How to manage business key evolution within the business process

Rhys Hanscombe
Sep 5, 2023
2 min read

At the 2023 Data Vault Conference, Jean-François Saluden and Stéphane Vivien from Follow Us tackled a challenge that every data professional faces: how do you manage business keys (BKs) when they change over time? Here’s a friendly summary of their session, plus a reminder to join our forum and stay connected with the community!

Why Are Business Keys So Tricky?

Business keys are essential for linking data across systems and building a consolidated, 360° view of business objects. Ideally, a BK is immutable, non-ambiguous, and meaningful—think social security numbers or natural composite keys. But in the real world, BKs can and do change:

Data quality corrections (e.g., standardizing phone numbers)
Enriching objects with new info (e.g., adding an email address)
Changes in identifying info (e.g., name changes, new addresses)
Composite BKs are especially prone to evolution.

The Data Vault Approach: Helper Tables to the Rescue

Data Vault offers a global vision through BKs, but what happens when those keys change? The answer: Helper Tables!

Helper Tables link operational IDs from each source system to their corresponding BKs and hash keys (HKs).
They track the evolution of BKs for the same business object across time and systems.
One Helper Table per source system, loaded alongside Hubs in the Raw Data Vault.
These tables enable you to build “Same-As Links” for a consolidated view in your datamarts, or provide an operational view when needed.

Real-World Example: The Business School Contact

Imagine a business school tracking a contact through Marketing, CRM, and Campus systems:

The contact starts with just an email in Marketing.
As they move to CRM, more info is added (name, DoB, new email).
In the Campus system, the contact gets a student email and more updates.
Now, three different BKs exist for the same person!

Helper Tables allow you to:

Map all operational IDs and BKs for the same object.
Track changes and consolidate history.
Build a “reference BK” (the first seen) to preserve historical data and ensure consistent reporting.

Key Benefits

360° vision: Get a complete view of objects, even as BKs change.
Conformed and operational dimensions: Build both consolidated and operationally-oriented dimensions.
Preserved history: Reference BKs ensure that facts and dimensions remain stable over time.
Operational data management: Full tracking at the business object level for governance and analytics.

Join the Data Community!

Sign up to our forum: Share your experiences, ask questions, and connect with fellow data enthusiasts.
Stay up to date: We host regular webinars, workshops, and meetups—don’t miss out!
Shape the future: Your feedback and participation help us build better tools and resources for everyone.

Final Thoughts

Business key evolution is a fact of life in data management, but with the right patterns—like Helper Tables in Data Vault—you can keep your data warehouse robust, auditable, and ready for anything. Let’s keep learning and building together

Ready to master business key evolution? Join the conversation, sign up for our next webinar, and let’s build the future of data together!