Thursday, December 11, 2014

Logical Database Design

1. 
The entity integrity rule states that:
A.no primary key attribute may be null.
B.no primary key can be composite.
C.no primary key may be unique.
D.no primary key may be equal to a value in a foreign key.
2. 
When mapping a many-to-many unary relationship into a relation which of the following is true?
A.One relation is created.
B.Two relations are created.
C.Three relations are created.
D.Four relations are created.
3. 
If no multivalued attributes exist and no partial dependencies exist in a relation, then the relation is in what normal form?
A.First normal form
B.Second normal form
C.Third normal form
D.Fourth normal form
4. 
A foreign key is which of the following?
A.Any attribute
B.The same thing as a primary key
C.An attribute that serves as the primary key of another relation
D.An attribute that serves no purpose
5. 
A transitive dependency is which of the following?
A.A functional dependency between two or more key attributes.
B.A functional dependency between two or more nonkey attributes.
C.A relation that is in first normal form.
D.A relation that is in second normal form.
6. 
When mapping a multivalued attribute into a relation which of the following is true?
A.One relation is created.
B.Two relations are created.
C.Three relations are created.
D.Four relations are created.
7. 
If no multivalued attributes exist in a relation, then the relation is in what normal form?
A.First normal form
B.Second normal form
C.Third normal form
D.Fourth normal form
8. 
A primary key is which of the following?
A.Any attribute
B.An attribute that uniquely identifies each row
C.An attribute that uniquely identifies each column
D.A derived attribute
9. 
The relational model consists of:
A.data in the form of tables.
B.data redundancy.
C.operations using non-SQL languages.
D.unorganized data.
10. 
When mapping a binary many-to-many relationship into a relation which of the following is true?
A.One relation is created.
B.Two relations are created.
C.Three relations are created.
D.Four relations are created.

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