Task Scheduling

Creating a Scheduling Task

1. Log in to the management console.
2. Click in the upper left corner and select a region and project.
3. Click in the upper left corner, and under Databases, click Data Admin Service.
4. In the navigation pane on the left, choose Development Tool.

   You can also click Go to Development Tool on the overview page.

5. Locate the DB instance that you want to log in to and click Log In in the Operation column.
6. On the top menu bar, choose Background Tasks > Task Scheduling.
   

   You can create a scheduling task only after agreeing to save SQL statements in a database.

7. On the Scheduling Tasks tab, click Create Task.
8. On the displayed page, enter a task name and specify a scheduling type and execution time tolerance.
   Figure 1 Creating a task
   

   Table 1 Parameter description

   Parameter	Description
   Task Name	Task name, which is user-defined.
   Type	The options can be Immediate, Scheduled, and Periodic. You can set a scheduling type as required. Immediate: indicates that a scheduled task is executed immediately after being submitted. The task is executed only once. Scheduled: indicates that a task is executed at a scheduled point in time after being submitted. The task is executed only once. Periodic: indicates that a task is executed periodically at the specified time after being submitted.
   Execution Time Tolerance (s)	Refers to how many seconds the system keep executing this task after the expected execution time comes. The default value is 3600. The value ranges from 1 to 86,400.

9. Under SQL Statements, click Add. On the displayed page, set parameters as needed and click Save.
   Figure 2 Adding SQL statements
   

   Table 2 Parameter description

   Parameter	Description
   Group Name	Group name, which is user-defined.
   Instance	Target instance name.
   Database	Associated database.
   SQL Statements	You can manually input SQL statements or import existing SQL files.
   Skip Errors	Configuring this parameter is recommended. After this parameter is configured, the system will skip any errors detected when SQL statements in the SQL group are being executed. If this function is disabled, the system will stop executing SQL statements.
   Enable Transactions	Configuring this parameter is recommended. After this parameter is configured, SQL statements in the current SQL group will be executed as a transaction, and if a DML error occurs, a rollback will be performed. If this function is disabled, each SQL statement in the group is executed separately.
   Dependent SQL Group	The system executes all SQL statements in the dependent SQL group first and then those statements in the current group.
   Allow Concurrent Execution	Configuring this parameter is recommended. After this parameter is configured, the system will concurrently execute SQL statements in the current SQL group and other SQL groups, except for dependent SQL groups. CAUTION: SQL statements in the current SQL group are executed still in serial mode.

10. Click Submit at the bottom of the Create Task tab.

Managing Scheduling Tasks

Tasks are displayed on the Scheduling Tasks and Finished Tasks tab pages by status.

• Scheduling Tasks: The scheduling tasks are periodic tasks that are being scheduled or paused.

  On the Task Scheduling page, click the Scheduling Tasks tab.

  You can search for tasks by status, scheduling type, task ID, or task name.

  Figure 3 Searching for a task
  
  You can also perform the following operations on scheduling tasks:

  • View Details: Click it to view the task information.
    Figure 4 Details
    

    Click the name of a scheduling task to go to the Task Info page and click Manually Execute to trigger a scheduling immediately. After the task is successfully executed, view execution details on the Scheduling Execution Records page.

    In the SQL Groups area, click View Details. On the displayed page, view, modify, copy, and delete SQL statements.

    Figure 5 Managing SQL statements
    
  • View Execution Records: Click it to view the task execution details and logs.
  • View Log: Click it to view log details.
  • Terminate: Click it to stop a scheduled task. A stopped task will be moved to the Finished Tasks list.
  • Pause: Click it to pause a task. The task status changes from Scheduling to Pause. You can also click Resume to restore the scheduling.

• Finished Tasks: Tasks in the Finished Tasks list are periodic tasks that have been terminated or immediate and scheduled tasks that have completed.

  On the Task Scheduling page, click the Finished Tasks tab.

  You can search for tasks by status, scheduling type, task ID, or task name.

  Figure 6 Viewing task information
  

  You can also perform the following operations on scheduling tasks:

  • View Details: Click it to view the task information.

    Click the name of a finished task that is periodically scheduled or starts immediately. On the displayed page, click Manually Execute. After the execution completes, view execution details on the Scheduling Execution Records page.

    In the SQL Groups area, click View Details. On the displayed page, view, modify, copy, and delete SQL statements.

  • View Execution Records: Click it to view the task execution details, group execution status, SQL statements, and group logs.
  • View Log: Click it to view log details.
  • Delete: Click it to delete a task from the database.