Note
This view was introduced in OceanBase Database V4.2.0.
Purpose
The oceanbase.DBA_OB_BALANCE_TASK_HISTORY view displays the history of all load balancing tasks executed in the current tenant.
Columns
| Column | Type | Nullable? | Description |
|---|---|---|---|
| TASK_ID | bigint(20) | NO | The ID of the load balancing task. |
| CREATE_TIME | timestamp(6) | NO | The start time of the task. |
| FINISH_TIME | timestamp(6) | NO | The end time of the task, which can be the time when the task was executed or canceled. |
| TASK_TYPE | varchar(64) | NO | The type of the task. Valid values:
|
| SRC_LS | bigint(20) | NO | The source log stream, which is generated at 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. |
| FINISHED_PART_LIST | longtext | YES | The list of partitions for which load balancing has been completed. |
| PART_COUNT | bigint(20) | YES | The number of partitions in the partition list. |
| FINISHED_PART_COUNT | bigint(20) | YES | The number of partitions for which load balancing has been completed. |
| LS_GROUP_ID | bigint(20) | NO | The ID of the log stream group. |
| STATUS | varchar(64) | NO | The status of the task. Valid values:
|
| PARENT_LIST | varchar(1024) | YES | The list of parent tasks. |
| CHILD_LIST | varchar(1024) | YES | The list of subtasks. |
| CURRENT_TRANSFER_TASK_ID | bigint(20) | NO | The ID of the transfer task triggered by the current load balancing task. |
| JOB_ID | bigint(20) | NO | The ID of the job to which the current task belongs. |
| COMMENT | longtext | YES | The comments. |
| BALANCE_STRATEGY | varchar(64) | YES | The load balancing strategy for the load balancing task.
NoteThis column was introduced in OceanBase Database V4.2.4. |
Sample query
Query the history of all load balancing tasks executed in the current tenant.
obclient [oceanbase]> SELECT * FROM oceanbase.DBA_OB_BALANCE_TASK_HISTORY\G
Query result:
*************************** 1. row ***************************
TASK_ID: 318280
CREATE_TIME: 2025-05-09 14:29:05.504906
FINISH_TIME: 2025-05-09 14:29:13.589729
TASK_TYPE: LS_SPLIT
SRC_LS: 1001
DEST_LS: 1002
PART_LIST: NULL
FINISHED_PART_LIST: 500002:500008,500002:500011,500002:500014
PART_COUNT: 0
FINISHED_PART_COUNT: 3
LS_GROUP_ID: 1001
STATUS: COMPLETED
PARENT_LIST: NULL
CHILD_LIST: NULL
CURRENT_TRANSFER_TASK_ID: -1
JOB_ID: 318278
COMMENT: NULL
BALANCE_STRATEGY: LS balance by expand
*************************** 2. row ***************************
TASK_ID: 318454
CREATE_TIME: 2025-05-09 14:29:45.565764
FINISH_TIME: 2025-05-09 14:29:53.633471
TASK_TYPE: LS_MERGE
SRC_LS: 1002
DEST_LS: 1001
PART_LIST: NULL
FINISHED_PART_LIST: 500002:500008,500002:500011,500002:500014
PART_COUNT: 0
FINISHED_PART_COUNT: 3
LS_GROUP_ID: 1001
STATUS: COMPLETED
PARENT_LIST: NULL
CHILD_LIST: NULL
CURRENT_TRANSFER_TASK_ID: -1
JOB_ID: 318453
COMMENT: NULL
BALANCE_STRATEGY: LS balance by shrink
*************************** 3. row ***************************
TASK_ID: 318539
CREATE_TIME: 2025-05-09 14:30:05.606117
FINISH_TIME: 2025-05-09 14:30:14.069126
TASK_TYPE: LS_SPLIT
SRC_LS: 1001
DEST_LS: 1003
PART_LIST: NULL
FINISHED_PART_LIST: 500002:500008,500002:500011,500002:500014
PART_COUNT: 0
FINISHED_PART_COUNT: 3
LS_GROUP_ID: 1001
STATUS: COMPLETED
PARENT_LIST: NULL
CHILD_LIST: NULL
CURRENT_TRANSFER_TASK_ID: -1
JOB_ID: 318537
COMMENT: NULL
BALANCE_STRATEGY: LS balance by expand
3 rows in set
References
Query the load balancing tasks (Task) at the log stream level in the current tenant: DBA_OB_BALANCE_TASKS
Query the load balancing jobs (Job) at the log stream level in the current tenant:
Query the load balancing tasks (Task) at the tablet level in the current tenant:
Query the transfer partition tasks (Task) in the current tenant:
For more information about data load balancing, see Data load balancing.