Database Normalization: Split Repeated Facts Carefully
A customer address copied into every order row can create inconsistent updates. This guide gives you a small, testable way to approach the issue before changing a live system.
A practical workflow
- Identify facts with different lifetimes and use related tables with explicit foreign keys.
- Keep the historical shipping address on an order when that snapshot is a business requirement.
What to check
Normalization is a design tool, not a contest for the most tables; test common reads and update rules. Compare the result with the original problem and record what changed. If a measurement or test does not support the change, revisit the assumption rather than adding more complexity.
Keep the experiment small enough to reverse. Document the starting state, the change and the result so another person can repeat the process. Product menus and versions can change, so check the current documentation for your environment.
Official reference: Read the documentation.