You 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?
~4 min by voice
How to approach it
This checks whether you can do more than draw an SCD2 table, and actually build a reliable incremental process: a correct MERGE, idempotent reruns, late-arriving data, lost intraday changes and correctly tying facts to versions.
The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.