Introduction to Relational Databases
Relational databases organize data into tables with rows and columns, enforcing relationships through keys. They follow the ACID properties: Atomicity, Consistency, Isolation, and Durability, ensuring reliable transactions.
Key features include: - Structured schema with predefined tables and columns. - SQL (Structured Query Language) for querying and managing data. - Normalization to reduce redundancy.
Example: In an e-commerce system, a users table might store customer info, linked via foreign keys to an orders table. Querying with SQL like SELECT * FROM orders WHERE user_id = 123; retrieves a user's purchase history efficiently.
This structure suits applications needing complex joins and data integrity, such as banking systems where transactions must be atomic.