Relational modeling (3NF)

Relational modeling (3NF)

Design operational schemas that store every fact once: normal forms, keys, lookups and constraints.

Outcome: You can normalize a messy table into a clean relational model and explain each step.

1. 1

   Normalize an order system to 3NF

   Remove repeating groups and dependencies until every fact is stored exactly once.

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2. 2

   Lookup tables, keys and constraints

   Replace free-text codes with lookups and decide which key identifies each row.

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3. 3

   Supertypes and subtypes

   Model things that share a core but differ in detail, without a wide table full of NULLs.

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4. 4

   Associative entities and referential integrity

   Resolve a many-to-many into an entity of its own, and let foreign keys keep it honest.

   Build it in the Model Builder · 12 min · instant checks