Description:
Scenario:- Test replaying GR member to normal server with default parallel_type ('database') using ASYNC setup.
M1 <-> M2 -> S1
Actual Output:- Error message of ER1755 (upon seeing View_change) is not fully correct.
"2016-11-29T18:01:57.136895Z 43 [Warning] Slave: Cannot execute the current event group in the parallel mode. Encountered event View_change, relay-log name ./server-relay-log-ch1_2.000003, position 601 which prevents execution of this event group in parallel mode. Reason: the event is a part of a group that is unsupported in the parallel execution mode. Error_code: 1755"
This message part doesn't look good i.e. "which prevents execution of this event group in parallel mode. Reason: the event is a part of a group that is unsupported in the parallel execution mode."
Concerns/questions:-
1. In GR MTS type "DATABASE" is not supported. Thus, what should happen in topology GR (M1) -ASYN RPL-> S1 (MTS:database)? i.e. Is ER1755 OK? or Will it be good if this event gets logged as empty transaction?
2. Should we improve ER1755 in this case?
How to repeat:
Details:-
==========
MySQL Version: 8.0.1
Steps to repro:-
=================
Setup M1(GR) -ASYNC CHANNEL-> S1 (MTS type: database)
M1> START GROUP_REPLICATION;
S1> START SLAVE;
S1> SHOW SLAVE STATUS;
....
Last_SQL_Errno: 1755
Last_SQL_Error: Cannot execute the current event group in the parallel mode. Encountered event View_change, relay-log name ./server-relay-log-ch1_2.000003, position 601 which prevents execution of this event group in parallel mode. Reason: the event is a part of a group that is unsupported in the parallel execution mode.
....
Description: Scenario:- Test replaying GR member to normal server with default parallel_type ('database') using ASYNC setup. M1 <-> M2 -> S1 Actual Output:- Error message of ER1755 (upon seeing View_change) is not fully correct. "2016-11-29T18:01:57.136895Z 43 [Warning] Slave: Cannot execute the current event group in the parallel mode. Encountered event View_change, relay-log name ./server-relay-log-ch1_2.000003, position 601 which prevents execution of this event group in parallel mode. Reason: the event is a part of a group that is unsupported in the parallel execution mode. Error_code: 1755" This message part doesn't look good i.e. "which prevents execution of this event group in parallel mode. Reason: the event is a part of a group that is unsupported in the parallel execution mode." Concerns/questions:- 1. In GR MTS type "DATABASE" is not supported. Thus, what should happen in topology GR (M1) -ASYN RPL-> S1 (MTS:database)? i.e. Is ER1755 OK? or Will it be good if this event gets logged as empty transaction? 2. Should we improve ER1755 in this case? How to repeat: Details:- ========== MySQL Version: 8.0.1 Steps to repro:- ================= Setup M1(GR) -ASYNC CHANNEL-> S1 (MTS type: database) M1> START GROUP_REPLICATION; S1> START SLAVE; S1> SHOW SLAVE STATUS; .... Last_SQL_Errno: 1755 Last_SQL_Error: Cannot execute the current event group in the parallel mode. Encountered event View_change, relay-log name ./server-relay-log-ch1_2.000003, position 601 which prevents execution of this event group in parallel mode. Reason: the event is a part of a group that is unsupported in the parallel execution mode. ....