2 | 298 | BEGIN | | mysql-bin.000001 | 298 | Intvar | 2 | 330 | INSERT_ID=2 | | mysql-bin.000001 | 330 | Query | 2 | 456 | use `hist`; insert into t2(name) values('zhang'),('wang'),('li') | | mysql-bin.000001 | 456 | Xid | 2 | 487 | COMMIT /* xid=31 */ | | mysql-bin.000001 | 487 | Anonymous_Gtid | 2 | 552 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 552 | Query | 2 | 631 | BEGIN | | mysql-bin.000001 | 631 | Intvar | 2 | 663 | INSERT_ID=5 | | mysql-bin.000001 | 663 | Query | 2 | 789 | use `hist`; insert into t2(name) values('jack'),('tom'),('rose') | | mysql-bin.000001 | 789 | Xid | 2 | 820 | COMMIT /* xid=32 */ | | mysql-bin.000001 | 820 | Anonymous_Gtid | 2 | 885 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 885 | Query | 2 | 964 | BEGIN | | mysql-bin.000001 | 964 | Query | 2 | 1063 | use `hist`; update t2 set id=id+10000 | | mysql-bin.000001 | 1063 | Xid | 2 | 1094 | COMMIT /* xid=33 */ | | mysql-bin.000001 | 1094 | Anonymous_Gtid | 2 | 1159 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 1159 | Query | 2 | 1250 | create database wgx | | mysql-bin.000001 | 1250 | Anonymous_Gtid | 2 | 1315 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 1315 | Query | 2 | 1451 | use `wgx`; create table t1(id int primary key auto_increment,name char(20)) | | mysql-bin.000001 | 1451 | Anonymous_Gtid | 2 | 1516 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000001 | 1516 | Query | 2 | 1593 | BEGIN | | mysql-bin.000001 | 1593 | Intvar | 2 | 1625 | INSERT_ID=1 | | mysql-bin.000001 | 1625 | Query | 2 | 1741 | use `wgx`; insert into t1(name) values('zhang'),('tom') | | mysql-bin.000001 | 1741 | Xid | 2 | 1772 | COMMIT /* xid=44 */ | | mysql-bin.000001 | 1772 | Stop | 2 | 1795 | | +------------------+------+----------------+-----------+-------------+-----------------------------------------------------------------------------+ 26 rows in set (0.01 sec)

说明：

（1）每个binlog文件总是以Format Description Event作为开始，以Rotate Event（Stop Event）作为结束。在开始和结束之间，穿插着其他各种事件。

（2）每个事务都是以Query Event作为开始，其INFO列内容为BEGIN，以Xid Event表示结束，其INFO列内容为COMMIT。即使对于单条更新SQL我们没有开启事务，Mysql也会默认的帮我们开启事务。

（3）Intvar Event事件：如果主键是自增（AUTO_INCREMENT）列，MySQL首先会自增一个值，这就是Intvar Event的作用。需要注意的是，该事件，只会在Statement模式下出现。

（4）Query Event：记录的就是插入的SQL。这也体现了Statement模式的作用，就是记录执行的SQL。

（5）Stop Event：表示日志文件的结束。

2、Row模式下的事件说明

以下是一个Row日志格式的管理事件信息：

说明：

（1）每个binlog文件总是以Format Description Event作为开始，以Rotate Event（Stop Event）作为结束。在开始和结束之间，穿插着其他各种事件。

（2）TABLE_MAP EVENT：其作用是记录INSERT、DELETE、UPDATE操作的表结构。

（3）Write_rows：插入记录。

（4）Update_rows：更新记录。

（5）Rotate Event：表示日志文件的结束。

三、binlog日志的优化

1、binlog_row_image参数

在ROW模式下，即使我们只更新了一条记录的其中某个字段，也会记录每个字段变更前后的值，binlog日志就会变大，带来磁盘IO上的开销，以及网络开销。这个行为可以通过binlog_row_image参数控制，该参数的取值如下： FULL（默认值）：记录列的所有修改，即使字段没有发生变更也会记录。 MINIMAL：只记录修改的列。 NOBLOB：如果是text类型或clob字段，不记录这些日志。

