DBA_OB_TENANT_EVENT_HISTORY

Purpose

The DBA_OB_TENANT_EVENT_HISTORY view displays the operation records of the current tenant.

Columns

Sample tenant events

The following examples show tenant events in the TENANT ROLE CHANGE (primary/standby tenant switch), SERVICE NAME (service name), and DBMS_BALANCE modules.

The NAME and VALUE values of the events vary based on the module operations performed by the user.

TENANT ROLE CHANGE

The TENANT ROLE CHANGE module provides the following operations: FAILOVER TO PRIMARY, SWITCHOVER TO PRIMARY, and SWITCHOVER TO STANDBY.

• FAILOVER TO PRIMARY operation

  When you initiate a FAILOVER TO PRIMARY operation, the following important events are recorded in the tenant event log table.

  • FAILOVER TO PRIMARY START

    This event records the specific time when the ALTER SYSTEM ACTIVATE STANDBY command is executed, along with relevant tenant information.

    Attribute	Value
    NAME1: STMT_STR	VALUE1: The text of the command entered by the user
    NAME2: TENANT_INFO	VALUE2: The status or information of the tenant at the time the command was initiated

  • FAILOVER TO PRIMARY END

    This event records the exact time when the ALTER SYSTEM ACTIVATE STANDBY command is completed, including relevant tenant information, the final status of the log streams, and the time taken for key steps.

    Attribute	Value
    NAME1: STMT_STR	VALUE1: The text of the command entered by the user
    NAME2: TENANT_INFO	VALUE2: The status or information of the tenant at the end of the command
    NAME3: FAILOVER_SCN	VALUE3: The synchronization point after the tenant failover
    NAME4: COST_DETAIL	VALUE4: The time taken for each stage of the command execution, in microseconds
    NAME5: ALL_LS	VALUE5: The status of all log streams when the tenant modifies the ACCESS MODE

• SWITCHOVER TO PRIMARY operation

  When you initiate a SWITCHOVER TO PRIMARY operation, the following important events are recorded in the tenant event log table.

  • SWITCHOVER TO PRIMARY START

    This event records the specific time when the ALTER SYSTEM SWITCHOVER TO PRIMARY command is executed, along with relevant tenant information.

    Attribute	Value
    NAME1: STMT_STR	VALUE1: The text of the command entered by the user
    NAME2: TENANT_INFO	VALUE2: The status or information of the tenant at the time the command was initiated

  • WAIT LOG SYNC

    This event records information about log synchronization for the tenant. When you execute the ALTER SYSTEM SWITCHOVER TO PRIMARY command, the involved tenant must wait until all the latest log records are synchronized from the current primary tenant to ensure data consistency and integrity.

    Attribute	Value
    NAME1: IS_SYS_LS_SYNCED	VALUE1: Whether the system log stream of the tenant is synchronized
    NAME2: IS_ALL_LS_SYNCED	VALUE2: Whether all log streams of the tenant are synchronized
    NAME3: NON_SYNC_INFO	VALUE3: If there are unsynchronized log streams, the system will display the number of unsynchronized log streams and provide information about the five log streams with the slowest synchronization speed.

  • SWITCHOVER TO PRIMARY END

    This event records the exact time when the ALTER SYSTEM SWITCHOVER TO PRIMARY command is completed, including relevant tenant information, the final status of the log streams, and the time taken for key steps.

    Attribute	Value
    NAME1: STMT_STR	VALUE1: The text of the command entered by the user
    NAME2: TENANT_INFO	VALUE2: The status or information of the tenant at the end of the command
    NAME3: SWITCHOVER_SCN	VALUE3: The synchronization point after the tenant switchover
    NAME4: COST_DETAIL	VALUE4: The time taken for each stage of the command execution, in microseconds
    NAME5: ALL_LS	VALUE5: The status of all log streams when the tenant modifies the ACCESS MODE

• SWITCHOVER TO STANDBY operation

  When you initiate a SWITCHOVER TO STANDBY operation, the following important events are recorded in the tenant event log table.

