DBMS is a collection of programs used for managing data and simultaneously it supports different types of users to create, manage, retrieve, update and store information.
The types of DBMS based on data model are as follows −
Object oriented database.
A relational database management system (RDBMS) is a system where data is organized in two-dimensional tables using rows and columns.
This is one of the most popular data models which is used in industries. It is based on SQL.
Every table in a database has a key field which uniquely identifies each record.
This type of system is the most widely used DBMS.
Relational database management system software is available for personal computers, workstation and large mainframe systems.
For example − Oracle Database, MySQL, Microsoft SQL Server etc.
In the above student table Std ID, Name and city are called as attributes and their values. Std ID is a primary key attribute which uniquely identifies each record in the student table.
It is a system where information or data is represented in the form of objects which is used in object-oriented programming.
It is a combination of relational database concepts and object-oriented principles.
Relational database concepts are concurrency control, transactions, etc.
OOPs principles are data encapsulation, inheritance, and polymorphism.
It requires less code and is easy to maintain.
For example − Object DB software.
The object oriented database is represented in diagram format below −
It is a system where the data elements have a one to many relationship (1: N). Here data is organized like a tree which is similar to a folder structure in your computer system.
The hierarchy starts from the root node, connecting all the child nodes to the parent node.
It is used in industry on mainframe platforms.
For example− IMS(IBM), Windows registry (Microsoft).
An example of a hierarchical database is given below −
A Network database management system is a system where the data elements maintain one to one relationship (1: 1) or many to many relationship (N: N).
It also has a hierarchical structure, but the data is organized like a graph and it is allowed to have more than one parent for one child record.
Teachers can teach in multiple departments. This is shown below −