Database Series: From Fundamentals to Scale
Databases are the backbone of every scalable system.
Whether you’re preparing for high-level design (HLD) interviews or building real-world distributed systems, understanding how databases work — and how they scale — is essential.
This series is structured to take you from basics → advanced → real-world case studies, so you can follow it like a course or jump directly to the topic you need.
Articles in This Series
1. Fundamentals
- Database Fundamentals
Basics of relational vs non-relational databases, ACID vs BASE, and core terminology. - SQL vs NoSQL
Deep dive into relational vs non-relational models, use cases, and trade-offs. - CAP Theorem & Consistency Models
Understanding consistency, availability, and partition tolerance in distributed systems. - Database Indexing
How indexes speed up queries, different indexing techniques, and common pitfalls. - Sharding vs Replication
Core scaling strategies, when to use them, and their trade-offs.
2. Scaling & Advanced Techniques
- Database Scaling Patterns
Vertical vs horizontal scaling, replication strategies, and sharding techniques. - Specialized Databases
Key-Value, Document, Wide-Column, Graph, Search, and Time-Series databases explained. - Caching & Query Optimization
How caching works, caching strategies, and query optimization best practices. - Distributed Transactions & Patterns
2PC, 3PC, Saga pattern, CQRS, and Event Sourcing.
3. Real-World & Interviews
- Polyglot Persistence & System Design Patterns
Using multiple databases in a single system — real-world strategies. - Case Studies
How Instagram, WhatsApp, Netflix, and Uber solved database scaling challenges. - Interview Guide: Databases in HLD
How to approach database design in system design interviews, pitfalls, and checklists.
4. Deep Dive: Internals
- Database Internals
Write-ahead logs, MVCC, B-Trees, LSM trees, consensus (Raft, Paxos), consistent hashing, and bloom filters.
How to Use This Series
- Beginner? Start from Fundamentals (Articles 1–5).
- Interview Prep? Focus on CAP, Scaling, Indexing, and Interview Guide.
- Real-world Engineer? Jump into Scaling Patterns, Transactions, Case Studies, and Internals.
Further Reading
- Designing Data-Intensive Applications — Martin Kleppmann
- System Design Interview — Alex Xu
- High Scalability Blog
- Engineering blogs of Netflix, Uber, Airbnb, and Meta