SQL for Data Analysis - Foundations

SQL is one of the most useful skills for anyone who works with data. It lets you go directly to the source, pull the data you need, check assumptions, join tables, calculate metrics, and build outputs you can trust.

SQL for Data Analysis: Foundations is a practical ebook for analysts, finance professionals, business users, and students who want to learn SQL for analytical work.

The focus is on the kind of SQL that analysts use every day: pulling data, filtering and slicing, joining tables, building summaries, and writing queries that answer real business questions.

A sample database and all practice files are included so you can follow along and run every query yourself. The SQL patterns you learn here carry over to PostgreSQL, MySQL, BigQuery, Snowflake, and SQL Server.

What You Will Learn

• How relational databases are structured
• How to write SELECT queries and filter, sort, and limit results
• How to group data and calculate summary metrics
• How to join tables without accidentally multiplying rows
• How to use subqueries and common table expressions (CTEs)
• How to write window functions for rankings, running totals, and comparisons
• How to work with dates, timestamps, text fields, and NULL values
• How to clean and validate data before using it in analysis
• How to read query plans and understand basic indexing

How The Book Works

The book starts with setup and your first query, then builds chapter by chapter. Each chapter introduces a small set of concepts, shows runnable SQL examples, explains what the result means, and ends with practice exercises.

The included database lets you follow along immediately. A Markdown query companion gives you clean SQL blocks so you do not have to copy queries from the PDF.

Who This Is For

• You are new to SQL and want a practical learning path
• You work with spreadsheets, dashboards, or reports and want to query data directly
• You are an analyst or finance professional who wants stronger data skills
• You know a little SQL but want to become more confident with joins, grouping, CTEs, and window functions

You do not need prior database experience.