Denormalization – storing multiple copies is OK

Another modeling practice that would be considered a strong anti-pattern in the RDBMS world is denormalization, a practice where storing multiple copies of data is considered acceptable. By multiple copies here, I mean occasionally duplicating attributes across items if that helps answer specific access patterns well! In the RDBMS realm, normalization, often up to the third normal form (3NF), is a standard practice aimed at minimizing data duplication, preventing anomalies, ensuring data integrity, and simplifying data management. A RDBMS data model is deemed to be in the 3NF when all rows are functionally dependent solely on the primary keys. This requires combining or joining data elements at runtime to fulfill data access requirements, making traditional RDBMS heavily reliant on JOIN operations.

In the e-commerce scenario discussed earlier, a critical access pattern involves retrieving all products associated with a specific...