RelationalDBDesign





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Lesson 1

Introduction to Object Relational Database Management Systems

Professional DBAs that have worked with real-world business applications may think, how does the object-relational approach within Oracle8i work?
Oracle8i is an object-relational database management system (ORDBMS), which means that users can define additional kinds of data, specifying both the structure of the data and the ways of operating on the data and use these types within the relational model. This approach adds value to the data stored within a database.
User-defined data types make it easier for application developers to work with complex data such as images, audio, and video. Object types store structured business data in its natural form and allow applications to retrieve it that way. For this reason, they work efficiently with applications developed using oject-oriented programming techniques.
The object-relational model allows users to define new sets of data types and models drawn from the object programming languages. This means you can create persistent objects within the database and access them through an API (application programming interface) from C++, Java, and other programming languages. This object-relational approach specifies both the structure of the data and the methods of operating on the data. We will look at the details of defining methods later in the course.
In the next lesson, we will begin by explaining the reasons to use Oracle objects.


  1. Object-relational: The object-relational model allows users to define object types, specifying both the structure of the data and the methods of operating on the data, and to use these datatypes within the relational model.
  2. Persistent object: An object that is stored or saved. Within Oracle, an object is stored within the database.
Module objectives
When you have completed this module, you will be able to:
  1. Understand the reasons to use Oracle objects versus relational tables
  2. Understand the different terms for Oracle objects
  3. Describe the Structured Query Language (SQL) techniques that allow you to query object tables
  4. Determine when to use collections and variable size arrays
  5. Determine when to use nested tables in querying
  6. Write SQL to query object tables