Articles Cookbook
18 Mar 2026
LearnSQL.com Team

ETL vs ELT – What SQL Analysts Need to Know

Modern data pipelines often rely on two approaches: ETL and ELT. The difference between them affects where data is cleaned, how transformations run, and how much SQL analysts participate in building the pipeline. Understanding this shift helps you see how raw data becomes analysis-ready tables in today’s data warehouses. If you work with data, you’ve likely seen the terms ETL and ELT. Both describe how data moves from a source system (such as an application database) to a destination like a data warehouse or dashboard.
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11 Mar 2026
LearnSQL.com Team

How to Use AI to Learn SQL Faster – A Beginner’s Guide

AI can explain SQL concepts, generate examples, and help debug queries. But using it well is what makes the difference. In this guide, you’ll learn how beginners can combine AI tools with structured courses and hands-on practice to learn SQL faster. You’ve decided to master SQL. You’ve watched the tutorials, bookmarked the cheat sheets, and finally typed your first SELECT *. At first, it feels like magic. Then, the honeymoon phase ends.
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4 Mar 2026
LearnSQL.com Team

The Best SQL Projects to Start Your Portfolio this Spring (With Dataset Ideas)

Want to turn your SQL skills into something you can actually show recruiters this spring? In this article, you’ll find practical SQL portfolio project ideas with real dataset suggestions, so you can move beyond exercises and build work that proves your skills – especially after finishing structured courses like those on LearnSQL.com. Spring is a natural reset point. In ancient Rome, spring marked the beginning of the year. The earliest Roman calendar started in March.
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1 Mar 2026
Jakub Romanowski

Course of the Month: Window Functions in PostgreSQL

Are you looking for the best way to master SQL window functions? Throughout March 2026, you can access the interactive course Window Functions in PostgreSQL for free. Boost your skills at no cost. Hurry, time is running out! Need a free PostgreSQL course on window functions? You've come to the right place! If you are reading this article, you probably know PostgreSQL is one of the most popular databases in the world.
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25 Feb 2026
LearnSQL.com Team

Your 90-Day Plan to Learn the SQL Skills Hiring Managers Want in 2026

Want to get job-ready SQL skills in three months? This 90-day plan shows you exactly what to learn, when to practice, and how to build projects that hiring managers care about. Follow the steps, stay consistent, and you’ll be ready for real SQL interview tasks in 2026. If you look at SQL job listings today, you’ll notice something interesting. The tools change, cloud platforms evolve, dashboards look different, but the core SQL skills employers expect stay surprisingly consistent.
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18 Feb 2026
Scott Davis

The SQL Metrics Interviewers Really Care About (From Real Interviews)

After a few SQL interviews, it’s easy to assume every company tests something different. After 11 of them, that assumption stopped holding up. Despite differences in companies and formats, the same metric questions kept coming back. This article summarizes what I saw most often and what those patterns say about how SQL interviews really work. Between November 2023 and April 2025, I took part in 11 data analyst interviews that included SQL technical screens.
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11 Feb 2026
LearnSQL.com Team

The Perfect Match: SQL Joins Explained

Not every invitation leads to a perfect match — and the same is true in SQL. This article explains SQL JOINs using a party guest list example, helping you understand how different JOIN types decide which records appear in the result. February is the month of love. Dating apps talk about matches, invitations go out for Valentine’s events, and everyone hopes things line up the right way. In SQL, we deal with matching all the time — just in a more practical way.
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4 Feb 2026
LearnSQL.com Team

Building a Custom 'Recommendation Engine' in 10 Lines of SQL

Recommendation engines don’t always start with AI or machine learning. In many cases, a few well-written SQL queries are enough to uncover products that customers frequently buy together. In this article, you’ll build a simple recommendation engine in about 10 lines of SQL using self-joins and aggregation. When you hear “recommendation engine,” you probably think of machine learning, Python notebooks, and complex AI models. That association has become so common that we often forget how many recommendations in real systems are built on much simpler foundations.
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1 Feb 2026
Jakub Romanowski

Free Course of the Month: Customer Behavior in MySQL

Have you ever wondered how businesses really get to know their customers? It’s all about analyzing behavior and, if you’re working with MySQL, there’s an awesome free course on LearnSQL.com that shows you how to do just that. Let me tell you all about it! If you’ve got the basics of MySQL down and want to dig into customer behavior analysis, you’re in luck! LearnSQL.com has a free course this month just for you—Customer Behavior Analysis in MySQL.
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28 Jan 2026
Agnieszka Kozubek-Krycuń

How to Read a Database Schema and Know What to Query

SQL queries are rarely the problem. The real challenge is opening a new database and knowing where the data you need actually lives. This article shows how to read a database schema so you can quickly understand what to query and where to start. My husband claims that the hardest part of using SQL in practice isn’t writing queries. For him, the real challenge is opening a database he’s never seen before and figuring out where things are.
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