Parsing MySQL Binlog-(1) Approximate structure and event type

1. Introduction

Binlog records database changes in the form of events. You can view events by executing the show Binlog events in "Binlog file" command

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 |         11 | 120 |  Server ver:5.6.26-debug-log, Binlog ver:4 | | mysql-bin.000002 | 120 |        Query |         11 | 191 |  BEGIN | | mysql-bin.000002 | 191 |        Table_map |         11 | 236 |  Table_id:70 (YZS.T1) | | mysql-bin.000002 | 236 |        Write_rows |         11 | 280 |  Table_id:70 Flags:stmt_end_f | | mysql-bin.000002 | 280 |        Xid |         11 | 311 |  COMMIT/* xid=9 */| +------------------+-----+-------------+-----------+-------------+---------------------------------------------+ 5 rows in Set (0.00 sec)   

Mysql> Show Binlog events in "mysql-bin.000001"; +------------------+-----+-------------+-----------+-------------+--------------------------------------------- +  | Log_name | Pos | Event_type | server_id | End_log_pos |  Info | +------------------+-----+-------------+-----------+-------------+--------------------------------------------- +  |   mysql-bin.000001 | 4 |        Format_desc |         11 | 120 |  Server ver:5.6.26-debug-log, Binlog ver:4 | | mysql-bin.000001 | 120 |        Query |         11 | 197 |  BEGIN | | mysql-bin.000001 | 197 |        Query |         11 | 294 | Use ' Yzs ';  INSERT INTO T1 select 2,2 | | mysql-bin.000001 | 294 |        Xid |         11 | 325 |  COMMIT/* xid=9 */| | mysql-bin.000001 | 325 |        Stop |         11 |                                             348 |  | +------------------+-----+-------------+-----------+-------------+---------------------------------------------+ 5 rows in Set (0.00 sec) 

2. Binlog event format and type

Divided into 2 parts, event headers and event bodies. Event headers include:

Timestamp: The execution time of the start of the event, the fixed 4-byte display is the number of seconds since the epoch time.

Event Type: Indicates the type of the event

Server-id: Server ID for servers

Event Size: The length of the event

Next-log pos: Fixed 4 bytes Start position of next event

Flag: Fixed 2 bytes Event flags
#define LOG_EVENT_BINLOG_IN_USE_F 0x1 This flags indicates whether BINLOG is properly closed.
.. Other tags can be see source log_event.h

Event Body: Different information is included depending on the type of event.

Binlog Event Type:

Only the more important event types are selected for parsing. The following section parses each event type in detail.

Parsing MySQL Binlog-(1) Approximate structure and event type