MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 8 Mcqs, each offering curated multiple-choice questions to sharpen your Database knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
IDENTIFY_THE_STATEMENT.?$ |
| A. | Insert into employee values (1005,Rach,0); |
| B. | Insert into employee values (1002,Joey,335); |
| C. | Insert into employee values (1007,Ross, ); |
| D. | None of the mentioned |
| Answer» B. Insert into employee values (1002,Joey,335); | |
| 2. |
The_primary_key_must_be$ |
| A. | Unique |
| B. | Not null |
| C. | Both Unique and Not null |
| D. | Either Unique or Not null |
| Answer» E. | |
| 3. |
Using the ______ clause retains only one copy of such identical tuples. |
| A. | Null |
| B. | Unique |
| C. | Not null |
| D. | Distinct |
| Answer» D. Distinct | |
| 4. |
In an employee table to include the attributes whose value always have some value which of the following constraint must be used? |
| A. | Null |
| B. | Not null |
| C. | Unique |
| D. | Distinct |
| Answer» E. | |
| 5. |
Tuples with null value |
| A. | Tuples with no null values |
| B. | Tuples with any salary |
| C. | All of the mentioned |
| Answer» C. All of the mentioned | |
| 6. |
The predicate in a where clause can involve Boolean operations such as and. The result of true and unknown is_______ false and unknown is _____ while unknown and unknown is _____ |
| A. | Unknown, unknown, false |
| B. | True, false, unknown |
| C. | True, unknown, unknown |
| D. | Unknown, false, unknown |
| Answer» E. | |
| 7. |
If the attribute phone number is included in the relation all the values need not be entered into the phone number column. This type of entry is given as |
| A. | 0 |
| B. | – |
| C. | Null |
| D. | Empty space |
| Answer» D. Empty space | |
| 8. |
A _____ indicates an absent value that may exist but be unknown or that may not exist at all. |
| A. | Empty tuple |
| B. | New value |
| C. | Null value |
| D. | Old value |
| Answer» D. Old value | |