From Excel to SQL

Your Excel file just hit 1,048,576 rows. Your VLOOKUP is returning #N/A. Your pivot table takes four minutes to refresh. There is a better tool — and it takes less than a week to learn.

SQL is the language that powers every database behind every business system you have ever used — your CRM, your ERP, your finance platform, your e-commerce back end. It has been the most in-demand data skill in business for thirty years. And if you already use Excel, you are far closer to understanding it than you think.

From Spreadsheets to SQL teaches you database querying from zero to job-ready — using your existing Excel knowledge as the foundation the whole way through.

This is not a generic SQL tutorial. Every concept is introduced through a direct Excel translation. SELECT is showing columns. WHERE is applying a filter. GROUP BY is building a pivot table. JOIN is what VLOOKUP was always trying to do — but done properly, across millions of rows, in milliseconds.

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WHAT YOU WILL LEARN

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✔ SQL foundations through Excel analogies — SELECT, FROM, WHERE, ORDER BY, and LIMIT explained using filters, sorts, and column selections you already know

✔ Calculated columns and expressions — write SQL formulas that work like Excel's calculated columns, including date math, string manipulation, and conditional CASE logic

✔ GROUP BY and aggregation — replace your pivot tables with SQL that groups, counts, sums, and averages across millions of rows without slowing down

✔ JOINs — the SQL superpower — combine multiple tables properly using INNER JOIN, LEFT JOIN, and FULL JOIN; understand exactly why this beats VLOOKUP on every measure

✔ Subqueries and CTEs — write layered, readable queries using Common Table Expressions that break complex analysis into clear, manageable steps

✔ Window functions — calculate running totals, rankings, moving averages, and period-over-period comparisons that are impossible in Excel without complex array formulas

✔ INSERT, UPDATE, DELETE, and DDL — go beyond reading data to creating tables, inserting records, and building a complete database from scratch

✔ Three complete real-world projects — a Customer Analytics dashboard, an Inventory Reorder Alert system, and a Sales Pipeline report that runs entirely in SQL against a live database

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WHY SQL BEATS EXCEL FOR DATA WORK

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Excel has a hard row limit of just over one million rows. A mid-sized e-commerce business generates that in a single week. SQL databases handle billions of rows with the same query syntax — and they do it in seconds, not minutes.

SQL queries run directly on the source data, inside the database, without exporting, without copying, and without the version-control nightmare of twelve people editing the same spreadsheet. The query is reproducible, shareable, and version-controllable. The result is always fresh. There is no manual refresh.

Companies that use data to make decisions — which is every competitive business in 2025 — expect their analysts, finance professionals, and operations managers to query data directly. SQL is the universal language that makes that possible, regardless of the database system (PostgreSQL, MySQL, SQLite, Snowflake, BigQuery — the syntax transfers).

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HOW THIS BOOK IS STRUCTURED

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The book is built around a single realistic sales dataset that grows in complexity chapter by chapter. You start with simple SELECT queries on the first day and finish writing multi-table analytical queries with window functions and CTEs by the end. Every chapter opens with the Excel equivalent of what you are about to learn — so there is never a moment of confusion about why you are doing what you are doing.

You will work in SQLite — a free, zero-installation database that runs directly on your computer. No cloud account, no subscription, no IT department required. The skills you build transfer directly to PostgreSQL, MySQL, Microsoft SQL Server, and every other major database platform.

By the end of Chapter 4, you will be writing queries that outperform any Excel formula you have ever used — on data of any size, in any scale of organisation.

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WHO THIS BOOK IS FOR

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→ Business analysts and data analysts who export data from a CRM or ERP into Excel every day and want to query it directly at the source instead

→ Finance and accounting professionals who build large multi-sheet Excel models and need faster, more reliable data access

→ Operations and supply chain teams who manage inventory, orders, and logistics data that far exceeds Excel's comfortable working range

→ Marketing professionals who want to build their own customer segmentation and campaign analysis without waiting for a data team

→ Anyone pursuing a career in data analytics, business intelligence, or data engineering — SQL is the single most requested skill in every data job description on the market

No prior database experience required. No programming background needed. If you can use Excel filters and pivot tables, you have everything you need to start writing SQL today.

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ABOUT THE FROM SPREADSHEETS TO CODE SERIES

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From Spreadsheets to SQL is Book 2 of the From Spreadsheets to Code series by Waskey Press — six practical books that teach Python, JavaScript, R, VBA, and AI Tools to Excel professionals who want to extend their capabilities without a computer science degree. Each book starts from Excel, builds to professional-grade technical skills, and delivers results through hands-on real-world projects with zero academic filler.