Database Management Systems

Types of Database Management Systems

The main Four Types of Database Management Systems are:

• Hierarchical database

• Network database

• Relational database

• Object-Oriented database

Hierarchical

In a Hierarchical database model, data is arranged in a hierarchical or tree-like structure, and stored either top-down or bottom-up format. The organization of data is based on a parent-child relationship, where parents can have multiple children, while children can have only one parent.

Network

In the network model, each child can have multiple parents. This model is particularly useful for representing complex relationships, such as the many-to-many relationship between orders and parts. The entities are organized in a graph structure, enabling access through multiple paths. This flexibility allows for efficient navigation and retrieval of data by establishing various connections between entities.

Relational

The Relational DBMS is extensively utilized due to its user-friendly nature, making it one of the most popular database management models. It is built on the concept of organizing data into normalized tables with rows and columns. In the Relational model, data is stored in structured formats and can be efficiently manipulated using SQL (Structured Query Language)

Object-Oriented

The Object-oriented Model stores data in the form of objects. The structure is defined as classes that encapsulate data within them. This model is a fundamental component of DBMS, where a database is seen as a collection of objects that store both data member values and associated operations. Such databases use an object-oriented programming language for development.

RDBMS is the basis for Structured Query Language, and for all modern database systems like MS SQL Server, IBM DB2, Oracle, MySQL, Postgres, etc.

NoSQL (Not Only SQL) or Non-Relational databases

A popular alternative to relational databases, NoSQL databases take a variety of forms and allow you to store and manipulate large amounts of unstructured and semi-structured data. Examples include key-value stores, document stores and graph databases.

Types of NoSQL Databases:

• Column-oriented Graph

• Graphs based

• Document-oriented

• Key-value Pair Based

Relational Database	NoSQL
It is used to handle data coming in low velocity.	It is used to handle data coming in high velocity.
It gives only read scalability.	It gives both read and write scalability.
It manages structured data.	It manages all type of data.
Data arrives from one or few locations.	Data arrives from many locations.
It supports complex transactions.	It supports simple transactions.
It has single point of failure.	No single point of failure.
It handles data in less volume.	It handles data in high volume.
Transactions written in one location.	Transactions written in many locations.
Support ACID properties compliance	Doesn’t support ACID properties
Its difficult to make changes in database once it is defined	Enables easy and frequent changes to database
Schema is mandatory to store the data	Schema design is not required
Deployed in vertical fashion.	Deployed in Horizontal fashion.

Some of the Popular DBMS Softwares

Proprietary

• Microsoft Access

• Microsoft SQL Server

• Oracle

• IBM DB2 (free plan option)

• dBASE

Open Source

• MySQL (Enterprise plan available)

• PostgreSQL

• SQLite

• MariaDB

• Altibase

• LibreOffice Base

• Cubrid

• MongoDB (NoSQL / document-oriented)

• Cassandra (NoSQL)

Applications of Database

Field	Application
Airline	Flights, reservations, schedules, tickets, etc.
Banking	Clients, account activities, loans, balances etc.
Library	Book information, borrower information, issue date, etc.
Education	Student information, courses, departments, grades, etc.
Telecommunication	Call records, usage, bills, balances etc.
Social Media	User data, demographics, preferences, etc.
E-Commerce	Customer data, purchases, invoices, etc.
Human Resources	Employee information, salary, payroll, deductions, etc.
Manufacturing	Supplier information, product details, quantities, etc.