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Is there any condition we store degenerate dimension in separate table?

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Question added by Mohsin Zubair , Team Lead Of Data warehouse Team , Zong Telecom
Date Posted: 2016/03/16
bilal mustafa
by bilal mustafa , BigData Consultant , LigaData

When the cardinality of column value is high, instead of maintaining a separate dimension and having the overhead of making a join with fact table, degenerated dimensions can be build, Example:  a purchase order number.  These columns store something that we want to have (the purchase order number), but to create an empty dimension table would only slow things down.  So, to ensure we don't feel bad about breaking the "only a measure or a dimension in the fact table" rule, we just CALL them dimensions- even without the table

Mthulisi Moyo
by Mthulisi Moyo , Data Mining Specialist , Econet Wireless Zimbabwe

A degenerate dimension is not normally stored in its own separate table since most of the interesting attributes about it would be stored in another table for analytics

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