  • SWITCHOVER TO STANDBY START

    This event records the specific time when the ALTER SYSTEM SWITCHOVER TO STANDBY command is executed, along with relevant tenant information.

    Attribute	Value
    NAME1: STMT_STR	VALUE1: The text of the command entered by the user
    NAME2: TENANT_INFO	VALUE2: The status or information of the tenant at the time the command was initiated

  • SWITCHOVER TO STANDBY END

    This event records the exact time when the ALTER SYSTEM SWITCHOVER TO STANDBY command is completed, including relevant tenant information, the final status of the log streams, and the time taken for key steps.

    Attribute	Value
    NAME1: STMT_STR	VALUE1: The text of the command entered by the user
    NAME2: TENANT_INFO	VALUE2: The status or information of the tenant at the end of the command
    NAME3: SWITCHOVER_SCN	VALUE3: The synchronization point after the tenant switchover
    NAME4: COST_DETAIL	VALUE4: The time taken for each stage of the command execution, in microseconds
    NAME5: ALL_LS	VALUE5: The status of all log streams when the tenant modifies the ACCESS MODE

SERVICE NAME

The SERVICE NAME module contains the CREATE SERVICE, DELETE SERVICE, START SERVICE, and STOP SERVICE operations.

You can use the TRACE_ID to trace the events of these operations. For example, you can find the event of creating a service and trace the broadcast triggered by the event based on the TRACE_ID of the event.

• CREATE SERVICE

  When a user tenant initiates a service creation, the following events are recorded.

  • BROADCAST SERVICE NAME

    This event records the content of the broadcast, the list of OBServer nodes that receive the broadcast, and the list of OBServer nodes that successfully receive the broadcast. When you execute the ALTER SYSTEM CREATE SERVICE command, the OBServer node that initiates the command broadcasts the current service name of the tenant to all OBServer nodes where the units of the tenant are located.

    Attribute	Value
    NAME1: EPOCH	VALUE1: The version of the current service name information of the tenant for the broadcast.
    NAME2: TARGET_SERVICE_NAME_ID	VALUE2: The service_name_id of the event that triggers the broadcast.
    NAME3: SERVICE_NAME_LIST	VALUE3: The service name information of the tenant.
    NAME4: SERVICE_NAME_COMMAND_TYPE	VALUE4: The type of the operation that triggers the broadcast.
    NAME5: TARGET_SERVERS_LIST	VALUE5: The list of OBServer nodes where the units of the tenant are located, excluding the permanently offline nodes.
    NAME6: SUCCESS_SERVERS_LIST	VALUE6: The list of OBServer nodes that successfully receive the broadcast.

  • CREATE SERVICE

    This event records the service name to be created and the detailed information after the service is created. After you execute the ALTER SYSTEM CREATE SERVICE command, this event is generated.

    Attribute	Value
    NAME1: SERVICE_NAME_STRING	VALUE1: The new service name to be created.
    NAME2: CREATED_SERVICE_NAME	VALUE2: The service name information.

• DELETE SERVICE

  When a user tenant initiates a service deletion, the following events are recorded.

  • DELETE SERVICE

    This event records the information at the time the command is initiated. After you execute the ALTER SYSTEM DELETE SERVICE command, this event is generated.

    Attribute	Value
    NAME1: DELETED_SERVICE_NAME	VALUE1: The service name information to be deleted.

• START SERVICE

  When a user tenant initiates a service start, the following events are recorded.

  • BROADCAST SERVICE NAME

    This event records the content of the broadcast, the list of OBServer nodes that receive the broadcast, and the list of OBServer nodes that successfully receive the broadcast. When you execute the ALTER SYSTEM SERVICE NAME command, the OBServer node that initiates the command broadcasts the current service name of the tenant to all OBServer nodes where the units of the tenant are located.

