Types of Dimensions

Concepts covered: dmDimensionTables

Dimensions are the descriptive lookup tables that give meaning to fact rows. A fact row says 'customer_sk = 42, amount = $100.' The dimension tells you customer 42 is 'Alice Zhang from Seattle in the Enterprise segment.' Without dimensions, facts are just numbers. Conformed Dimensions A conformed dimension is shared across multiple fact tables. dim_customer is referenced by fact_sales, fact_returns, fact_support_tickets. The same customer_sk and the same attribute definitions. This is what makes cross-domain analysis possible: 'show me customers who bought product X but also filed a support ticket.' Without conformed dimensions, each fact table defines 'customer' differently. Sales has one customer table, support has another. Their definitions of 'active customer' differ. Cross-domain quer

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