OCA /OCP Oracle Database 11g A ll-in-One Exam Guide- P88:There is an ever increasing demand for staff with IT industry certification. The benefits to employers are significant—they can be certain that staff have a certain level of competence—and the benefits to the individuals, in terms of demand for their services, are equally great. Many employers are now requiring technical staff to have certifications, and many IT purchasers will not buy from firms that do not have certified staff. | OCA OCP Oracle Database 11g All-in-One Exam Guide 826 10. Tidy up with Database Control connect as SYSTEM. 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. Chapter 22 The Scheduler 827 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