    Attribute	Value
    NAME1: EPOCH	VALUE1: The version of the current service name information of the tenant for the broadcast.
    NAME2: TARGET_SERVICE_NAME_ID	VALUE2: The service _name _id of the event that triggers the broadcast.
    NAME3: SERVICE_NAME_LIST	VALUE3: The service_name of the tenant.
    NAME4: SERVICE_NAME_COMMAND_TYPE	VALUE4: The type of the operation that triggers the broadcast.
    NAME5: TARGET_SERVERS_LIST	VALUE5: The list of OBServer nodes where the units of the tenant are located, excluding the permanently offline nodes.
    NAME6: SUCCESS_SERVERS_LIST	VALUE6: The list of OBServer nodes that successfully receive the broadcast.

  • START SERVICE

    This event records the information at the time the command is initiated and the information at the time the command is completed. After you execute the ALTER SYSTEM START SERVICE command, this event is generated.

    Attribute	Value
    NAME1: SERVICE_NAME_BEFORE	VALUE1: The service name information before the service is started.
    NAME2: SERVICE_NAME_AFTER	VALUE2: The service name information after the service is started.

• STOP SERVICE

  When a user tenant initiates a service stop, the following events are recorded.

  • KILL CONNECTIONS OF SERVICE NAME

    Each OBServer node terminates the connections established by the stopped service name and generates a record in the tenant event view. If no connections are established by the stopped service name on an OBServer node, this event is not recorded in the table.

    Attribute	Value
    NAME1: SERVICE_NAME	VALUE1: The service name information of the service to be stopped.
    NAME2: KILLED_CONNECTIONS_COUNT	VALUE2: The number of connections that are terminated.
    NAME3: KILLED_CONNECTIONS_LIST	VALUE3: The IDs of the connections that are terminated.

  • BROADCAST SERVICE NAME

    This event records the content of the broadcast, the list of OBServer nodes that receive the broadcast, and the list of OBServer nodes that successfully receive the broadcast. When you execute the ALTER SYSTEM STOP SERVICE command, the OBServer node that initiates the command broadcasts the current service name of the tenant to all OBServer nodes where the units of the tenant are located.

    Attribute	Value
    NAME1: EPOCH	VALUE1: The version of the current service name information of the tenant for the broadcast.
    NAME2: TARGET_SERVICE_NAME _ID	VALUE2: The service _name _id of the event that triggers the broadcast.
    NAME3: SERVICE_NAME_LIST	VALUE3: The service_name of the tenant.
    NAME4: SERVICE_NAME_COMMAND_TYPE	VALUE4: The type of the operation that triggers the broadcast.
    NAME5: TARGET_SERVERS_LIST	VALUE5: The list of OBServer nodes where the units of the tenant are located, excluding the permanently offline nodes.
    NAME6: SUCCESS_SERVERS_LIST	VALUE6: The list of OBServer nodes that successfully receive the broadcast.

  • STOP SERVICE

    This event records the information at the time the command is initiated and the information at the time the command is completed. After you execute the ALTER SYSTEM STOP SERVICE command, this event is generated.

    Attribute	Attribute Value
    NAME1: SERVICE_NAME_BEFORE	VALUE1: Information about the service name before the service is stopped.
    NAME2: SERVICE_NAME_AFTER	VALUE2: Information about the service name after the service is stopped.

DBMS_BALANCE

The DBMS_BALANCE module provides the following four operations: TRIGGER PARTITION BALANCE, SET BALANCE WEIGHT, CLEAR BALANCE WEIGHT, and CLEAR EXPIRED BALANCE WEIGHT.

• TRIGGER PARTITION BALANCE

  When you execute the DBMS_BALANCE.TRIGGER_PARTITION_BALANCE operation, the system records a TRIGGER PARTITION BALANCE event in the tenant event record table.

  The TRIGGER PARTITION BALANCE event records the specific time when the DBMS_BALANCE.TRIGGER_PARTITION_BALANCE command was executed and the related parameters.

  Attribute	Value
  NAME1: BALANCE_TIMEOUT_S	VALUE1: The timeout parameter when the balance is triggered, in seconds.

