Book Image

Mastering Oracle Scheduler in Oracle 11g Databases

By : Ronald Rood
Book Image

Mastering Oracle Scheduler in Oracle 11g Databases

By: Ronald Rood

Overview of this book

Scheduler (DBMS_SCHEDULER) is included in Oracle Database and is a tool for the automation, management, and control of jobs. It enables users to schedule jobs running inside the database such as PL/SQL procedures or PL/SQL blocks, as well as jobs running outside the database like shell scripts. Scheduler ensures that jobs are run on time, automates business processes, and optimizes the use of available resources. You just need to specify a fixed date and time and Scheduler will do the rest. What if you don't know the precise time to execute your job? Nothing to worry about, you can specify an event upon which you want your job to be done and Scheduler will execute your job at the appropriate time. Although scheduling sounds quite easy, it requires programming skills and knowledge to set up such a powerful, intelligent scheduler for your project. This book is your practical guide to DBMS_SCHEDULER for setting up platform-independent schedules that automate the execution of time-based or event-based job processes. It will show you how to automate business processes, and help you manage and monitor those jobs efficiently and effectively. It explains how Scheduler can be used to achieve the tasks you need to make happen in the real world. With a little understanding of how the Scheduler can be used and what kind of control it gives, you will be able to recognize the real power that many known enterprise-class schedulers ñ with serious price tags ñ cannot compete with. You will see how running a specific program can be made dependent on the successful running of certain other programs, and how to separate various tasks using the built-in security mechanisms. You will learn to manage resources to balance the load on your system, and gain increased database performance.
Table of Contents (15 chapters)
Mastering Oracle Scheduler in Oracle 11g Databases
About the Author
About the Reviewers

Standby databases

Jobs are mostly defined in a normal primary database. There are reasons for desiring jobs to run in a standby database. Oracle 11g introduces the database roles for this purpose. In the database_role attribute of a job, we can specify when a job should run. Should it run when the database is run in the PRIMARY role, or should it run when the database runs in the LOGICAL STANDBY role? There is no option for the PHYSICAL STANDBY role. It is understandable that the PHYSICAL STANDBY role is not implemented. But at the same time there could be some valid reasons to still want jobs to run with the database in the PHYSICAL STANDBY role. That would, of course, be without the fancy logging, but what about the maintenance of the applied archives? This still has to be scheduled outside the database that needs this maintenance.

Creating jobs in a logical standby database

The job creation in DDL is not propagated to the logical standby database. However, you can create Scheduler jobs...