Dimension Tables

A dimension table is a table in a star schema of a data warehouse. A dimension table stores attributes, or dimensions, that describe the objects in a fact table.

Dimension table definitions load dimension records into the data mart. These dimension patterns can be applied to a dimension table:

• Dimension key

  Dimension keys are unique identifiers used as foreign keys on the fact tables. These keys allow optimized joins between the fact records and dimension records.

• Trace columns

  Trace columns keep audit information on each record.

• Slowly changing

  Slowly changing dimensions allow historical preservation of important dimension attributes.