First Normal
Form (1NF) – Eliminate Repeating Groups: A
relation R is said to be in First Normal Form (1NF) if and only if all the
attributes of the relation R are atomic
in nature. A table (relation) is in 1NF if
Second Normal Form (2NF) – Eliminate Redundant Data: A relation R is said to be in Second Normal Form (2NF) if and only if
Third Normal Form (3NF) – Eliminate Columns Not Dependant On Key: A relation R is said to be in Third Normal Form (3NF) if and only if
BoyceCodd Normal Form (BCNF): A table is in BCNF if it is in 3NF and if every determinant is a candidate key. A 3NF relation is almost always in BCNF. However, the following conditions define some situations when a 3NF relation may not be in BCNF:
Fourth Normal Form (4NF) – Isolate Independent Multiple Relationships: A table is in 4NF if it is in BCNF and if it has no multivalued dependencies.
Note: No table may contain two or more 1:n or n:m relationships that are not directly related.
Fifth Normal Form (5NF) – Isolate Semantically Related Multiple Relationships: A table is in 5NF, also called "ProjectionJoin Normal Form" (PJNF), if it is in 4NF and if every join dependency in the table is a consequence of the candidate keys of the table.
Note: There may be practical constrains on information that justify separating logically related manytomany relationships.
DomainKey Normal Form (DKNF): A table is in DKNF if every constraint on the table is a logical consequence of the definition of keys and domains. It is a model which is free from all modification anomalies.
Summary of the normalization steps:
 There are no duplicate rows in the table
 Each cell is singlevalued (i.e., there are no repeating groups or arrays)
 Entries in a column (attribute, field) are of the same kind
Second Normal Form (2NF) – Eliminate Redundant Data: A relation R is said to be in Second Normal Form (2NF) if and only if
 It is in the First Normal Form (1NF), and
 No partial dependency exists between nonkey attributes and key attributes
Third Normal Form (3NF) – Eliminate Columns Not Dependant On Key: A relation R is said to be in Third Normal Form (3NF) if and only if
 It is in Second Normal Form (2NF)
 No transitive dependency exists between nonkey attributes and key attributes
BoyceCodd Normal Form (BCNF): A table is in BCNF if it is in 3NF and if every determinant is a candidate key. A 3NF relation is almost always in BCNF. However, the following conditions define some situations when a 3NF relation may not be in BCNF:
 The candidate keys are composite
 There are more than one candidate keys in the relation
 There are some common attributes in the relation
Fourth Normal Form (4NF) – Isolate Independent Multiple Relationships: A table is in 4NF if it is in BCNF and if it has no multivalued dependencies.
Note: No table may contain two or more 1:n or n:m relationships that are not directly related.
Fifth Normal Form (5NF) – Isolate Semantically Related Multiple Relationships: A table is in 5NF, also called "ProjectionJoin Normal Form" (PJNF), if it is in 4NF and if every join dependency in the table is a consequence of the candidate keys of the table.
Note: There may be practical constrains on information that justify separating logically related manytomany relationships.
DomainKey Normal Form (DKNF): A table is in DKNF if every constraint on the table is a logical consequence of the definition of keys and domains. It is a model which is free from all modification anomalies.
Summary of the normalization steps:
Input Relation

Transformation

Output Relation

All Relations

Eliminate variable length record. Remove multiattribute lines in table. 
1NF

1NF

Remove dependency of nonkey attributes on part of a multiattribute key. 
2NF

2NF

Remove dependency of nonkey attributes on other nonkey attributes. 
3NF

3NF

Remove dependency of an attribute of a multi attribute key on an attribute of another (overlapping) multiattribute key. 
BCNF

BCNF

Remove more than one independent multivalued dependency from relation by splitting relation. 
4NF

4NF

Add one relation relating attributes with multivalued dependency. 
5NF

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