SQL Fundamentals

Sometimes when you spend too much time in the frontend or ops world, you need to remind yourself of the power and importance of proper database design and querying. SQL is the foundation of most applications, and understanding it deeply can make the difference between a performant application and one that struggles under load.

This series focuses on PostgreSQL, one of the most powerful and feature-rich open-source databases available. Whether you're building a simple CRUD application or a complex data warehouse, PostgreSQL has the tools you need.

Why PostgreSQL?

PostgreSQL is more than just a database—it's a complete data management system. It supports:

  • ACID Compliance: Full transaction support with rollback capabilities
  • Advanced Data Types: JSON, arrays, geometric types, and custom types
  • Extensibility: Custom functions, operators, and data types
  • Performance: Sophisticated query planner and multiple indexing strategies
  • Scalability: Built-in replication, partitioning, and clustering

What We'll Cover

  1. PostgreSQL Indices - Understanding when and how to use different types of indices
  2. SQL Joins - Mastering the art of combining data from multiple tables
  3. Query Optimization - Writing efficient queries and understanding execution plans
  4. Transactions and Concurrency - Managing data consistency in multi-user environments
  5. Advanced Data Types - Leveraging PostgreSQL's rich type system
  6. Window Functions - Performing complex analytical queries
  7. Common Table Expressions - Writing readable and maintainable complex queries
  8. Performance Tuning - Monitoring and improving database performance

Getting Started

Before diving into the articles, make sure you have PostgreSQL installed and running. You can download it from the official website or use Docker:

docker run --name postgres -e POSTGRES_PASSWORD=mysecretpassword -p 5432:5432 -d postgres

The Database Mindset

Working with databases requires a different mindset than frontend development. While frontend development often focuses on user experience and immediate feedback, database work requires:

  • Performance thinking: Every query should be optimized
  • Data integrity: Ensuring consistency across all operations
  • Scalability planning: Designing for growth from the start
  • Analytical thinking: Understanding how data relates and flows

Let's dive in and rediscover the power of SQL!