Avoid GROUP BY Mistakes with WINDOW FUNCTION in SQL

I wish I knew this earlier in SQL. It would have saved me hours of confusion. Most beginners use GROUP BY for everything. But that’s a mistake. Because GROUP BY: → Removes your original data → Limits your analysis WINDOW FUNCTION does the opposite. They let you: - Keep all rows - Add calculations on top - Analyze data like a pro For example: ✔️ Running totals ✔️ Ranking ✔️ Comparing past vs current values All without losing your dataset. 👉 Once you understand this, SQL starts to feel easy. 👉 Save this — you’ll need it when practicing. Follow for more simple data concepts. Aman kr Singh LinkedIn #DataAnalytics #SQL #DataAnalyst #LearnSQL #Analytics #CareerGrowth #DataScience #LinkedInGrowth

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This is very important. Don’t just scroll — save this. You’ll need it when you actually start practicing SQL 👇

Window functions are one of those concepts that completely change how you think in SQL. Once you stop collapsing data and start layering insights on top of it, analysis becomes much more flexible 🔍 Aman kr Singh

Grouping too early is a tax on your decision making because you lose the context. Window functions let you see the trend and the cause at the same time. This is how you move from reporting facts to solving problems.

Exactly GROUP BY summarizes, window functions analyze. Beginners overuse GROUP BY and lose valuable row-level context. Once you understand window functions, SQL shifts from reporting to real analytical thinking.

This is one of those aha moments every SQL learner needs early Once you get window functions, it’s not just queries anymore it’s real analysis Aman kr Singh

GROUP BY summarizes, window functions explain, that’s where SQL gets powerful. Aman kr Singh

Thanks for sharing it! I have been practicing window functions for the past week but always get stuck when the pattern changes. This is GOLD for those who want to ace SQL interviews.

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