Functional Dependency Closure Explained for Database Design
What Is Meant by the Closure of a Set of Functional Dependencies? A functional dependency is a one-way dependency between two attributes at any given time. For a unique attribute of value A there is one value of the attribute B associated with it through the relation. Even if the values for the attribute change, there …
Read MoreDatabase Anomalies: Insertion, Deletion, and Modification
Insertion, Deletion, and Modification Anomalies Are Considered Bad An insertion anomaly is a situation that arises when one is prevented from inserting data into a relation because the complete primary key is not available. No part of a primary key can be null. Harrington (2009) points out that insertion anomalies …
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