【StoneDB】从库如何规避不支持的DML和DDL

2023年5月10日 147点热度 0人点赞 0条评论

（以下情况仅针对StoneDB 1.0版本不支持的部分DML和DDL操作，StoneDB 2.0及以上版本将无需此类操作）
主从复制中，主库的任何更新都会同步到从库，如果从库不想重做主库的某个更新动作，可以使用以下两种方法进行规避。当然，最终带来的影响是主从环境数据不一致的问题。
以下的测试环境中，主库是 InnoDB，从库是 StoneDB，在主库做从库不支持的 DML 或者 DDL。

从库执行 GTID 的空事务

###主库
mysql> show create table ttt\G                             
*************************** 1. row ***************************
       Table: ttt
Create Table: CREATE TABLE `ttt` (
  `id` int(11) NOT NULL,
  `name` varchar(5) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4
1 row in set (0.00 sec)

mysql> select * from ttt;     
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  3 | CCC  |
+----+------+
3 rows in set (0.00 sec)

###从库
mysql> show create table ttt\G
*************************** 1. row ***************************
       Table: ttt
Create Table: CREATE TABLE `ttt` (
  `id` int(11) NOT NULL,
  `name` varchar(5) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=STONEDB DEFAULT CHARSET=utf8mb4
1 row in set (0.02 sec)

mysql> select * from ttt;
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  3 | CCC  |
+----+------+
3 rows in set (0.00 sec)

###主库
mysql> delete from ttt where id=3;
Query OK, 1 row affected (0.00 sec)

mysql> select * from ttt;                
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
+----+------+
2 rows in set (0.00 sec)

###从库
mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.30.101
                  Master_User: u_repl
                  Master_Port: 33306
                Connect_Retry: 60
              Master_Log_File: binlog.000002
          Read_Master_Log_Pos: 1053
               Relay_Log_File: ub01-relay-bin.000002
                Relay_Log_Pos: 993
        Relay_Master_Log_File: binlog.000002
             Slave_IO_Running: Yes
            Slave_SQL_Running: No
              Replicate_Do_DB: 
          Replicate_Ignore_DB: 
           Replicate_Do_Table: 
       Replicate_Ignore_Table: 
      Replicate_Wild_Do_Table: 
  Replicate_Wild_Ignore_Table: 
                   Last_Errno: 1031
                   Last_Error: Error 'Table storage engine for 'ttt' doesn't have this option' on query. Default database: 'db'. Query: 'delete from ttt where id=3'
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 786
              Relay_Log_Space: 1466
              Until_Condition: None
               Until_Log_File: 
                Until_Log_Pos: 0
           Master_SSL_Allowed: No
           Master_SSL_CA_File: 
           Master_SSL_CA_Path: 
              Master_SSL_Cert: 
            Master_SSL_Cipher: 
               Master_SSL_Key: 
        Seconds_Behind_Master: NULL
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error: 
               Last_SQL_Errno: 1031
               Last_SQL_Error: Error 'Table storage engine for 'ttt' doesn't have this option' on query. Default database: 'db'. Query: 'delete from ttt where id=3'
  Replicate_Ignore_Server_Ids: 
             Master_Server_Id: 101
                  Master_UUID: ae40cabd-efb2-11ec-ac20-44a84203989a
             Master_Info_File: /data/stonedb/install/data/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: 
           Master_Retry_Count: 86400
                  Master_Bind: 
      Last_IO_Error_Timestamp: 
     Last_SQL_Error_Timestamp: 220729 02:26:29
               Master_SSL_Crl: 
           Master_SSL_Crlpath: 
           Retrieved_Gtid_Set: ae40cabd-efb2-11ec-ac20-44a84203989a:1-4
            Executed_Gtid_Set: 4ddecc1a-ee49-11ec-96fe-f219e7257407:1,
ae40cabd-efb2-11ec-ac20-44a84203989a:1-3
                Auto_Position: 1
         Replicate_Rewrite_DB: 
                 Channel_Name: 
           Master_TLS_Version: 
1 row in set (0.00 sec)

mysql> select * from ttt;
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  3 | CCC  |
+----+------+
3 rows in set (0.00 sec)

