Dimensional Data Modeling - Level

Star Schema


A level in a dimensional hierarchy is a set of attributes that has:

  • an mandatory identifier attribute (known also as the business identifier)
  • and descriptive attributes (optional)


A level is just metadata information that permits to:

  • rewrite a dimensional query. (ie when a descriptif attribute is chosen, the query can be rewrite to use its identifier in order to fine an aggregate followed by a lookup to retrieve the descriptif attribute)
  • define the grain of the query in order to see if there is an aggregate table that can serve it


In a relational database, the data of a level can be stored

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