Core Concept Mastery • DBMS Module
This is the 'Humpty Dumpty' problem.
Sometimes, you smash a table into pieces (Decomposition) to fix anomalies. But when you try to glue them back together (Join), you get phantom rows—data that wasn't there before!
5NF ensures that when you break a table, you can reconstruct it exactly without losing information or creating fake information. It usually involves complex 3-way relationships (like Agent, Product, Company) that cannot be split into just pairs.
It handles very complex 3-way relationships that can't be simplified into pairs without losing critical connection info.
A Dealer sells a Product for a specific Company. You cannot just say "Dealer sells Product" and "Dealer works for Company" without losing the specific 3-way deal.
"5NF is concerned with?"
Join Dependency (JD).