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Everything about Fifth normal form

Database normalization

Fifth normal form (5NF), also known as projection–join normal form (PJ/NF), is a level of database normalization designed to remove redundancy in relational databases recording multi-valued facts by isolating semantically related multiple relationships. A table is said to be in the 5NF if and only if every non-trivial join dependency in that table is implied by the candidate keys. It is the final normal form as far as removing redundancy is concerned. Wikipedia →

🧭 Start here: a 6-step reading path

  1. Read the overview: Fifth normal formA 5-minute orientation
  2. Pick up a classic book: American FilmThe most-reprinted book on the subject
  3. Read the landmark paper: Normal Forms in Relational Databases: Analysis from First to Fifth Normal Form and Boyce-Codd Normal FormCited 0 times
  4. Go sideways: Fourth normal formA closely related topic
  5. Go sideways: Sixth normal formA closely related topic

đź“– Definitions

Noun A stage in the normalization of a relational database in which a database is in fourth normal form and every join dependency is implied by the candidate keys.

🗂️ The subject at a glance

  1. Example

🏆 Landmark papers (most cited)

đź“š Books worth reading

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