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- Question
The relational model consists of:
Options- A. data in the form of tables.
- B. data redundancy.
- C. operations using non-SQL languages.
- D. unorganized data.
- Correct Answer
- data in the form of tables.
- 1. The entity integrity rule states that:
Options- 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. Discuss
- 2. When mapping a binary many-to-many relationship into a relation which of the following is true?
Options- A. One relation is created.
- B. Two relations are created.
- C. Three relations are created.
- D. Four relations are created. Discuss
- 3. A relation has which of the following properties?
Options- A. Each row is not unique.
- B. Attributes can have the same name within a given table.
- C. Each relation has a unique name.
- D. The order of the columns is significant. Discuss
- 4. Relations are:
Options- A. two-dimensional tables.
- B. three-dimensional tables.
- C. four-dimensional tables.
- D. five-dimensional tables. Discuss
- 5. A primary key is which of the following?
Options- A. Any attribute
- B. An attribute that uniquely identifies each row
- C. An attribute that uniquely identifies each column
- D. A derived attribute Discuss
- 6. If no multivalued attributes exist and no partial dependencies exist in a relation, then the relation is in what normal form?
Options- A. First normal form
- B. Second normal form
- C. Third normal form
- D. Fourth normal form Discuss
- 7. A transitive dependency is which of the following?
Options- 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. Discuss
- 8. When mapping a regular entity into a relation which of the following is true?
Options- A. One relation is created.
- B. Two relations are created.
- C. Three relations are created.
- D. Four relations are created. Discuss
- 9. When mapping a ternary relationship with an associative entity into a relation which of the following is true?
Options- A. One relation is created.
- B. Two relations are created.
- C. Three relations are created.
- D. Four relations are created. Discuss
- 10. When mapping a supertype/subtype relationship which of the following is true?
Options- A. The supertype primary key is assigned to each subtype.
- B. The subtype primary key is assigned to each supertype.
- C. There is no link between the supertype/subtype entities.
- D. There is no primary key/foreign key relationship between a supertype/subtype. Discuss
Logical Database Design problems
Search Results
Correct Answer: no primary key attribute may be null.
Correct Answer: Three relations are created.
Correct Answer: Each relation has a unique name.
Correct Answer: two-dimensional tables.
Correct Answer: An attribute that uniquely identifies each row
Correct Answer: Second normal form
Correct Answer: A functional dependency between two or more nonkey attributes.
Correct Answer: One relation is created.
Correct Answer: Four relations are created.
Correct Answer: The supertype primary key is assigned to each subtype.
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