- • 1970 E.F.Codd introduces 1st Normal Form (1NF)
- • 1971 E.F.Codd introduces 2nd and 3rd Normal Form (2NF, 3NF)
- • 1974 Codd & Boyce define Boyce/Codd Normal Form (BCNF)
- • 2002 Date, Darween, Lorentzos define 6th Normal Form (6NF)
Goals:
- • Avoid anomalies when inserting, updating or deleting
- • Minimize redesign when extending the schema
- • Make the model informative to users
- • Avoid bias towards a particular style of query
