While defining a schedule it is not required to launch the schedule immediately afterwards. A scheduled task can be created in a disabled status so that the user can schedule it at a later time.
All tasks leave a log that can be used to validate that the task was successful or to find out if a scheduled task failed and why. The user should know how and when to purge it so it doesn't grow too big.
The DBMS_SCHEDULER.ENABLE enables a Scheduler component, such as a program, job, window or window group, and DBMS_SCHEDULER.DISABLE disables components.
This procedure enables a job belonging to the demo Scheduler. In the previous section the TEST_MINUTELY Scheduler job was defined.
EXEC sys.dbms_scheduler.enable( '"OSCHEDULER"."TEST_MINUTELY"' );