25.12.11.5 The replication_applier_status_by_coordinator Table

For a multithreaded replica, the replica uses multiple worker threads and a coordinator thread to manage them, and this table shows the status of the coordinator thread. For a single-threaded replica, this table is empty. For a multithreaded replica, the replication_applier_status_by_worker table shows the status of the worker threads.

The replication_applier_status_by_coordinator table has these columns:

• CHANNEL_NAME

  The replication channel which this row is displaying. There is always a default replication channel, and more replication channels can be added. See Section 16.2.2, “Replication Channels” for more information.

• THREAD_ID

  The SQL/coordinator thread ID.

• SERVICE_STATE

  ON (thread exists and is active or idle) or OFF (thread no longer exists).

• LAST_ERROR_NUMBER, LAST_ERROR_MESSAGE

  The error number and error message of the most recent error that caused the SQL/coordinator thread to stop. An error number of 0 and message which is an empty string means “no error”. If the LAST_ERROR_MESSAGE value is not empty, the error values also appear in the replica's error log.

  Issuing RESET MASTER or RESET SLAVE resets the values shown in these columns.

  All error codes and messages displayed in the LAST_ERROR_NUMBER and LAST_ERROR_MESSAGE columns correspond to error values listed in Server Error Message Reference.

• LAST_ERROR_TIMESTAMP

  A timestamp in YYMMDD hh:mm:ss format that shows when the most recent SQL/coordinator error occurred.

TRUNCATE TABLE is not permitted for the replication_applier_status_by_coordinator table.

The following table shows the correspondence between replication_applier_status_by_coordinator columns and SHOW SLAVE STATUS columns.

replication_applier_status_by_coordinator Column	SHOW SLAVE STATUS Column
THREAD_ID	None
SERVICE_STATE	Slave_SQL_Running
LAST_ERROR_NUMBER	Last_SQL_Errno
LAST_ERROR_MESSAGE	Last_SQL_Error
LAST_ERROR_TIMESTAMP	Last_SQL_Error_Timestamp