Introduction

Why PostgreSQL?

PostgreSQL is the world's most advanced open-source relational database. It is reliable, feature-rich, and standards-compliant. Here is what makes it stand out:

  • Battle-tested -- Used by Apple, Instagram, Spotify, and thousands of other companies in production.
  • Feature-rich -- JSON, full-text search, arrays, window functions, CTEs, and more -- all built in.
  • Standards-compliant -- Follows the SQL standard closely, so what you learn here applies broadly.
  • Free and open source -- No licensing fees, backed by a strong community since 1996.
  • Extensible -- Custom types, operators, index methods, and procedural languages.

The Story

PostgreSQL traces its origins to the POSTGRES project at UC Berkeley, started by Professor Michael Stonebraker in 1986. The project was a research successor to the Ingres database. In 1996, the project was renamed PostgreSQL to reflect its SQL support, and the open-source community took over development.

Today, PostgreSQL is developed by a global community of contributors. Major releases come out annually, each adding significant features while maintaining backward compatibility.

Who Uses PostgreSQL

PostgreSQL powers some of the world's largest applications:

  • Instagram -- stores hundreds of millions of user records.
  • Spotify -- manages music catalog and user data.
  • Apple -- uses PostgreSQL for various internal services.
  • Reddit, Twitch, The Guardian -- all rely on PostgreSQL in production.

It is the default choice for startups and enterprises alike, and the most popular database on platforms like Supabase, Neon, and Railway.

What You Will Learn

This course contains 22 lessons organized into 8 chapters:

  1. SQL Basics -- SELECT queries, filtering with WHERE, sorting, and pagination.
  2. Tables -- Data types, CREATE TABLE, constraints, keys, and ALTER TABLE.
  3. CRUD Operations -- INSERT, UPDATE, DELETE, upsert, and bulk operations.
  4. Joins -- INNER JOIN, LEFT/RIGHT/FULL OUTER JOIN, self joins, and cross joins.
  5. Aggregations -- COUNT, SUM, AVG, GROUP BY, HAVING, ROLLUP, and CUBE.
  6. Subqueries & CTEs -- Nested queries, correlated subqueries, and Common Table Expressions.
  7. Advanced SQL -- Window functions, JSON operations, arrays, and full-text search.
  8. Performance -- Indexes, EXPLAIN ANALYZE, query optimization, and database design.

Each lesson explains a concept, demonstrates it with SQL examples, and gives you an exercise to practice against a live PostgreSQL database running in your browser.

Let's get started.

Next →