MySQL中binlog日志文件的详细介绍

使用 binlog2sql 闪回

binlog2sql，作者为曹单锋，大众点评 DBA。binlog2sql，从 MySQL binlog 解析出你要的 SQL。根据不同选项，你可以得到原始 SQL、回滚 SQL、去除主键的 INSERT SQL 等。binlog2sql，底层实现依赖 python-mysql-replication，由该库完成 MySQL 复制协议和 binlog 格式的解析。

$ python binlog2sql/binlog2sql.py -h192.168.2.107 -uroot -p123456 --start-position=154 --stop-position=957 --start-file='mysql-bin.000002'
UPDATE `testdb`.`hello` SET `id`=3, `name`='David' WHERE `id`=3 AND `name`='Will' LIMIT 1; #start 4 end 411 time 2018-06-17 22:54:13
INSERT INTO `testdb`.`hello`(`id`, `name`) VALUES (4, 'Frank'); #start 442 end 684 time 2018-06-17 22:55:47
DELETE FROM `testdb`.`hello` WHERE `id`=2 AND `name`='Bill' LIMIT 1; #start 715 end 956 time 2018-06-17 22:56:44

生成回滚 sql：

$ python binlog2sql/binlog2sql.py --flashback -h192.168.2.107 -uroot -p123456 --start-position=154 --stop-position=956 --start-file='mysql-bin.000002'
INSERT INTO `testdb`.`hello`(`id`, `name`) VALUES (2, 'Bill'); #start 715 end 956 time 2018-06-17 22:56:44
DELETE FROM `testdb`.`hello` WHERE `id`=4 AND `name`='Frank' LIMIT 1; #start 442 end 684 time 2018-06-17 22:55:47
UPDATE `testdb`.`hello` SET `id`=3, `name`='Will' WHERE `id`=3 AND `name`='David' LIMIT 1; #start 154 end 411 time 2018-06-17 22:54:13

闪回的现实原理很简单，先通过 MySQL 复制协议的 com-binlog-dump 命令 dump 出 binlog，然后按照 binlog 的格式规范解析 binlog，将 binlog 转换成 SQL，再将这些 SQL 转换反向逻辑的 SQL，最后再倒序执行。

Java 解析 binlog

上文中的 binlog2sql 其实底层依赖 python-mysql-replication 库，这是 Python 库。如果想使用 Java 解析 binlog 可以使用 mysql-binlog-connector-java（github）库。目前开源的 CDC 工具，如 Zendesk maxwell、Redhat debezium、LinkedIn Databus 等都底层依赖 mysql-binlog-connector-java 或者其前身 open-replicator。使用 mysql-binlog-connector-java 的示例代码如下：

BinaryLogClient client = new BinaryLogClient("192.168.2.107", 3306, "root", "123456");
client.setBinlogFilename("mysql-bin.000001");
client.setBinlogPosition(4);
client.setBlocking(false);
client.registerEventListener(event -> {
    System.out.println(event);
});
client.connect();

输出（省略部分内容）：

...
Event{header=EventHeaderV4{timestamp=1529247253000, eventType=TABLE_MAP, serverId=1, headerLength=19, dataLength=34, nextPosition=346, flags=0}, data=TableMapEventData{tableId=110, database='testdb', table='hello', columnTypes=8, 15, columnMetadata=0, 40, columnNullability={1}}}
Event{header=EventHeaderV4{timestamp=1529247253000, eventType=EXT_UPDATE_ROWS, serverId=1, headerLength=19, dataLength=46, nextPosition=411, flags=0}, data=UpdateRowsEventData{tableId=110, includedColumnsBeforeUpdate={0, 1}, includedColumns={0, 1}, rows=[
    {before=[3, Will], after=[3, David]}
]}}
...
Event{header=EventHeaderV4{timestamp=1529247347000, eventType=TABLE_MAP, serverId=1, headerLength=19, dataLength=34, nextPosition=634, flags=0}, data=TableMapEventData{tableId=110, database='testdb', table='hello', columnTypes=8, 15, columnMetadata=0, 40, columnNullability={1}}}
Event{header=EventHeaderV4{timestamp=1529247347000, eventType=EXT_WRITE_ROWS, serverId=1, headerLength=19, dataLength=31, nextPosition=684, flags=0}, data=WriteRowsEventData{tableId=110, includedColumns={0, 1}, rows=[
    [4, Frank]
]}}
...
Event{header=EventHeaderV4{timestamp=1529247404000, eventType=TABLE_MAP, serverId=1, headerLength=19, dataLength=34, nextPosition=907, flags=0}, data=TableMapEventData{tableId=110, database='testdb', table='hello', columnTypes=8, 15, columnMetadata=0, 40, columnNullability={1}}}
Event{header=EventHeaderV4{timestamp=1529247404000, eventType=EXT_DELETE_ROWS, serverId=1, headerLength=19, dataLength=30, nextPosition=956, flags=0}, data=DeleteRowsEventData{tableId=110, includedColumns={0, 1}, rows=[
    [2, Bill]
]}}

以上就是MySQL中binlog日志文件的详细介绍的详细内容，更多请关注php中文网其它相关文章！

……