Database Design: Understanding Transitive Dependency
What is the best definition of transitive dependency?
a. A condition in which an attribute is dependent on another attribute that is part of the primary key
b. A condition in which an attribute is independent of another attribute that is part of the primary key
c. A condition in which an attribute is dependent on another attribute that is not part of the primary key
d. A condition in which an attribute is independent of another attribute that is not part of the primary key
Answer:
The best definition of transitive dependency is c. A condition in which an attribute is dependent on another attribute that is not part of the primary key.
Transitive dependencies occur when an attribute in a table is functionally dependent on another attribute that is not the primary key. This means that the attribute is indirectly dependent on another attribute through a third attribute. This can lead to data redundancy and anomalies in database design.
For example, if we have attributes A, B, and C in a table, and attribute A is dependent on attribute B, while attribute B is dependent on attribute C, then attribute A is transitive dependent on attribute C. This creates a chain of dependencies that can cause issues in database management.
Avoiding transitive dependencies is important in database design to maintain data integrity and efficiency. By understanding and identifying these dependencies, database developers can create more effective and optimized database systems.