Let a prime attribute be one that appears in at least one candidate key. Let α and β be sets of attributes such that α → β holds but β → α do not hold. Let A be an attribute that is not in α, is not in β, and for which β → A holds. We say that A is transitively dependent on α. We can restate our definition of 3NF as follows: A relation schema R is in 3NF with respect to a set F of functional dependencies if there are no non prime attributes A in R for which A is transitively dependent on a key for R. Show that this new definition is equivalent to the original one.
Answer to relevant QuestionsA functional dependency α → β is called a partial dependency if there is a proper subset γ of α such that γ → β.We says that β is partially dependent on α. A relation ...For each of the following application areas, explain why a relational database system would be inadequate. List all specific system components that would need to be modified.a. Computer-aided designb. Multimedia databasesUsing ODMG C++a. Give schema definitions corresponding to the relational schema shown in Figure, using references to express foreign-key relationships.b. Write programs to compute each of the queries in Exercise 3.10.Consider the schemas for the table people, and the table’s students and teachers, which were created under people, in Section 9.3.Give a relational schema in third normal form that represents the same information. Recall ...Suppose that you have been hired as a consultant to choose a database system for your client’s application. For each of the following applications, state what type of database system (relational, ...
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