主库执行 delete后，由于 StoneDB 不支持 delete，从库会有报错，并且主从复制中断。
下一步需要在主库找到执行 delete操作的gtid值。

###主库
mysql> show binary logs;
+---------------+-----------+
| Log_name      | File_size |
+---------------+-----------+
| binlog.000001 |       177 |
| binlog.000002 |      1053 |
+---------------+-----------+
2 rows in set (0.00 sec)

mysql> show binlog events in '/data/stonedb/install/binlog/binlog.000002';
+---------------+------+----------------+-----------+-------------+-------------------------------------------------------------------+
| Log_name      | Pos  | Event_type     | Server_id | End_log_pos | Info                                                              |
+---------------+------+----------------+-----------+-------------+-------------------------------------------------------------------+
| binlog.000002 |    4 | Format_desc    |       101 |         123 | Server ver: 5.7.36-StoneDB-log, Binlog ver: 4                     |
| binlog.000002 |  123 | Previous_gtids |       101 |         154 |                                                                   |
| binlog.000002 |  154 | Gtid           |       101 |         219 | SET @@SESSION.GTID_NEXT= 'ae40cabd-efb2-11ec-ac20-44a84203989a:1' |
| binlog.000002 |  219 | Query          |       101 |         307 | create database db                                                |
| binlog.000002 |  307 | Gtid           |       101 |         372 | SET @@SESSION.GTID_NEXT= 'ae40cabd-efb2-11ec-ac20-44a84203989a:2' |
| binlog.000002 |  372 | Query          |       101 |         494 | use `db`; create table ttt(id int primary key,name varchar(5))    |
| binlog.000002 |  494 | Gtid           |       101 |         559 | SET @@SESSION.GTID_NEXT= 'ae40cabd-efb2-11ec-ac20-44a84203989a:3' |
| binlog.000002 |  559 | Query          |       101 |         634 | BEGIN                                                             |
| binlog.000002 |  634 | Query          |       101 |         755 | use `db`; insert into ttt values(1,'AAA'),(2,'BBB'),(3,'CCC')     |
| binlog.000002 |  755 | Xid            |       101 |         786 | COMMIT /* xid=20 */                                               |
| binlog.000002 |  786 | Gtid           |       101 |         851 | SET @@SESSION.GTID_NEXT= 'ae40cabd-efb2-11ec-ac20-44a84203989a:4' |
| binlog.000002 |  851 | Query          |       101 |         926 | BEGIN                                                             |
| binlog.000002 |  926 | Query          |       101 |        1022 | use `db`; delete from ttt where id=3                              |
| binlog.000002 | 1022 | Xid            |       101 |        1053 | COMMIT /* xid=28 */                                               |
+---------------+------+----------------+-----------+-------------+-------------------------------------------------------------------+
14 rows in set (0.00 sec)

如果是在生产环境找主库 delete 操作的 gtid 值，需要知道哪个时间点，然后用 mysqlbinlog 解析binlog。
这里由于是做测试，可以简单快递的找到 delete 操作的 gtid 值，ae40cabd-efb2-11ec-ac20-44a84203989a:4。
gtid 值由参数 server_uuid 和事务 id 组成，标识一个这个操作的唯一性。

###从库
set gtid_next='ae40cabd-efb2-11ec-ac20-44a84203989a:4';
begin;
commit;
set gtid_next=automatic;
start slave;

