Oracle PL/SQL for DBAs

Job Class

A job class is a collection of properties. I can create a job class with DBMS_SCHEDULER’s CREATE_JOB_CLASS procedure . When I create a job, I can specify the name of an already created job class using the job_class parameter in CREATE_JOB. Here is how to create a scheduler job class that follows the resource allocation group OLTP_GROUP.

      1  BEGIN
      2     DBMS_SCHEDULER.create_job_class
      3             (job_class_name               => 'OLTP_JOBS',
      4              logging_level                => dbms_scheduler.logging_full,
      5              log_history                  => 45,
      6              resource_consumer_group      => 'OLTP_GROUP',
      7              comments                     => 'OLTP Related Jobs'
      8             );
      9 END;

Let’s examine the lines in detail in the following table.

Line	Description
3	Name of the job class.
4	When a job executes, it creates a log of its activities in a SYS-owned table named SCHEDULER$_EVENT_LOG. You can expose this table to others via the DBA_SCHEDULER_JOB_LOG view . The log entries can be full or partial. (See the "Managing Logging" section for an explanation.)
5	If the execution of the job is logged, then the log entries must be purged periodically; otherwise, the log will become unmanageably large. The log_history parameter determines how many days of logs must be kept. The default is 30 days. In this example, I increase the number of days to 45.
6	This job class is assigned the resource group OLTP_GROUP, which governs the resource allocation and utilization of the jobs defined in this job class.
7	Comments for this job class.

After the job class is created, I can check its attributes ...