Ch 05: Database Data Models

Which of the following is NOT a valid component of a Data Flow Diagram (DFD)?

Which of the following graphical diagrams uses specific symbols to indicate the sequential flow of a procedure or system algorithm being explained?

Desirable properties of relational database design include ________.

Which of the following are essential and desirable properties of a good relational database schema design during relation decomposition?

The functional dependency A -> B for a relation schema R(A, B, C, D) implies that ________.

t1[A] = t2[A] => t1[B] = t2[B]

If AB -> CD is a functional dependency for relation schema R(A, B, C, D), which of the following statements will always hold?

{A, B}+ = {A, B, C, D}

Given the functional dependencies {AB -> C, C -> D} for relation schema R(A, B, C, D), the inferred dependency AB -> D is derived using which Armstrong inference rule?

AB -> C, C -> D => AB -> D

Given the set of functional dependencies {AB -> CDE, A -> E} for relation schema R(A, B, C, D, E), which of the following can be inferred?

{A, B}+ = {A, B, C, D, E}

Consider the table (Relation) CARS with schema CARS(REGNO, MODEL, COLOUR, OID), where REGNO is the single-attribute primary key and OID is a foreign key identifying the car's owner. In which highest normal form is this table?

CARS(REGNO, MODEL, COLOUR, OID)

In relational database normalization, which normal form strictly prohibits transitive dependencies on non-prime attributes?

FD: X -> Y and Y -> Z (where Y is non-prime) => Violates 3NF