Junk Dimensions And Degenerate Dimension

Junk Dimensions 





  • Combine low-cardinality attributes that don’t belong in existing dimensions into a junk dimension 
  • Avoids creating many small dimension tables; for the purpose of simplifying the model.

Degenerate Dimension




  • A key without its related dimension
  • Provides grouping and business meaning (i.e: the college-department code in a university; this code is usually well known by the decision-makers or the business owners)

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