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Mon Mar 28 12:56:20 EDT 2016

Normalization

1NF:

- Eliminate repeating groups in individual tables.
- Create a separate table for each set of related data.
- Identify each set of related data with a primary key

2NF:

- 1NF + every non-prime attribute of the table is dependent on the
  whole of every candidate key.

3NF:

- 2NF + all the attributes in a table are determined only by the
  candidate keys of that table and not by any non-prime attributes.

BCNF: (similar to 3NF)

- redundancy based on functional dependency has been removed, although
  other types of redundancy may still exist.

4NF:

- BCNF + eliminate multivalued dependency

5NF:

- every non-trivial join dependency in it is implied by the candidate
  keys.

6NF:

- no nontrivial join dependencies at all, or alternatively:
- 6NF + every JD [Join Dependency] of R is trivial

DKNF:

- database contains no constraints other than domain constraints and
  key constraints.



https://en.wikipedia.org/wiki/Database_normalization
https://en.wikipedia.org/wiki/First_normal_form
https://en.wikipedia.org/wiki/Second_normal_form
https://en.wikipedia.org/wiki/Third_normal_form
https://en.wikipedia.org/wiki/Boyce%E2%80%93Codd_normal_form
https://en.wikipedia.org/wiki/Fourth_normal_form
https://en.wikipedia.org/wiki/Fifth_normal_form
https://en.wikipedia.org/wiki/Sixth_normal_form
https://en.wikipedia.org/wiki/Domain-key_normal_form



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