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- Question
When an entity instance may be a member of multiple subtypes or it does not have to be a member of a subtype, it is which of the following?
Options- A. Disjoint with total specialization
- B. Disjoint with partial specialization
- C. Overlap with total specialization
- D. Overlap with partial specialization
- Correct Answer
- Overlap with total specialization
- 1. To eliminate definition duplication, XML Schemas define:
Options- A. an intersection table.
- B. global elements.
- C. a normalized definition table.
- D. None of the above is correct. Discuss
- 2. Which type of entity is related to two or more associated entities that each contain specialized attributes that apply to some but not all of the instances of the entity?
Options- A. Supertype entity
- B. Subtype entity
- C. Archetype entity
- D. Instance entity Discuss
- 3. Parenthesis is never required in Postfix or Prefix expressions
Options- A. TRUE
- B. FALSE Discuss
- 4. It is necessary to sort a file before searching a particular item
Options- A. True
- B. False
- C. May or may not be true
- D. None of the above Discuss
- 5. 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
- 6. The HAVING clause does which of the following?
Options- A. Acts like a WHERE clause but is used for groups rather than rows.
- B. Acts like a WHERE clause but is used for rows rather than columns.
- C. Acts like a WHERE clause but is used for columns rather than groups.
- D. Acts EXACTLY like a WHERE clause. Discuss
- 7. When three or more AND and OR conditions are combined, it is easier to use the SQL keyword(s):
Options- A. LIKE only.
- B. IN only.
- C. NOT IN only.
- D. Both IN and NOT IN. Discuss
- 8. If a table has been normalized so that all determinants are candidate keys, then that table is in:
Options- A. 1NF
- B. 2NF
- C. 3NF
- D. BCNF Discuss
- 9. When assessing the table structure of an acquired set of tables with data, accessing the validity of possible referential integrity constraints on foreign keys is (part of) the:
Options- A. first step.
- B. second step.
- C. third step.
- D. fourth step. Discuss
- 10. Legacy data is which of the following?
Options- A. Data contained in a newly-installed system
- B. Data rejected during the installation of a new system
- C. Data contained in a file system
- D. Data contained by a system used prior to the installation of a new system Discuss
Database problems
Search Results
Correct Answer: global elements.
Correct Answer: Supertype entity
Correct Answer: TRUE
Explanation:
Parenthesis is not required because the order of the operators in the postfix /prefix expressions determines the actual order of operations in evaluating the expression
Correct Answer: May or may not be true
Explanation:
If less work is involved in searching a element than to sort and then extract, then we don?t go for sort
If frequent use of the file is required for the purpose of retrieving specific element, it is more efficient to sort the file.
Thus it depends on situation
Correct Answer: A functional dependency between two or more nonkey attributes.
Correct Answer: Acts like a WHERE clause but is used for groups rather than rows.
Correct Answer: Both IN and NOT IN.
Correct Answer: BCNF
Correct Answer: third step.
Correct Answer: Data contained by a system used prior to the installation of a new system
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