Oracle7 Server Distributed Systems Volume II: Replicated Data

Diagnosing Problems with Job Queues

If a job is not executed as expected, check the following:

Check the NEXT_DATE value in the DBA_JOBS view to ensure that the job was properly scheduled for execution.

After determining that the job execution interval has passed, check the FAILURES and BROKEN values in the DBMS_JOBS view.

If the job failed to execute, check the alert log and trace files for error information and fix the error. If the job was not broken, it will ultimately be re-executed. If the job was broken, or if you want to force immediate re-execution of the job, call DBMS_JOB.RUN after fixing the job.

If the job was never executed, there may be a problem with the availability of background processes. Check the initialization parameter JOB_QUEUE_PROCESSES to determine the maximum number of background processes available and JOB_QUEUE_INTERVAL to determine how frequently each background processes wakes up. The DBA_JOBS_RUNNING view describes what jobs these processes are currently running (you may have a problem with a runaway job), and the alert log and trace file can provide you with additional information about potential problems with the background process.