Databases

A database is an organized collection of data that is stored and accessed electronically. It allows for efficient retrieval, insertion, updating, and management of data.

Types of Databases

1. Relational Databases (RDBMS)

• Store data in tables (rows and columns)
• Use SQL (Structured Query Language)
• Examples: Microsoft SQL Server, Oracle, MySQL, PostgreSQL

2. NoSQL Databases

• Designed for high scalability and flexible schema
• Four main types:
• Document-based: MongoDB, CouchDB
• Key-Value stores: Redis, DynamoDB
• Column-based: Cassandra, HBase
• Graph-based: Neo4j, Amazon Neptune

Databases are used everywhere in technology to store, manage, and retrieve data efficiently.

Primary Uses of Databases

1. Data Storage
Store structured (SQL) or unstructured (NoSQL) data Centralized and organized repository Supports large volumes of data (e.g., terabytes or petabytes)

2. Data Retrieval & Querying
Efficient search, filtering, sorting, and joining of data
Enables reports, dashboards, and analytics.

Use of query languages like SQL, MongoDB Query Language, etc.

Use in Applications

• Web Applications: Store user data, logins, form entries (MySQL, MongoDB)
• Mobile Apps: Local and cloud sync data (Firebase, Realm)
• Enterprise Systems: ERP, CRM, HRM platforms (Oracle, MS SQL Server)
• Cloud Services: Scalable, managed databases (Amazon RDS, MongoDB Atlas)
• Analytics/BI Tools: Dashboards powered by real-time or batch data (PostgreSQL, BigQuery)