Introduction to DBMS

In today's digital world, data is one of the most valuable assets. Every application you interact with, from social media platforms to online banking, relies on structured data storage and efficient management. This is where a Database Management System (DBMS) comes into play, serving as the foundation for handling and organizing vast amounts of data efficiently.

Data refers to raw facts, numbers, characters, or symbols that have no inherent meaning on their own. For example, the number '1', the string "Prince", and the character 'a' are all considered data.

Information is derived from processed data, providing facts and insights. For example, the name "Prince" is just data. However, when someone says, "This is Prince" it becomes information because it carries meaning and context.

What is a Database?

A database is an organized collection of data that allows users to store, retrieve, and manage information systematically. Imagine a library where books are categorized into sections, making it easy to find a specific book. Similarly, a database organizes data into tables, ensuring fast and structured access.

Real-World Uses of Databases:

• Websites like Amazone store product details, customer data, and order history in databases.
• Banks manage account details, transactions, and customer records through databases.
• Platfrom like Facebook and Instagram store user profiles, posts, and interactions in databases.

What is a File System?

A file system is a method of storing raw data in an unstructured manner. This means data is stored in separate files without predefined organization, making retrieval inefficient as the volume of data increases. file systems fail because initially used to store data, but as applications grew in complexity, they encountered several challenges like:

• The same data was stored multiple times, wasting storage space.
• If one version of a file was updated but another was not, conflicting data would arise.
• File systems lacked sophisticated access control mechanisms.
• Multiple users accessing and modifying files simultaneously led to conflicts.
• As data grew, organizing and retrieving it became slow and inefficient.

What is a DBMS?

A Database Management System is software that enables users to create, manage, and interact with databases efficiently. Unlike traditional file systems, DBMS provides a structured approach to storing and managing data, ensuring better security, integrity, and performance.

Before databases existed, organizations relied on file systems to store data. However, this approach led to inefficiencies such as data redundancy, inconsistency, and security vulnerabilities. Database Management Systems addressed these challenges by offering:

• Efficient data management for organizing data systematically for easy retrieval and storage.
• Data integrity and security for ensuring data consistency and restricting unauthorized access.
• Concurrency control for allowing multiple users to access the database simultaneously without conflicts.
• Backup and recovery for providing mechanisms to restore data in case of system failure

DBMS vs File System

Feature	File System	DBMS
Data Organization	Stored as separate files	Structured into tables with relations
Redundancy	High (data duplication)	Low (normalization prevents duplication)
Security	Basic file-level permissions	Advanced access control, authentication
Data Integrity	Hard to maintain	Ensured through constraints and relationships
Concurrency	Difficult to manage	Efficiently handled by DBMS
Querying	Manual search needed	Uses SQL for efficient querying

Types of Databases

Different types of databases are suited for specific applications based on factors like data structure, scalability, and performance needs.

1. Relational Databases (RDBMS)

Relational databases store data in tables, where each row represents a record and each column represents an attribute. They follow a strict schema and use SQL (Structured Query Language) for queries. Popular relational databases include MySQL, PostgreSQL, Oracle, and Microsoft SQL Server, widely used by organizations today.

Online banking systems rely on RDBMS to manage customer accounts, transactions, and loan details while ensuring data consistency and security.

2. NoSQL Databases

NoSQL databases store data in various formats such as key-value pairs, documents, wide-columns, or graphs, making them more flexible for unstructured data. Common NoSQL databases include MongoDB (document-based), Cassandra (wide-column), Redis (key-value), and Neo4j (graph-based).

Social media platforms like Instagram use NoSQL databases to handle millions of user interactions per second, ensuring high scalability and performance.

3. NewSQL Databases

NewSQL databases combine the scalability of NoSQL with the structured querying capabilities of traditional RDBMS, making them suitable for high-performance applications. Examples include Google Spanner, CockroachDB, and YugabyteDB.

Global e-commerce platforms leverage NewSQL databases to maintain high availability and process real-time transactions across different regions.

Popular DBMS Software

Some widely used database management systems include:

DBMS	Type	Best For
MySQL	RDBMS	Web applications, startups
PostgreSQL	RDBMS	High-performance systems, analytics
MongoDB	NoSQL	Flexible, scalable document storage
Oracle DB	RDBMS	Enterprise-level applications
Cassandra	NoSQL	Distributed big data storage
Redis	NoSQL	Caching, real-time data processing