# First normal form any multivalued attributes have

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First Normal Form: Any multivalued attributes have been removed, so there is a single value at the intersection of each row and column of the table 2. Second Normal Form: Any partial functional dependencies have been removed (nonkey attributes are identified by the whole primary number) 3. Third Normal Form: Any transitive dependencies have been removed (nonkey attributes are identified by only the primary key) Functional Dependencies: a constraint between two attributes in which the value of one attribute is determined by the value of another attribute A  B Determinant: attribute on the left side of the function dependency Candidate Key: an attribute, or combo of attributes, that uniquely identifies a row in a relation o Determines that uniquely identifies the remaining (nonkey) attributes Steps in Normalization Forms Step 0: Represent the View in Tabular Form Step 1: Convert to 1NF - There are no repeating groups in the relation - PK has been defined, which identifies each row in the relation - Problem: contains redundancies and attributes are recorded in three rows. Step 2: Convert to 2NF: - 1NF in which every nonkey attribute is fully functionally dependent on the primary key - Partial functional dependency: nonkey attribute is functionally dependent on part (but not all) of the primary key
- Create a new relation for each primary key attribute that is a determinant in a partial dependency - Move nonkey attributes that are only dependent on this primary key attribute from the old relation to the new relation Step 3: Convert to 3NF: - 2NF and has no transitive dependency - Transitive dependency: a functional dependency between the PK and one or more nonkey attributes that are dependent on the primary key via another nonkey attribute