The SQL Tutorial for Data Analysis

What & Why

SQL is the language for asking a database questions: which users churned, what campaign spend looked like last quarter, and which product features receive the strongest ratings. Unlike a general-purpose programming language, SQL is built around describing what data you want and letting the database decide how to retrieve it.

This track teaches SQL the way a working analyst uses it: reading real Queryflo domain tables, writing queries against them, and building from single-table basics to advanced analytical patterns.

See How It Works

Every lesson follows the same shape: a short explanation, a worked example with actual columns and output, a mistake to watch for, and a practice exercise you solve yourself.

• Foundations — SELECT, FROM, aliases, and DISTINCT
• Filtering, Sorting, and Aggregating — narrowing and summarizing data
• Joins, Subqueries, and CTEs — combining and structuring complex questions
• Window Functions and Business Metrics — patterns used in real reports and dashboards