1.演示实验环境
--主库版本：
root@(none)>show variables like 'version';
+---------------+---------------------+
| Variable_name | Value |
+---------------+---------------------+
| version | 5.7.23-23-31.31-log |
+---------------+---------------------+
1 row in set (0.01 sec)
--复制模式
root@(none)>show variables like '%gtid_mode%';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| gtid_mode | ON |
+---------------+-------+
1 row in set (0.00 sec)
--复制进程
root@(none)>show processlist;
+----+-----------------+---------------------+-------+------------------+-------+---------------------------------------------------------------+------------------+-----------+---------------+
| Id | User | Host | db | Command | Time | State | Info | Rows_sent | Rows_examined |
+----+-----------------+---------------------+-------+------------------+-------+---------------------------------------------------------------+------------------+-----------+---------------+
| 1 | event_scheduler | localhost | NULL | Daemon | 14232 | Waiting on empty queue | NULL | 0 | 0 |
| 9 | repl | 192.168.2.101:53422 | NULL | Binlog Dump GTID | 11941 | Master has sent all binlog to slave; waiting for more updates | NULL | 0 | 0 |
| 14 | root | localhost | NULL | Query | 0 | starting | show processlist | 0 | 0 |
+----+-----------------+---------------------+-------+------------------+-------+---------------------------------------------------------------+------------------+-----------+---------------+
8 rows in set (0.00 sec)
root@(none)>
--从库状态
root@(none)>show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.2.100
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000014
Read_Master_Log_Pos: 194
Relay_Log_File: relay-bin.000005
Relay_Log_Pos: 407
Relay_Master_Log_File: mysql-bin.000014
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: 194
Relay_Log_Space: 695
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: 1
Master_UUID: 015d4d11-0363-11e9-bb6c-0800279a3030
Master_Info_File: /mysql/3306/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: 015d4d11-0363-11e9-bb6c-0800279a3030:1-4
Executed_Gtid_Set: 015d4d11-0363-11e9-bb6c-0800279a3030:1-4
Auto_Position: 1
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
root@(none)>
2.主库binlog被purge的情形
--停止从库，模拟从库宕机状态
root@pxc01>stop slave;
Query OK, 0 rows affected (0.02 sec)
root@pxc01>show slave status \G;
*************************** 1. row ***************************
Slave_IO_State:
Master_Host: 192.168.2.100
Master_User: repl
Master_Port: 3306
............
Slave_IO_Running: No
Slave_SQL_Running: No
--此时主库上的gtid_purged为空
root@(none)>show variables like '%gtid_purged%';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| gtid_purged | |
+---------------+-------+
1 row in set (0.01 sec)
root@(none)>
--查看主库binlog
root@pxc01>show binary logs;
+------------------+-----------+
| Log_name | File_size |
+------------------+-----------+
| mysql-bin.000009 | 154 |
| mysql-bin.000010 | 635 |
| mysql-bin.000011 | 201 |
| mysql-bin.000012 | 177 |
| mysql-bin.000013 | 1087 |
| mysql-bin.000014 | 706 |
+------------------+-----------+
--查看测试数据
root@pxc01>select * from tbx;
+------+
| id |
+------+
| 1 |
| 2 |
| 3 |
+------+
3 rows in set (0.00 sec)
root@pxc01>
--从主库删除记录
root@pxc01>delete from tbx;
Query OK, 3 rows affected (0.09 sec)
root@pxc01>
--切换日志
root@pxc01>flush logs;
Query OK, 0 rows affected (0.08 sec)
root@pxc01>
--新增记录
root@pxc01>insert into tbx values(4);
root@pxc01>insert into tbx values(5);
root@pxc01>insert into tbx values(6);
--查看主库binlog
root@pxc01>show binary logs;
+------------------+-----------+
| Log_name | File_size |
+------------------+-----------+
| mysql-bin.000009 | 154 |
| mysql-bin.000010 | 635 |
| mysql-bin.000011 | 201 |
| mysql-bin.000012 | 177 |
| mysql-bin.000013 | 1087 |
| mysql-bin.000014 | 1019 |
| mysql-bin.000015 | 962 |
+------------------+-----------+
--清理binlog
root@pxc01>purge binary logs to 'mysql-bin.000015';
Query OK, 0 rows affected (0.08 sec)
root@pxc01>show binary logs;
+------------------+-----------+
| Log_name | File_size |
+------------------+-----------+
| mysql-bin.000015 | 962 |
+------------------+-----------+
1 row in set (0.00 sec)
root@pxc01>
--此时可以看到相应的gtid_purged值
root@pxc01>show variables like '%gtid_purged%';
+---------------+------------------------------------------+
| Variable_name | Value |
+---------------+------------------------------------------+
| gtid_purged | 015d4d11-0363-11e9-bb6c-0800279a3030:1-7 |
+---------------+------------------------------------------+
1 row in set (0.01 sec)
root@pxc01>
--下面启动从库
root@(none)>start slave;
Query OK, 0 rows affected (0.06 sec)
root@(none)>show slave status \G;
*************************** 1. row ***************************
Slave_IO_State:
Slave_IO_Running: No
Slave_SQL_Running: Yes
Last_IO_Errno: 1236
Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'The slave is connecting using CHANGE MASTER TO MASTER_AUTO_POSITION = 1, but the master has purged binary logs containing GTIDs that the slave requires.'
