Book Image

Advanced Oracle PL/SQL Developer's Guide (Second Edition) - Second Edition

By : Saurabh K. Gupta
Book Image

Advanced Oracle PL/SQL Developer's Guide (Second Edition) - Second Edition

By: Saurabh K. Gupta

Overview of this book

Oracle Database is one of the most popular databases and allows users to make efficient use of their resources and to enhance service levels while reducing the IT costs incurred. Oracle Database is sometimes compared with Microsoft SQL Server, however, Oracle Database clearly supersedes SQL server in terms of high availability and addressing planned and unplanned downtime. Oracle PL/SQL provides a rich platform for application developers to code and build scalable database applications and introduces multiple new features and enhancements to improve development experience. Advanced Oracle PL/SQL Developer's Guide, Second Edition is a handy technical reference for seasoned professionals in the database development space. This book starts with a refresher of fundamental concepts of PL/SQL, such as anonymous block, subprograms, and exceptions, and prepares you for the upcoming advanced concepts. The next chapter introduces you to the new features of Oracle Database 12c, not limited to PL/SQL. In this chapter, you will understand some of the most talked about features such as Multitenant and Database In-Memory. Moving forward, each chapter introduces advanced concepts with the help of demonstrations, and provides you with the latest update from Oracle Database 12c context. This helps you to visualize the pre- and post-applications of a feature over the database releases. By the end of this book, you will have become an expert in PL/SQL programming and will be able to implement advanced concepts of PL/SQL for efficient management of Oracle Database.
Table of Contents (19 chapters)
Advanced Oracle PL/SQL Developer's Guide Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

What is SQL injection?


A database application on the server side contains the programmable logic embedded within the PL/SQL packages and subprograms. These PL / SQL program units may contain SQL statements, which are intended to perform specific operations. The SQL statements, whose query text is built at runtime (dynamically derived) and based on client-supplied inputs, open ways for SQL injection. A malicious user can supply a manipulated input that can break through the PL/SQL program logic by replacing the SQL syntax and perform arbitrary execution.

The reason it is known as Injection is because the manipulated text, which replaces or appends to the original SQL text in a PL/SQL program unit, is parsed along with the original SQL statement. The undetected attacker's code is legally executed by the SQL engine, along with the original programmed SQL.

For example, a string type malicious input from the client is executed as legal code by the SQL engine; thus, exploiting a server-side SQL...