Data Archiving

The data archiving tools consist of 5 Cli commands: set, cancel, pause, continue, and show. Users may use archiving tools to create archiving tasks, these archiving tasks start at the user specified date, and archives expired data (timestamp before expire time) into a target directory specified by user, the user can then perform other operations such as pause on the tasks.

SQL statements

Show Archiving Tasks

Show the data archiving tasks.

Syntax

SHOW ARCHIVING
SHOW ALL ARCHIVING
SHOW ARCHIVING ON <storage_group>
SHOW ALL ARCHIVING ON <storage_group>

• <storage_group> specifies the storage group to show archiving task on.
• all By default, only tasks in the READY, RUNNING, and PAUSED states are returned. You can view tasks in other states by adding the all parameter.

Example Result

+-------+---------------------------+-------------+------+---------------------------+---------------+----------------+
|task id|                submit time|storage group|status|                 start time|expire time(ms)|target directory|
+-------+---------------------------+-------------+------+---------------------------+---------------+----------------+
|      0|2022-1-1T00:00:00.000+08:00|      root.ln| READY|2023-1-1T00:00:00.000+08:00|         360000|            /tmp|
+-------+---------------------------+-------------+------+---------------------------+---------------+----------------+

Set Data Archiving Task

User submit data archiving task.

Syntax

SET ARCHIVING TO <storage_group> <start_time> <ttl> <target_dir>
SET ARCHIVING TO storage_group=<storage_group> start_time=<start_time> ttl=<ttl> target_dir=<target_dir>

• <storage_group> specifies the storage group to show archiving task on.
• <start_time> specifies the date to start the archiving task.
• <ttl> specifies the expire time for task, data with timestamp < now - ttl are archived, units in milliseconds.
• <target_dir> specifies the target directory to move the archived data, uses string for the path.

Example

SET ARCHIVING TO storage_group=root.ln start_time=2023-01-01 ttl=360000 target_dir="/tmp"
SET ARCHIVING TO root.ln 2023-01-01 360000 "/tmp"

Tips

• A= (such as storage_group=) in the Cli commands can be omitted, the order after omission must be the same as the above.
• The start time is in ISO 8601 format, so information such as hour/minute/second can be omitted, and it is set to 0 by default after being omitted.
• SET command is able to submit migration tasks for all storage groups by parameters like root.ln.**.

Cancel Archiving Task

Stop and delete the data archiving task. (Note: data that has been archived will not be put back into the database)

Syntax

CANCEL ARCHIVING <task_id>
CANCEL ARCHIVING ON <storage_group>

• <task_id> specifies the id of archiving task to cancel.
• <storage_group> specifies the storage group to cancel archiving task, if many exist cancel the one with the lowest start time.

Example

CANCEL ARCHIVING 0
CANCEL ARCHIVING ON root.ln

Pause Archiving Task

Suspend the data migration task.

Syntax

PAUSE ARCHIVING <task_id>
PAUSE ARCHIVING ON <storage_group>

• <task_id> specifies the id of archiving task to pause.
• <storage_group> specifies the storage group to pause archiving task, if many exist cancel the one with the lowest start time.

Example

PAUSE ARCHIVING 0
PAUSE ARCHIVING ON root.ln

Resume Archiving Task

Resume suspended data archiving tasks.

Syntax

RESUME ARCHIVING <task_id>
RESUME ARCHIVING ON <storage_group>

• <task_id> specifies the id of archiving task to resume.
• <storage_group> specifies the storage group to resume archiving task, if many exist cancel the one with the lowest start time.

Example

RESUME ARCHIVING 0
RESUME ARCHIVING ON root.ln

System Parameter Configuration

Name	Description	Data Type	Default Value
archiving_thread_num	The number of threads in the thread pool that executes archiving tasks.	int	2