11. From the database home page take the Server tab, then the Windows
link in the Oracle Scheduler section. Select the DAYTIME window, and
click
DELETE
.
Two-Minute Drill
Create a Job, Program, and Schedule
• A job can specify what to do and when to do it, or it can point to a program
and/or a schedule.
• A job (or its program) can be an anonymous PL/SQL block, a stored procedure,
or an external operating system command or script.
• Either Database Control or the DBMS_SCHEDULER API can be used to
manage the Scheduler environment.
Use a Time-Based or Event-Based Schedule
for Executing Scheduler Jobs
• A time-based schedule has start and end dates, and a repeat interval.
• The repeat interval can be a date expression, or a calendaring expression
consisting of a frequency, an interval, and possibly several specifiers.
• An event-based schedule uses an agent to query an Advanced Queue, and
launches jobs depending on the content of the queued messages.
Create Lightweight Jobs
• A lightweight job has less overhead in the data dictionary than a regular job,
and therefore large numbers of them can be created much faster than an
equivalent number of regular jobs.
• Lightweight jobs do not have the full range of attributes that regular jobs
have.
Use Job Chains to Perform a Series of Related Tasks
• A chain object consists of a number of steps.
• Each step can launch a program.
• Simple logic (such as the success or failure of a previous step) can control the
flow of execution through a job chain with branching steps.
Create Windows and Job Classes
• A window is a defined period during which certain jobs may run, that will itself
open according to an embedded schedule or a preexisting schedule object.
• A window can activate a Resource Manager plan.
• Only one window can be open at once.
• If windows overlap, the open window will be determined by which has HIGH
or LOW priority.
• A job class associates the jobs in the class with a Resource Manager consumer
group.
P AR T III
Use Advanced Scheduler Concepts to Prioritize Jobs
• Jobs can be prioritized at two levels: the Resource Manager will allocate
resources via consumer groups to all the jobs in a class, and the class will
prioritize the jobs within it according to the job priority set by the Scheduler.
• Scheduler priority varies between levels 1 to 5 (highest to lowest).
Self Test
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