Retrieved_Gtid_Set: 015d4d11-0363-11e9-bb6c-0800279a3030:1-6
Executed_Gtid_Set: 015d4d11-0363-11e9-bb6c-0800279a3030:1-6
Auto_Position: 1
-- 从库上gtid_purged参数，此时为空
root@(none)>show variables like '%gtid_purged%';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| gtid_purged | |
+---------------+-------+
1 row in set (0.01 sec)
root@(none)>
--停止从库
root@(none)>stop slave;
--下面尝试使用gtid_purged进行跳过事务。
root@(none)>set global gtid_purged = '015d4d11-0363-11e9-bb6c-0800279a3030:1-7';
ERROR 1840 (HY000): @@GLOBAL.GTID_PURGED can only be set when @@GLOBAL.GTID_EXECUTED is empty.
root@(none)>
提示:仅仅当GLOBAL.GTID_EXECUTED为空才能被设置
--查看从库当前的gtid_executed。gtid_executed肯定是不为空，且这些gtid记录在从库的binary log中
root@(none)>show global variables like '%gtid_executed%'\G
*************************** 1. row ***************************
Variable_name: gtid_executed
Value: 015d4d11-0363-11e9-bb6c-0800279a3030:1-6
*************************** 2. row ***************************
Variable_name: gtid_executed_compression_period
Value: 1000
2 rows in set (0.01 sec)
root@(none)>
--下面我们在从库上reset master，即清空从库binlog
root@(none)>reset master;
Query OK, 0 rows affected (0.10 sec)
--再次查看gtid_executed已经为空值
root@(none)>show global variables like '%gtid_executed%'\G
*************************** 1. row ***************************
Variable_name: gtid_executed
Value:
*************************** 2. row ***************************
Variable_name: gtid_executed_compression_period
Value: 1000
2 rows in set (0.01 sec)
root@(none)>
--此时再次设置gtid_purged的值
root@(none)>set global gtid_purged = '015d4d11-0363-11e9-bb6c-0800279a3030:1-7';
Query OK, 0 rows affected (0.06 sec)
--启动从库
root@(none)>start slave;
root@(none)>show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.2.100
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000015
Read_Master_Log_Pos: 962
Relay_Log_File: relay-bin.000006
Relay_Log_Pos: 1175
Relay_Master_Log_File: mysql-bin.000015
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: 962
Relay_Log_Space: 2141
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: 1
Master_UUID: 015d4d11-0363-11e9-bb6c-0800279a3030
Master_Info_File: /mysql/3306/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: 015d4d11-0363-11e9-bb6c-0800279a3030:1-6:8-10
Executed_Gtid_Set: 015d4d11-0363-11e9-bb6c-0800279a3030:1-10
Auto_Position: 1
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
注当前主从记录是不一致的：前期在主库delete的事务未传到从库，需要手动删除！
主库记录：
root@pxc01>select * from tbx;
+------+
| id |
+------+
| 4 |
| 5 |
| 6 |
+------+
3 rows in set (0.00 sec)
root@pxc01>
从库记录:
root@pxc01>select * from tbx;
+------+
| id |
+------+
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
| 6 |
+------+
6 rows in
