Orphan Attributes with No Natural Home

The Problem Set up the scenario: 'The fact table has is_gift, is_prime, is_expedited, payment_method, and invoice_number. Where do these go? Leaving all five on the fact adds columns that every scan reads even when unused. Creating a dimension for each one is dimension explosion. The answer: consolidate the flags into a junk dimension, keep invoice_number as a degenerate dimension.' Deliver this in 15 seconds. It shows you know both patterns. What They're Really Testing These patterns are rarely asked as standalone questions. They come up when you are designing a fact table and the interviewer watches what you do with the leftover attributes. Having the vocabulary ready is the difference between fumbling and flowing.