Removing redundant processes from the NJProcess table

The NJProcess table stores the states of NexJ processes that occur periodically. The current state of a process also displays in the Process page in NexJ Admin Console.

In NexJ Studio, you can create a batch job that will periodically clean up old processes. The batch job must define which processes to delete and must invoke the ETLDelete ETL activity to ensure the NJProcess table and all related tables are also cleaned up. Consider the following when creating the batch job:

• Specify that the batch job delete only completed, cancelled, failed, or completed with errors processes. Running, paused, or waiting processes should not be deleted.
• Use a threshold to delete only processes that are older than a specific time period, for example processes that are older than 12 months.

The following sample Scheme code deletes processes that are older than 1 year and are completed, cancelled, failed, or completed with errors.

(define threshold (date-add-years (now) -1))
(define where
   `(and
      (< (@ createTime) ,threshold) 
      (in? 
         (@ status) 
         ,(ProcessStatusEnum'get 'COMPLETED) 
         ,(ProcessStatusEnum'get 'CANCELLED) 
         ,(ProcessStatusEnum'get 'FAILED) 
         ,(ProcessStatusEnum'get 'ERRORS)
      )
   )
)

(begin-privileged
   (SysETLActivity'invoke "ETLDelete" () () SysProcess SysProcess where '())
)

To create the batch job:

1. In NexJ Studio, create a new class.
2. In the Overview tab, define SysBatchJob as the base class of the new class.
3. Override the run event and add a main action that contains the Scheme code that you created earlier:
   1. Open the Events tab. On the top half of the screen, next to the Events list, click the Override Base Events button 

      

      .
   2. In the Override Base Events dialog, add the run event.
   3. In the Events tab, in the Actions subtab, click the Add button 

      

       and select main.
   4. In the Script subtab, insert your Scheme code into the text field below the Method field.
4. Specify how often to run the batch job:
   1. Open the Attributes tab. On the top half of the screen, next to the Attributes list, click the Override Base Attributes button 

      

      .
   2. In the Override Base Attributes dialog, add the period event.
   3. In the Attributes tab, in the Value subtab, in the Value field, specify the number of minutes between each invocation of the batch job. For example, specify 10080 to create a weekly batch job.
5. Seed the batch job:
   1. In the Overview tab, click the Select button 

      

       in the Aspects field.
   2. In the Select Aspects dialog, include the PERSISTENCE_INITIALIZER aspect.
   3. Open the Events tab. On the top half of the screen, next to the Events list, click the Override Base Events button 

      

      .
   4. In the Override Base Events dialog, add the initializePersistence event.
   5. In the Events list, select the initializePersistence event.
   6. In the Events tab, in the Actions subtab, click the Add button 

      

       and select main.
   7. In the Script subtab, insert Scheme code that seeds the batch job in the Condition and Method fields. For example:
      
      • In Condition, enter (null? (read-instance ProcessBatchJob '() '() #f))
      • In Method, enter ProcessBatchJob'new) (pre-commit)
6. Save and close the new class.

The batch job will be seeded the next time the server starts if the server is set to reseed.