Question library
Questions from real interviews. Drill any of them by voice in a couple of minutes, with an interviewer, a score and feedback.
What are slowly changing dimensions, SCDs, and what types do you know?JuniorThe warehouse has a customer dimension, and a customer's city and pricing plan can change. Analysts need revenue reports that take into account which plan the customer was on at the time of purchase. How would you store this dimension?Mid-levelYou need to keep a history of changes to customer attributes, such as plan, city and segment, in a data warehouse, loading data incrementally once a day. How would you implement a Type 2 SCD, and what pitfalls have you run into?Senior