Datawarehousing mit Oracle

A head table represents a master data entity.

Such a table has a

• Surrogate key
• Business key (usually the primary key in the data source system)
• Static data that (supposedly) doesn't change (really?).
• Possibly further »SCD1« attributes.

In a data vault model, head tables can be compared to hub tables.

Business attributes that might change are stored in version tables.

The version table references the head table (foreign key to the head table's surrogate key?)

A valid_from and a valid_to column declares the time range in which the data in the record was actually valid.

In a data vault model, version tables can be compared to satellite tables.

Generally (allegedly: always), foreign keys point to primary keys in head tables. Thus, it is independent of the (changing) values in version tables.