Note
This view is available starting with V4.2.0.
Purpose
This view displays the history of all executed Transfer tasks in the current tenant.
Columns
| Column | Type | Nullable | Description |
|---|---|---|---|
| TASK_ID | bigint(20) | NO | The ID of the Transfer task. |
| CREATE_TIME | timestamp(6) | YES | The start time of the task. |
| MODIFY_TIME | timestamp(6) | YES | The completion time of the task, including the time when the task was canceled. |
| SRC_LS | bigint(20) | NO | The source log stream (the log data stream generated by the data source). |
| DEST_LS | bigint(20) | NO | The destination log stream. |
| PART_LIST | longtext | YES | The list of partitions, including user table partitions and global index partitions. |
| PART_COUNT | bigint(20) | YES | The number of partitions in the partition list. |
| NOT_EXIST_PART_LIST | longtext | YES | The list of partitions that were planned to be executed in this task but did not exist when the lock was added. |
| LOCK_CONFLICT_PART_LIST | longtext | YES | The list of partitions that were planned to be executed in this task but experienced lock conflicts when the lock was added. |
| TABLE_LOCK_TABLET_LIST | longtext | YES | The list of tablets for partition-level table locks successfully added when the task entered the START state. This list is used for table lock migration and contains only tablets corresponding to partitions in the PART_LIST. |
| TABLET_LIST | longtext | YES | The complete list of tablets involved in this Transfer operation. This list includes not only the tablets listed in the PART_LIST but also tablets associated with local index tables and LOB auxiliary tables. |
| TABLET_COUNT | bigint(20) | YES | The number of tablets in the tablet list. |
| START_SCN | bigint(20) unsigned | YES | The SCN when the Transfer task was initiated. |
| FINISH_SCN | bigint(20) unsigned | YES | The SCN when the Transfer task was completed. |
| STATUS | varchar(64) | NO | The status of the task
|
| TRACE_ID | varchar(64) | NO | The Trace ID of the entire task. |
| RESULT | bigint(20) | YES | The result of the task. |
| BALANCE_TASK_ID | bigint(20) | NO | The ID of the associated load balancing task. This Transfer task is a subtask generated by the corresponding load balancing task. |
| TABLE_LOCK_OWNER_ID | bigint(20) | YES | When a table lock is added, the system generates an owner_id for each table lock to identify the owner of the lock. When releasing a table lock, the corresponding owner_id must be provided so that the system can correctly identify and release the lock. |
| COMMENT | longtext | YES | The comment information. It records the reasons for the task being stuck, diagnostic information, and the failure status of the task. |
Sample query
Query the history of all executed transfer tasks in the current tenant.
obclient[oceanbase]> SELECT * FROM oceanbase.DBA_OB_TRANSFER_TASK_HISTORY\G
The query result is as follows:
*************************** 1. row ***************************
TASK_ID: 1
CREATE_TIME: 2025-05-09 14:29:08.549102
FINISH_TIME: 2025-05-09 14:29:13.075254
SRC_LS: 1001
DEST_LS: 1002
PART_LIST: 500002:500008,500002:500011,500002:500014
PART_COUNT: 3
NOT_EXIST_PART_LIST: NULL
LOCK_CONFLICT_PART_LIST: NULL
TABLE_LOCK_TABLET_LIST: 200003,200006,200009
TABLET_LIST: 200003:0,200006:0,200009:0
TABLET_COUNT: 3
START_SCN: 1746772151864500001
FINISH_SCN: 1746772152922156001
STATUS: COMPLETED
TRACE_ID: YB42AC1E87CF-0006349B5C8113E1-0-0
RESULT: 0
BALANCE_TASK_ID: 318280
TABLE_LOCK_OWNER_ID: 318338
COMMENT:
*************************** 2. row ***************************
TASK_ID: 2
CREATE_TIME: 2025-05-09 14:29:47.593154
FINISH_TIME: 2025-05-09 14:29:48.912310
SRC_LS: 1002
DEST_LS: 1001
PART_LIST: 500002:500008,500002:500011,500002:500014
PART_COUNT: 3
NOT_EXIST_PART_LIST: NULL
LOCK_CONFLICT_PART_LIST: NULL
TABLE_LOCK_TABLET_LIST: 200003,200006,200009
TABLET_LIST: 200003:1,200006:1,200009:1
TABLET_COUNT: 3
START_SCN: 1746772187916956001
FINISH_SCN: 1746772188599916001
STATUS: COMPLETED
TRACE_ID: YB42AC1E87CF-0006349B5C8113EC-0-0
RESULT: 0
BALANCE_TASK_ID: 318454
TABLE_LOCK_OWNER_ID: 318466
COMMENT:
*************************** 3. row ***************************
TASK_ID: 3
CREATE_TIME: 2025-05-09 14:30:08.631035
FINISH_TIME: 2025-05-09 14:30:13.855965
SRC_LS: 1001
DEST_LS: 1003
PART_LIST: 500002:500008,500002:500011,500002:500014
PART_COUNT: 3
NOT_EXIST_PART_LIST: NULL
LOCK_CONFLICT_PART_LIST: NULL
TABLE_LOCK_TABLET_LIST: 200003,200006,200009
TABLET_LIST: 200003:2,200006:2,200009:2
TABLET_COUNT: 3
START_SCN: 1746772212533757001
FINISH_SCN: 1746772213595007001
STATUS: COMPLETED
TRACE_ID: YB42AC1E87CF-0006349B5C8113F8-0-0
RESULT: 0
BALANCE_TASK_ID: 318539
TABLE_LOCK_OWNER_ID: 318605
COMMENT:
3 rows in set
References
View tablet-level load balancing tasks (Task) in the current tenant: DBA_OB_TRANSFER_TASKS
View log stream-level load balancing jobs (Job) in the current tenant:
View log stream-level load balancing tasks (Task) in the current tenant:
View Transfer Partition tasks (Task) in the current tenant:
For more information about data load balancing, see Data load balancing.