🚀 4 Window Functions Jo Har Backend Developer Ko Pata Hone Chahiye! Pehle purane tareeke se struggle karte the — self joins, multiple queries, temp tables… Ab ye 4 functions seekh lo toh life set hai: 1️⃣ ROW_NUMBER(), RANK(), DENSE_RANK() 2️⃣ LAG() & LEAD() — pichla/next value compare karne ke liye 3️⃣ Running Total with SUM() OVER() 4️⃣ PARTITION BY — group-wise magic Ek baar samajh aa gaya toh bahut saare complex queries ek line mein ho jayenge! 💯 Kaunsa function pe detailed video chahiye? Comment mein batao 👇 Follow @DevNotes_io for more real SQL & Backend tips! #SQL #WindowFunctions #BackendDeveloper #SQL #WindowFunctions #SQLTips #PostgreSQL #MySQL #BackendDeveloper #Database #TechHindi #CodingTips #DeveloperLife #SQLPerformance #DataEngineering #DevNotesIO

Never use SELECT * in production queries ?

SQL Query running slow? Here's how I tuned a 10x slower query in production. Common mistake: SELECT * with unnecessary JOINs. Fix 1: Use EXPLAIN ANALYZE Fix 2: Proper indexing on WHERE/GROUP BY columns Fix 3: Avoid functions on indexed columns What’s your biggest SQL performance headache? Drop it below 👇 #SQL #Database #Backend #DevNotes

PrepSQL is live. Practice SQL with lessons, quizzes, daily challenges, company-style questions, progress tracking, and AI mock interviews. LINK : play.google.com/store/apps/d… Built for SQL learners and interview prep. Would love your support and feedback. #education #developer #computerscience