Book Image

Oracle Advanced PL/SQL Developer Professional Guide

By : Saurabh K. Gupta
Book Image

Oracle Advanced PL/SQL Developer Professional Guide

By: Saurabh K. Gupta

Overview of this book

PL/SQL (Procedural Language/Structured Query Language) is Oracle Corporation's procedural extension language for SQL and the Oracle relational database. Server-side PL/SQL is stored and compiled in the Oracle Database and runs within the Oracle executable. With this guide Oracle developers can work towards accomplishing Oracle 11g Advanced PL/SQL Professional certification, which is the second milestone for developers working at the Associate level. The Oracle Advanced PL/SQL Developer Professional Guide helps you master advanced PL/SQL concepts. Besides the clear and precise explanation on advanced topics, it also contains example code and demonstrations, which gives a sense of application and usage to readers.The book gives a deep insight that will help transform readers from mid-level programmers to professional database developers. It aims to cover the advanced features of PL/SQL for designing and optimizing PL/SQL code.This book starts with an overview of PL/SQL as the programming database language and outlines the benefits and characteristics of the language. The book then covers the advanced features that include PL/SQL code writing using collections, tuning recommendations using result caching, implementing VPD to enforce row level security, and much more. Apart from programming, the book also dives deep into the usage of the development tool SQL Developer, employing best practices in database environments and safeguarding the vulnerable areas in PL/SQL code to avoid code injection.
Table of Contents (22 chapters)
Oracle Advanced PL/SQL Developer Professional Guide
Credits
Foreword
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

VPD implementation—outline and components


The development steps of VPD implementation is demonstrated in the flowchart as follows:

  • Creation of an application context: The application context is a collection of variables whose values, once set, remain the same and are available in the same session. The variables are known as attributes. Each session accessing the same application context attributes can have different values.

  • Create the context key and value: Create the trusted program to set the context using DBMS_SESSION.SET_CONTEXT. During the creation of the context, Oracle does not verify the existence of the program being specified. It relies on the trust of the user to create and use a program with the same name to set the context attributes. Therefore, the program is referred to as trusted.

  • Set the context key explicitly or through a Logon trigger: The context must be set for the whole session or just before each call. System-level Logon triggers are also capable of scheduling...