（1）binlog_row_image参数为FULL的binlog日志信息

[root@Mysql11 ~]# mysqlbinlog -v /var/lib/mysql/mysql-bin.000004 /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/; ............. '/*!*/; ### UPDATE `hist`.`stu` ### WHERE ### @1=3 ### @2='jack' ### @3=20 ### @4='Zhengzhou' ### @5='13675871454' ### @6=1 ### SET ### @1=3 ### @2='jack' ### @3=21 ### @4='Zhengzhou' ### @5='13675871454' ### @6=1 # at 464 #200704 11:04:54 server id 1 end_log_pos 495 CRC32 0xc311dbb6 Xid = 18 COMMIT/*!*/; 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*/;

（2）binlog_row_image参数为MINIMAL的binlog日志信息

[root@Mysql11 ~]# mysqlbinlog -v /var/lib/mysql/mysql-bin.000007 /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/; .............. '/*!*/; ### UPDATE `hist`.`stu` ### WHERE ### @1=1 ### SET ### @3=21 # at 394 #200704 11:14:45 server id 1 end_log_pos 425 CRC32 0x54f07b19 Xid = 17 COMMIT/*!*/; 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*/;

3、在Row模式下记录sql语句

在Statement模式下，直接记录SQL比较直观。在Row模式下，使用binlog_rows_query_log_events参数也可以记录SQL。参数的默认为值为FALSE，如果为true的情况下，会通过Rows Query Event来记录SQL。

在my.cnf中添加以下配置，来开启row模式下的SQL记录：

binlog-rows-query-log_events=1

结果如下：

mysql> show binlog events in '/var/lib/mysql/mysql-bin.000009'; +------------------+------+----------------+-----------+-------------+-------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------+------+----------------+-----------+-------------+-------------------------------------------+ | mysql-bin.000009 | 4 | Format_desc | 1 | 123 | Server ver: 5.7.27-log, Binlog ver: 4 | | mysql-bin.000009 | 123 | Previous_gtids | 1 | 154 | | | mysql-bin.000009 | 154 | Anonymous_Gtid | 1 | 219 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000009 | 219 | Query | 1 | 291 | BEGIN | | mysql-bin.000009 | 291 | Rows_query | 1 | 354 | # insert into t2(name) values('zhangfei') | | mysql-bin.000009 | 354 | Table_map | 1 | 402 | table_id: 113 (hist.t2) | | mysql-bin.000009 | 402 | Write_rows | 1 | 451 | table_id: 113 flags: STMT_END_F | | mysql-bin.000009 | 451 | Xid | 1 | 482 | COMMIT /* xid=17 */ | | mysql-bin.000009 | 482 | Anonymous_Gtid | 1 | 547 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000009 | 547 | Query | 1 | 619 | BEGIN | | mysql-bin.000009 | 619 | Rows_query | 1 | 666 | # update t2 set id=id+100 | | mysql-bin.000009 | 666 | Table_map | 1 | 714 | table_id: 113 (hist.t2) | | mysql-bin.000009 | 714 | Update_rows | 1 | 850 | table_id: 113 flags: STMT_END_F | | mysql-bin.000009 | 850 | Xid | 1 | 881 | COMMIT /* xid=18 */ | | mysql-bin.000009 | 881 | Anonymous_Gtid | 1 | 946 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | mysql-bin.000009 | 946 | Query | 1 | 1018 | BEGIN | | mysql-bin.000009 | 1018 | Rows_query | 1 | 1069 | # delete from t2 where id=201 | | mysql-bin.000009 | 1069 | Table_map | 1 | 1117 | table_id: 113 (hist.t2) | | mysql-bin.000009 | 1117 | Delete_rows | 1 | 1157 | table_id: 113 flags: STMT_END_F | | mysql-bin.000009 | 1157 | Xid | 1 | 1188 | COMMIT /* xid=34 */ | +------------------+------+----------------+-----------+-------------+-------------------------------------------+ 20 rows in set (0.00 sec)

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