Set of keywords about functional dependencies used in Normalization process / Set of functional dependencies that you need to know in Normalization process / Full functional dependency / Partial functional dependency/ Transitive Dependency / Multivalued dependency / Functional dependencies in Normalization process / Define Full, partial, transitive, and multivalued function dependencies
Various Types of Functional Dependencies used in Normalization Process
Full Functional Dependency – Click here to read more…
Definition 1:
If X is a set of attributes and Y
is another set of attributes, then any functional dependency such that X → Y
is said to be a full functional dependency if and only if all the attributes
of Y is functionally dependent on complete X.
In other words, X → Y becomes
invalid if we remove any attribute from X.
Definition 2:
A functional dependency X → Y is a
full functional dependency if removal of any attribute from A results in the
dependency no longer existing

Functional Dependency – Click to read more…
Functional dependency is a
constraint (condition) that describes the relationship between two sets of
attributes. It is written as X → Y. it can be read as, the values of X
determine the values of Y uniquely, or the values of Y are uniquely
determined by the values of X, or Y is functionally dependent on X. Here, X
is determinant,
and Y is dependent.

Multivalued
Dependency– Click to read more…

Partial
Dependency – Click to read more…
It is a type of functional dependency where a
nonkey (nonprime) attribute is functionally dependent on a subset of the
primary key (or candidate key) attribute.
For example, we would say that a functional
dependency XY → A as a partial functional dependency, if there exists other
FDs like X → A or Y → A.
In other words, removal of Y from X → A or removal
of X from Y → A still holds the dependency.

Transitive
Dependency – Click to read more…
Dependency of a nonkey attribute (or set of nonkey
attributes) on another nonkey attribute (or set of nonkey attributes) is
called transitive dependency. For example, if X → Y and Y → Z holds in a relation R(X, Y, Z), then
these FDs imply X → Z (through transitivity axiom). Then X → Z is called
transitive dependency.

Trivial
Functional Dependency – Click to
read more…
The dependency of an attribute (or set of
attributes) on a set of attributes is called trivial functional dependency if
the set of attributes on the Left Hand Side (LHS) of the functional
dependency contains RHS attributes.
In other words, a functional dependency A → B is
said to be trivial if B is subset or equal to A. Other examples are X → X, Y →
Y, AB → AB etc.

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