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.30.101
                  Master_User: u_repl
                  Master_Port: 33306
                Connect_Retry: 60
              Master_Log_File: binlog.000002
          Read_Master_Log_Pos: 1053
               Relay_Log_File: ub01-relay-bin.000002
                Relay_Log_Pos: 1260
        Relay_Master_Log_File: binlog.000002
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB: 
          Replicate_Ignore_DB: 
           Replicate_Do_Table: 
       Replicate_Ignore_Table: 
      Replicate_Wild_Do_Table: 
  Replicate_Wild_Ignore_Table: 
                   Last_Errno: 0
                   Last_Error: 
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 1053
              Relay_Log_Space: 1466
              Until_Condition: None
               Until_Log_File: 
                Until_Log_Pos: 0
           Master_SSL_Allowed: No
           Master_SSL_CA_File: 
           Master_SSL_CA_Path: 
              Master_SSL_Cert: 
            Master_SSL_Cipher: 
               Master_SSL_Key: 
        Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error: 
               Last_SQL_Errno: 0
               Last_SQL_Error: 
  Replicate_Ignore_Server_Ids: 
             Master_Server_Id: 101
                  Master_UUID: ae40cabd-efb2-11ec-ac20-44a84203989a
             Master_Info_File: /data/stonedb/install/data/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
           Master_Retry_Count: 86400
                  Master_Bind: 
      Last_IO_Error_Timestamp: 
     Last_SQL_Error_Timestamp: 
               Master_SSL_Crl: 
           Master_SSL_Crlpath: 
           Retrieved_Gtid_Set: ae40cabd-efb2-11ec-ac20-44a84203989a:1-4
            Executed_Gtid_Set: 4ddecc1a-ee49-11ec-96fe-f219e7257407:1,
ae40cabd-efb2-11ec-ac20-44a84203989a:1-4
                Auto_Position: 1
         Replicate_Rewrite_DB: 
                 Channel_Name: 
           Master_TLS_Version: 
1 row in set (0.00 sec)

mysql> select * from ttt;
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  3 | CCC  |
+----+------+
3 rows in set (0.00 sec)

利用 gtid 跳过一个空事务后，主从复制的线程已经正常启动，但由于 StoneDB 不支持 delete，现在主从环境数据是不一致的。

###主库
mysql> insert into ttt values(4,'DDD');
Query OK, 1 row affected (0.00 sec)

mysql> select * from ttt;
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  4 | DDD  |
+----+------+
3 rows in set (0.00 sec)

###从库
mysql> select * from ttt;
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  3 | CCC  |
|  4 | DDD  |
+----+------+
4 rows in set (0.00 sec)

主从复制的线程启动后，主库的更新，从库同步正常。

如果觉得在主库找 delete 的 gtid 值麻烦，在主库执行 delete 前，可以指定 delete 的 gtid 值。在从库还是根据这个 gtid 值执行空事务。

###
mysql> show variables like 'server_uuid';
+---------------+--------------------------------------+
| Variable_name | Value                                |
+---------------+--------------------------------------+
| server_uuid   | ae40cabd-efb2-11ec-ac20-44a84203989a |
+---------------+--------------------------------------+
1 row in set (0.01 sec)

mysql> set gtid_next='ae40cabd-efb2-11ec-ac20-44a84203989a:100';
Query OK, 0 rows affected (0.00 sec)

mysql> begin;
Query OK, 0 rows affected (0.00 sec)

mysql> delete from ttt where id=1;
Query OK, 1 row affected (0.00 sec)

mysql> commit;
Query OK, 0 rows affected (0.00 sec)

mysql> set gtid_next=automatic;
Query OK, 0 rows affected (0.00 sec)

###从库
set gtid_next='ae40cabd-efb2-11ec-ac20-44a84203989a:100';
begin;
commit;
set gtid_next=automatic;
start slave;

关闭当前线程的binlog

###主库
mysql> show create table ttt\G                                             
*************************** 1. row ***************************
       Table: ttt
Create Table: CREATE TABLE `ttt` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(5) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8mb4
1 row in set (0.00 sec)

mysql> select * from ttt;     
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
+----+------+
2 rows in set (0.00 sec)