• SET BALANCE WEIGHT

  When you execute the DBMS_BALANCE.SET_BALANCE_WEIGHT operation, the system records a SET BALANCE WEIGHT event in the tenant event record table.

  The SET BALANCE WEIGHT event records the specific time when the DBMS_BALANCE.SET_BALANCE_WEIGHT command was executed and the related parameters.

  Attribute	Value
  NAME1: WEIGHT	VALUE1: The weight of the partition.
  NAME2: DATABASE_NAME	VALUE2: The name of the database to which the partition belongs.
  NAME3: TABLE_NAME	VALUE3: The name of the table to which the partition belongs.
  NAME4: PARTITION_NAME	VALUE4: The name of the partition.
  NAME5: SUBPARTITION_NAME	VALUE5: The name of the subpartition.

• CLEAR BALANCE WEIGHT

  When you execute the DBMS_BALANCE.CLEAR_BALANCE_WEIGHT operation, the system records a CLEAR BALANCE WEIGHT event in the tenant event record table.

  The CLEAR BALANCE WEIGHT event records the specific time when the DBMS_BALANCE.CLEAR_BALANCE_WEIGHT command was executed and the related parameters.

  Attribute	Value
  NAME1: DATABASE_NAME	VALUE1: The name of the database to which the partition belongs.
  NAME2: TABLE_NAME	VALUE2: The name of the table to which the partition belongs.
  NAME3: PARTITION_NAME	VALUE3: The name of the partition.
  NAME4: SUBPARTITION_NAME	VALUE4: The name of the subpartition.

• CLEAR EXPIRED BALANCE WEIGHT

  When the background thread clears the weights of expired partitions, the system records a CLEAR EXPIRED BALANCE WEIGHT event in the tenant event record table.

  The CLEAR EXPIRED BALANCE WEIGHT event records the specific time when the background thread cleared the weights of expired partitions and the related parameters.

  Attribute	Value
  NAME1: TABLE_NAME	VALUE1: The name of the table to which the partition belongs.
  NAME2: PARTITION_NAME	VALUE2: The name of the partition.
  NAME3: SUBPARTITION_NAME	VALUE3: The name of the subpartition.

Sample query

Query the historical operation records of the current tenant and display the first record.

obclient [SYS]> SELECT * FROM SYS.DBA_OB_TENANT_EVENT_HISTORY WHERE ROWNUM = 1\G

The query result is as follows:

*************************** 1. row ***************************
 TIMESTAMP: 2023-12-14 14:33:20.321725
    MODULE: TENANT ROLE CHANGE
     EVENT: SWITCHOVER TO STANDBY END
     NAME1: STMT_STR
    VALUE1: ALTER SYSTEM SWITCHOVER TO STANDBY TENANT backup_mysql_tenant
     NAME2: TENANT_INFO
    VALUE2: {tenant_id:1002, tenant_role:"STANDBY", switchover_status:"NORMAL", switchover_epoch:1702535600271677, sync_scn:1702535620070597000, replayable_scn:1702535620070597000, readable_scn:1702535620070597000, recovery_until_scn:4611686018427387903, log_mode:"ARCHIVELOG", max_ls_id:1003}
     NAME3: SWITCHOVER_SCN
    VALUE3: 1702535620070597000
     NAME4: COST_DETAIL
    VALUE4: WAIT_LOG_END: 100190, CHANGE_ACCESS_MODE: 47261, OTHERS: 136839
     NAME5: ALL_LS
    VALUE5: NORMAL: 1, 1001, 1002, 1003
     NAME6: NULL
    VALUE6:
EXTRA_INFO: NULL
    SVR_IP: 100.xx.xx.xx
  SVR_PORT: 13324
  TRACE_ID: Y340C64586BD4-00060C724AEB962B-0-0
 COST_TIME: 284290
  RET_CODE: 0
 ERROR_MSG: NULL
1 row in set

References

• Create a service
• View the status of a service
• Start a service
• Pause a service
• Delete a service