The need for a data model that more accurately matched the real world became apparent as real-world problems became more complicated. Both data and the data relationships are stored into a single structure that’s known as an object in the object-oriented data model (or OODM). The object-oriented DMS (or Data Management System) is built on top of the OODM (OODBMS).
In this article, we will dive deeper into the OODM in DBMS according to the GATE Syllabus for (Computer Science Engineering) CSE. Keep reading ahead to learn more.
Table of Contents
What is the OODM in DBMS?
The OODM is a better representation of real-world challenges. Both the data and the relationship are contained into a single structure that’s known as an object in this model. We can now store audios, pictures, videos, and other types of data in databases, which was previously impossible with the relational approach (Although you can store video and audio in relational DB, it is generally advised not to store them in the relational DB).
Examples
Here is an example of this model:
Multiple objects are connected in this model using connections. The following example can help you understand this.
The Employee and Department are the two objects in the example above. Each object’s data and the relationships are there in a single unit. Here, the attributes of the employee, such as Name and Job_title, as well as the methods that will be performed by that object, are all kept in a single object. The two objects are linked by a common attribute, i.e., Department_id, as well as communication between them will be accomplished by this common id.
Components of an Object-Oriented Data Model
• An object is a representation of a physical entity. In general, an object can be thought of as the entity of an ER model. A single instance of an entity is represented by an object. Several of the components in this list define the semantic content of the object.
• An object’s attributes are described by attributes. For example, the properties Social Security Number, Name, and Date of Birth are all present in a PERSON object.
• Classes are groups of objects with similar features. A class is a group of objects that have similar structure (attributes) and behaviour (methods). A class is similar to the entity set in the ER model in general. A class, on the other hand, differs from an entity set. It has a collection of procedures called methods. The method of a class depicts a real-world activity like finding a PERSON’s name, updating a PERSON’s name, printing a PERSON’s address, and many more. In other words, in classical programming languages, the methods are equivalent to procedures. Methods define the behaviour of an object in OO terms.
• A class hierarchy is used to organise classes. The class hierarchy in some ways resembles an upside-down tree with only one parent for each class. The CUSTOMER and EMPLOYEE classes, for example, have the same parent PERSON class. (Notice how this is comparable with the hierarchical data model).
• Inheritance refers to an object’s capacity to inherit the characteristics and methods of those classes that are above it in the class hierarchy. For instance, two classes can be built as subclasses of the PERSON class: CUSTOMER and EMPLOYEE. EMPLOYEE and CUSTOMER will inherit all properties and methods from PERSON in this situation.
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Also Explore,
- Introduction to DBMS
- Data Models in DBMS
- Hierarchical Model in DBMS
- Network Model in DBMS
- Entity-Relationship Model in DBMS
- ER Diagram in DBMS
- ER Diagram to Tables in DBMS
- Object-Relational Data Model in DBMS
- Flat Data Model in DBMS
- Semi-Structured Data Model in DBMS
- Associative Data Model in DBMS
- Context Data Model in DBMS
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