← Learn/Part 2 · Multiple tables

Why was the store's schema laid out exactly this way? Normalization is the theory that explains how to avoid duplication and anomalies, step by step (1NF → 2NF → 3NF → BCNF). It's one of the most important engineering skills. There's more reasoning than syntax here: we work through the forms on examples from our schema, spot violations in the data, and normalize by hand.