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- Question
A regular subquery can be processed:
Options- A. from the top down.
- B. from the bottom up.
- C. by nesting.
- D. None of the above is correct.
- Correct Answer
- from the bottom up.
- 1. The NOT EXISTS keyword will be true if:
Options- A. any row in the subquery meets the condition.
- B. all rows in the subquery fail the condition.
- C. both of these two conditions are met.
- D. neither of these two conditions is met. Discuss
- 2. What SQL command can be used to add columns to a table?
Options- A. MODIFY TABLE TableName ADD COLUMN ColumnName
- B. MODIFY TABLE TableName ADD ColumnName
- C. ALTER TABLE TableName ADD COLUMN ColumnName
- D. ALTER TABLE TableName ADD ColumnName Discuss
- 3. In a 1:N relationship, the foreign key is placed in:
Options- A. either table without specifying parent and child tables.
- B. the parent table.
- C. the child table.
- D. either the parent table or the child table. Discuss
- 4. In a 1:1 relationship, the foreign key is placed in:
Options- A. either table without specifying parent and child tables.
- B. the parent table.
- C. the child table.
- D. either the parent table or the child table. Discuss
- 5. A primary key should be defined as:
Options- A. NULL.
- B. NOT NULL.
- C. Either of the above can be used.
- D. None of the above are correct. Discuss
- 6. How can you find rows that do not match some specified condition?
Options- A. EXISTS
- B. Double use of NOT EXISTS
- C. NOT EXISTS
- D. None of the above is correct. Discuss
- 7. What SQL command can be used to delete columns from a table?
Options- A. MODIFY TABLE TableName DROP COLUMN ColumnName
- B. MODIFY TABLE TableName DROP ColumnName
- C. ALTER TABLE TableName DROP COLUMN ColumnName
- D. ALTER TABLE TableName DROP ColumnName Discuss
- 8. Which of the following SQL statements are helpful in database redesign?
Options- A. Correlated subqueries only
- B. EXISTS/NOT EXISTS expressions only
- C. Both of the above are helpful
- D. None of the above are helpful. Discuss
- 9. A tool that can help designers understand the dependencies of database structures is a:
Options- A. dependency graph.
- B. data model.
- C. graphical display.
- D. None of the above is correct. Discuss
- 10. The data model that is produced from reverse engineering is:
Options- A. a conceptual model.
- B. an internal model.
- C. a logical model.
- D. None of the above is correct. Discuss
Database Redesign problems
Search Results
Correct Answer: all rows in the subquery fail the condition.
Correct Answer: ALTER TABLE TableName ADD ColumnName
Correct Answer: the child table.
Correct Answer: either table without specifying parent and child tables.
Correct Answer: NOT NULL.
Correct Answer: Double use of NOT EXISTS
Correct Answer: ALTER TABLE TableName DROP COLUMN ColumnName
Correct Answer: Both of the above are helpful
Correct Answer: dependency graph.
Correct Answer: None of the above is correct.
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