您好,登录后才能下订单哦!
1、简介
row格式的binlog文件中,每个ROW_EVENT之前都有一个TABLE_MAP_EVENT,用于描述表的内部ID和结构定义。
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 */ |
| mysql-bin.000002 | 311 | Query | 11 | 382 | BEGIN |
| mysql-bin.000002 | 382 | Table_map | 11 | 427 | table_id: 70 (yzs.t1) |
| mysql-bin.000002 | 427 | Write_rows | 11 | 471 | table_id: 70 flags: STMT_END_F |
| mysql-bin.000002 | 471 | Xid | 11 | 502 | COMMIT /* xid=37 */ |
+------------------+-----+-------------+-----------+-------------+---------------------------------------------+
9 rows in set (0.00 sec)
2、TABLE_MAP_EVENT格式定义
3、结合案例说明
--------公有事件头-------
1)timestamp:62 ca a4 5a:4个字节
2)event_type:13:1个字节,TABLE_MAP_EVENT = 19
3)server-id:0b 00 00 00,4个字节,即11
4)event_size:2d 00 00 00,4个字节,即event总大小是45字节
5)next-log ps:ec 00 00 00,4个字节,即236
6)flag:00 00
----------私有事件头-------------
7)table ID:46 00 00 00 00 00,即table ID是70
8)flag:01 00,暂时未使用
----------事件体-------------------
9)schema name length:03,即schema name大小是3个字节
10)schema name:79 7a 73,yzs
11)00
12)table name length:02,即表名大小是2个字节
13)table name:74 31,即表名是t1
14)00
15)col count:02,即列个数是2
16)col type:03 03
enum enum_field_types { MYSQL_TYPE_DECIMAL, MYSQL_TYPE_TINY,
MYSQL_TYPE_SHORT, MYSQL_TYPE_LONG,
MYSQL_TYPE_FLOAT, MYSQL_TYPE_DOUBLE,
MYSQL_TYPE_NULL, MYSQL_TYPE_TIMESTAMP,
MYSQL_TYPE_LONGLONG,MYSQL_TYPE_INT24,
MYSQL_TYPE_DATE, MYSQL_TYPE_TIME,
MYSQL_TYPE_DATETIME, MYSQL_TYPE_YEAR,
MYSQL_TYPE_NEWDATE, MYSQL_TYPE_VARCHAR,
MYSQL_TYPE_BIT,
MYSQL_TYPE_TIMESTAMP2,
MYSQL_TYPE_DATETIME2,
MYSQL_TYPE_TIME2,
MYSQL_TYPE_NEWDECIMAL=246,
MYSQL_TYPE_ENUM=247,
MYSQL_TYPE_SET=248,
MYSQL_TYPE_TINY_BLOB=249,
MYSQL_TYPE_MEDIUM_BLOB=250,
MYSQL_TYPE_LONG_BLOB=251,
MYSQL_TYPE_BLOB=252,
MYSQL_TYPE_VAR_STRING=253,
MYSQL_TYPE_STRING=254,
MYSQL_TYPE_GEOMETRY=255
};
17)col meta length:00,1个字节
18)col meta:无
19)null bitmap:02,列数是2,一个字节就够:00000010,即主键列那列不能为NULL
20)checksum,不在事件体里。d8 b9 92 2b
write_footer函数最后会计算checksum,并放到事件体后。
virtual bool write(IO_CACHE* file)
{
return(write_header(file, get_data_size()) ||
write_data_header(file) ||
write_data_body(file) ||
write_footer(file));
}
# at 191
#180310 21:53:38 server id 11 end_log_pos 236 CRC32 0x2b92b9d8 Table_map: `yzs`.`t1` mapped to number 70
可以看到和binlog文件里解析出来的一致。
免责声明:本站发布的内容(图片、视频和文字)以原创、转载和分享为主,文章观点不代表本网站立场,如果涉及侵权请联系站长邮箱:is@yisu.com进行举报,并提供相关证据,一经查实,将立刻删除涉嫌侵权内容。