Friday, 9 December 2016

What is trivial functional dependency in dbms

What is trivial functional dependency in DBMS? / Define trivial functional dependency / What is the trivial property in normalization process?


Trivial Functional Dependency


A FD is said to be as Trivial, if it holds for all relations. In other words, a functional dependency A B is said to be trivial, if B is the subset or equal to that of A. That is, if you know the value of B already, you would uniquely determine the value of B.

If all of the right hand side attributes are either subset or equal to the left hand side attributes in a functional dependency, then that particular functional dependency is said to be trivial.

For example, 
  • A → A is trivial, 
  • AB → B is trivial, 
  • {regno, phone} → phone and so on.



Go to keywords page

No comments:

Post a Comment

SQL exercises for beginners one

SQL Exercises for Beginners / Simple SQL Exercises with Answers / Solved SQL exercises / SQL solved exercises with simple conditions / So...