Practical SQL

A beginner's guide to SQL built around real public datasets rather than toy tables. It starts with creating and querying tables, then works through joins, aggregation, subqueries, common table expressions and window functions using census, taxi trip and food inspection data. Later chapters cover importing and exporting data, full text search, basic spatial queries with PostGIS, and automating a task on a schedule, all in PostgreSQL. The examples are the kind of analysis a product person actually needs, including rankings, rates per head of population and change over time. Written so you can follow along with a laptop and a free database.