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- Question
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.
- Correct Answer
- One relation is created.
- 1. 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
- 2. 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
- 3. 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. Discuss
- 4. 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
- 5. 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
- 6. 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
- 7. 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
- 8. When mapping a multivalued attribute 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. Which of the following is true concerning triggers?
Options- A. You do not create them with SQL.
- B. They execute against only some applications that access a database.
- C. They have an event, condition, and action.
- D. They cannot cascade (cause another trigger to fire). Discuss
- 10. What type of join is needed when you wish to include rows that do not have matching values?
Options- A. Equi-join
- B. Natural join
- C. Outer join
- D. All of the above. Discuss
Logical Database Design problems
Search Results
Correct Answer: A functional dependency between two or more nonkey attributes.
Correct Answer: Second normal form
Correct Answer: data in the form of tables.
Correct Answer: no primary key attribute may be null.
Correct Answer: Three relations are created.
Correct Answer: Four relations are created.
Correct Answer: The supertype primary key is assigned to each subtype.
Correct Answer: Two relations are created.
Correct Answer: They have an event, condition, and action.
Correct Answer: Outer join
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