The Data Vault Handbook - Concepts and Applications

LINK EXAMPLE

Now, we will create a Patient-Doctor Link that connects patients to the doctors who treated them. This Link will join the Patient Hub with the Doctor Hub, representing the relationship between a patient and their assigned doctor.

The hash key for the Patient-Doctor Link will be generated using the busi- ness keys from the respective Hubs, specifically the Patient business key and the Doctor business key, as input values. 3.1.3. SATELLITES Satellites are crucial in the Data Vault model as they store the descriptive attributes associated with Hubs and Links, thereby providing context to the business keys and their relationships. While Hubs focus on capturing business keys and Links represent the relationships between them, Satellites enrich this structure by holding the additional details that define and describe these keys. One of the primary functions of Satellites is to manage the historical track- ing of attribute data. Every time an attribute changes, the Satellite logs the change, allowing for a complete history of the data over time. This is essential for tracking how business keys or their relationships evolve, providing a tem- poral dimension to the data.