###从库
mysql> show create table ttt\G
*************************** 1. row ***************************
       Table: ttt
Create Table: CREATE TABLE `ttt` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(5) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=STONEDB DEFAULT CHARSET=utf8mb4
1 row in set (0.00 sec)

mysql> select * from ttt;
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
+----+------+
2 rows in set (0.00 sec)

###主库
mysql> set sql_log_bin=off;
Query OK, 0 rows affected (0.00 sec)

mysql> alter table ttt modify name varchar(10);
Query OK, 0 rows affected (0.00 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> show create table ttt\G                 
*************************** 1. row ***************************
       Table: ttt
Create Table: CREATE TABLE `ttt` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(10) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8mb4
1 row in set (0.00 sec)

###从库
mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.30.101
                  Master_User: u_repl
                  Master_Port: 33306
                Connect_Retry: 60
              Master_Log_File: binlog.000002
          Read_Master_Log_Pos: 2288
               Relay_Log_File: ub01-relay-bin.000002
                Relay_Log_Pos: 2495
        Relay_Master_Log_File: binlog.000002
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB: 
          Replicate_Ignore_DB: 
           Replicate_Do_Table: 
       Replicate_Ignore_Table: 
      Replicate_Wild_Do_Table: 
  Replicate_Wild_Ignore_Table: 
                   Last_Errno: 0
                   Last_Error: 
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 2288
              Relay_Log_Space: 2701
              Until_Condition: None
               Until_Log_File: 
                Until_Log_Pos: 0
           Master_SSL_Allowed: No
           Master_SSL_CA_File: 
           Master_SSL_CA_Path: 
              Master_SSL_Cert: 
            Master_SSL_Cipher: 
               Master_SSL_Key: 
        Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error: 
               Last_SQL_Errno: 0
               Last_SQL_Error: 
  Replicate_Ignore_Server_Ids: 
             Master_Server_Id: 101
                  Master_UUID: ae40cabd-efb2-11ec-ac20-44a84203989a
             Master_Info_File: /data/stonedb/install/data/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
           Master_Retry_Count: 86400
                  Master_Bind: 
      Last_IO_Error_Timestamp: 
     Last_SQL_Error_Timestamp: 
               Master_SSL_Crl: 
           Master_SSL_Crlpath: 
           Retrieved_Gtid_Set: ae40cabd-efb2-11ec-ac20-44a84203989a:1-8:100
            Executed_Gtid_Set: 4ddecc1a-ee49-11ec-96fe-f219e7257407:1-3,
ae40cabd-efb2-11ec-ac20-44a84203989a:1-8:100
                Auto_Position: 1
         Replicate_Rewrite_DB: 
                 Channel_Name: 
           Master_TLS_Version: 
1 row in set (0.00 sec)

mysql> show create table ttt\G
*************************** 1. row ***************************
       Table: ttt
Create Table: CREATE TABLE `ttt` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(5) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=STONEDB DEFAULT CHARSET=utf8mb4
1 row in set (0.00 sec)

主库关闭当前线程的binlog，对表做DDL,将字段 name 的长度扩大。
主从复制正常，从库表的字段 name 的长度不变。

###主库
开启新的线程，注意一点是开启新的线程！！！
mysql> insert into ttt(name) values('CCC');
Query OK, 1 row affected (0.00 sec)

mysql> select * from ttt;                  
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  3 | CCC  |
+----+------+
3 rows in set (0.00 sec)

###从库
mysql> select * from ttt;
+----+------+
| id | name |
+----+------+
|  1 | AAA  |
|  2 | BBB  |
|  3 | CCC  |
+----+------+
3 rows in set (0.00 sec)

sql_log_bin=off，关闭的是当前线程的binlog，不影响其他线程的任何更新。

以上两种方法都可以规避从库不想重做主库的某个更新动作，目的是让从库遇到不支持的操作时可以让主从复制的线程正常工作，但带来的问题是主从环境数据不一致。