7 Window Functions MASTERED in 17 Minutes | SQL Masterclass

⚡️Free SQL Course & Datasets Below ⬇️ Free 5-Day Data Career Kickstart: https://www.bigdataenergycourses.com/... Intermediate Course: https://www.bigdataenergycourses.com/... In this video, I teach you the seven essential SQL window functions that every data professional needs to master for interviews. I cover ROW_NUMBER, RANK, DENSE_RANK, SUM, AVERAGE, LEAD, and LAG with real-world examples that show how to solve common business problems like ranking employees, calculating running totals, and comparing data across time periods. By the end of this 15-minute tutorial, you'll understand not just how these functions work, but when and why to use them in actual data scenarios. Chapters: 00:00 - Why window functions matter for data interviews 00:50 - What window functions are and how they work 01:53 - ROW_NUMBER function with sales data 03:55 - RANK function and handling ties 05:38 - DENSE_RANK function differences 06:56 - Adding PARTITION BY to ranking functions 08:00 - SUM window function for running totals 10:22 - AVERAGE window function for rolling averages 12:33 - LEAD and LAG functions for time comparisons 16:31 - Next steps for interview preparation 🤳🏼 SOCIALS 📫 Newsletter: https://jessramosdata.substack.com/ 📸 Instagram: @JessRamosData 💙 LinkedIn: Jess Ramos, MSBA 🎬 TikTok: @JessRamosData 💌 Brand Partnerships: [email protected]