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Third Normal Form
Informal Presentation
Informal Definition of 3NF
- A relation R is in third normal form if:
- The difference between BCNF and 3NF:
- “B is a member of some candidate key”
- Previous example schema is in 3NF
- Candidate keys here are: (title, city) and (theater, title)
- Theater is not a superkey but city is a member of a cand. key
- What is the problem with this schema?
Notes: