How would you version an address change in a system that tracks address history?

• A. Create a new address version with updated fields, mark the previous as historic, and maintain an active_version pointer.
• B. Overwrite the existing address record with the new fields.
• C. Keep both versions and delete the old one after a retention period.
• D. Create a copy in a separate table and leave the original record untouched.

Answer: (A)

In a system that tracks address history, the important idea is to preserve every past state while clearly identifying the current one. When an address changes, you don’t erase the old details; you create a new version with the updated fields and mark the previous version as historic. Keeping an active_version pointer lets the system quickly fetch the current address while still maintaining a complete, auditable sequence of changes.

This approach gives a strong audit trail: you can see exactly what the address looked like at any point in time, who made changes, and when they occurred. It also supports scenarios like disputes, regulatory compliance, and data recovery, because nothing essential is lost.

Other options fall short of these goals. Overwriting would erase the prior state, breaking the ability to reconstruct history. Keeping versions but deleting old ones after a retention period sacrifices long-term traceability and can obscure how data evolved. Creating a separate copy in another table leaves two sources of truth and adds unnecessary complexity for queries and integrity. By updating to a new version, marking the old one historic, and pointing to the current version, you get a clean, reliable history with an easily accessible current state.