A common practice is minimizing redundancy from a relationship or set of relationships. Unnecessary redundancy may cause interruptions to installation, removal and review. Therefore, it helps to reduce the frequency of the relationship. Standard forms are used to eliminate or minimize reuse in website tables.
Suppose a relationship contains a compound or plural attribute. In that case, it violates the original common form, or the relationship is in the foremost common form if it does not have any compound or plural attribute. Relationships are in the first state of normalcy when every attribute in that category is a specified attribute.
To be in the second common form, the relationship must be in the first general form, and the relationship must not contain a partial dependency. Relationships are 2NF if they do not have Minor Dependence, i.e., no non-key attribute (attributes that are not part of any candidate key) depend on any subset set of any table key keys.
The relationship is in a third normal state if there is no dynamic dependence on non-core factors, and it is in a second normal state.
The relationship is in 3NF if at least one of the following scenarios is to rule out all the trivial dependence of the X -> Y.
X is the key. Y is a key attribute (each part of Y is part of a specific candidate key).
Relationship R is in BCNF when R is in Standard Three Form, and in all FD, LHS is the primary key. The BCNF relationship iff in all performance dependencies is insignificant X -> Y, X is the key.
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