Slowly Changing Dimension - Type IV

Type IV

The Type 4 method is usually referred to as using "history tables", where one table keeps the current data, and an additional table is used to keep a record of some or all changes.

For the above example the original table name is Supplier and the history table is Supplier_History.

Supplier
Supplier_key Supplier_Code Supplier_Name Supplier_State
123 ABC Acme Supply Co IL
Supplier_History
Supplier_key Supplier_Code Supplier_Name Supplier_State Create_Date
123 ABC Acme Supply Co CA 22-Dec-2004

This method resembles how database audit tables and change data capture techniques function.

Read more about this topic:  Slowly Changing Dimension

Famous quotes containing the word type:

    The real American type can never be a ballet dancer. The legs are too long, the body too supple and the spirit too free for this school of affected grace and toe walking.
    Isadora Duncan (1878–1927)