Participating in a SQL hackathon was a challenging and eye-opening experience that went far beyond writing SQL queries under time pressure. What initially seemed like a technical competition quickly became a deep exercise in understanding data, making design decisions, and collaborating effectively as a team. The hackathon revolved around a multi-modal physiological dataset , and navigating its complexity taught me lessons that I will carry forward in every data-driven projec

Introduction Tableau interviews are not the same everywhere because the tool sits at the middle of data analysis, visualization, and business intelligence. Some interviews focus on fundamentals, while others focus on performance tuning. To make the interview preparation easier and more structured, this blog will help with a set of questions using a top‑down approach — starting from easier to advanced questions — making it a one‑stop place for frequently asked Tableau intervie

When working with time-series or event-based data, one of the most common questions we ask is: “What changed compared to the previous record?” Example use cases: Time between patient readings Gap between user logins Delay between transactions Sensor data intervals Event latency analysis Healthcare monitoring intervals SQL window functions are designed precisely for this kind of problem. They allow you to perform calculations across a set of related rows without collapsing th