The fl attened, denormalized dimension tables with repeating textual values makedata modelers from the operational world uncomfortable. Let’s revisit the case studyproduct dimension table. The 300,000 products roll up into 50 distinct departments. Rather than redundantly storing the 20-byte department description in theproduct dimension table, modelers with a normalized upbringing want to store a2-byte department code and then create a new department dimension for the department decodes. In fact, they would feel more comfortable if all the descriptors in theoriginal design were normalized into separate dimension tables. They argue thisdesign saves space because the 300,000-row dimension table only contains codes,not lengthy descriptors.
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