SQL Window Functions Explained | Real-World Examples for Data Engineers скачать в хорошем качестве

SQL Window Functions Explained | Real-World Examples for Data Engineers

SQL window functions are one of the most important — and most misunderstood — topics in SQL. In this video, I explain SQL window functions from a real data engineering perspective, not textbook theory. We use a real-world dataset and solve practical problems that appear in production systems and interviews. You’ll learn: When to use window functions vs GROUP BY How to identify problems that require window functions Running totals, ranking, and latest-record patterns ROW_NUMBER vs RANK vs DENSE_RANK Using LAG to compare rows Common interview patterns used by top companies This video is ideal for: Data engineers SQL developers Analysts moving into data engineering Interview preparation (mid → senior level) No unnecessary theory — only practical SQL you’ll actually use.