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


This chapter gave you a quick look at the two basic types of events that play a role in the Scheduler: the event generated by status changes in a running job and the event that causes a job to run. Both are very important factors in the power of the Scheduler. The objects that we have discussed in the chapter are:

  • How we can schedule time-based and event-based jobs

  • How jobs can generate events

  • How jobs can wait for events to get the job running

  • How to listen to events

  • How to generate events

  • How to get the payload of an event (de-queue)

  • How to find the step name that caused the event to happen

  • Why we need quota when using a user event queue

  • What privileges we need to be able to use scheduler events

  • What is the advantage of monitoring jobs using the event system

  • Which events a job can cause

  • How to write a short form containing all possible events

Scheduler is an impressive tool that enables us to build complex systems. In the next chapter, we will see a few tricks to help you when debugging it...