"Can SQL Do This?" — Escaping Subquery Hell with Window Functions
LAG, LEAD, RANK for month-over-month, rankings, and running totals
"Can SQL Do This?" — Escaping Subquery Hell with Window Functions
Escaping Subquery Hell
"Get me month-over-month growth rate", "Top 3 products in each category", "Cohort retention analysis"...
Ever received these requests and ended up nesting subqueries inside subqueries, inside more subqueries, until you created a query even you couldn't understand? Master Window functions properly, and complex analytical queries become clean and fast.
1. What Are Window Functions? — 1 Minute Explanation
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