SQL

I’ll be skipping past the standard SQL techniques, assuming we’re all familiar with the basics because in today’s data-driven world, mastering advanced SQL isn’t just useful for day-to-day analysis, it’s crucial for standing out in live-coding interviews, where you’re expected to navigate and manipulate complex datasets quickly and confidently. 1️⃣ GROUP BY vs. DISTINCT vs. Window Functions Feature GROUP BY DISTINCT Window Functions Use Case Aggregates Removes duplicates Ranking, cumulative sums Performance Medium Fast Can be slow with large data Example: Count unique customers per region. ...