ZS Associates Interview Question

They asked a mix of SQL questions — things like using RANK() for ranking rows, combining HAVING with GROUP BY for filtering aggregates, and writing different types of JOIN queries. One question was about deleting duplicates using window functions like ROW_NUMBER(). They also threw in a few guesstimate and scenario-based questions. For example, I had to estimate the number of traffic lights in my city by breaking it down from population to intersections, and answer a scenario where I had to explain how I’d handle a situation where in my work I am seeing consistently a 20% loss in data storing or data collection .