Trivial Functional Dependency Non-trivial Functional Dependency Both A and B None of the aboveAnswer: C) Both A and BExplanation:There are mainly four types of Functional Dependency in DBMS:Trivial functional d
What are Armstrong's Axioms in Functional Dependency in DBMS?Armstrong axioms are a complete set of inference rules or axioms, introduced and developed by William W. Armstrong in 1974. The inference rules are sound which is used to test logical inferences of functional dependencies. The axiom ...
The dependency of an attribute on a set of attributes is known as trivial functional dependency if the set of attributes includes that attribute. Symbolically: A ->B is trivial functional dependency if B is a subset of A. The following dependencies are also trivial: A->A & B->B For exam...
Starting from SQL-99, the concept of “functional dependency” was introduced; a column B is functionally dependent on columns {A1, A2} in a result set if all rows which share the same value of A1 and the same value of A2 necessarily share the same value of B. Then ...
We describe an algorithm to test whether a multivalued dependency is implied by a set of functional and join dependencies. The worst case running time of the algorithm is O ( nm ), where n is the length of the input and m is the number of the attributes in the universe. We also ...
Therefore, we must know how to calculate closure set of functional dependencies before Normalization. A functional dependency from "A" to "B" is said to be trivial if "B" is a subset of "A".ExampleIn the corresponding relation,Tuple A C t1 a1 c1 t2 a1 c1 t3 a2 c2 t3 a2 c2 t4 a3...