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MCQOPTIONS
This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Which function is used to identify the title with Least scope? |
| A. | min(credits) |
| B. | max(credits) |
| C. | min(title) |
| D. | min(salary) |
| Answer» B. max(credits) | |
| 2. |
Which function is used to ï¬nd the count of distinct departments? |
| A. | dist |
| B. | distinct |
| C. | count |
| D. | count,dist |
| Answer» B. distinct | |
| 3. |
Select distinct Dept_name from instructor ; How many row(s) are displayed ? |
| A. | 4 |
| B. | 3 |
| C. | 5 |
| D. | error |
| Answer» B. 3 | |
| 4. |
In the section relation which of the following is used as a foreign key? |
| A. | course_id |
| B. | course_id,sec_id |
| C. | room_number |
| D. | course_id,sec_id,room_number |
| Answer» B. course_id,sec_id | |
| 5. |
To replace the relation section with some other relation the initial step to be carried out is |
| A. | delete section; |
| B. | drop section; |
| C. | delete from section; |
| D. | replace section new_table ; |
| Answer» C. delete from section; | |
| 6. |
Identify the error in the section relation |
| A. | no error |
| B. | year numeric (4,0) |
| C. | building varchar (15) |
| D. | sec_id varchar (8) |
| Answer» B. year numeric (4,0) | |
| 7. |
Which of the following can be used as a primary key entry of the instructor relation. |
| A. | dept_name |
| B. | name |
| C. | id |
| D. | all of the mentioned |
| Answer» D. all of the mentioned | |
| 8. |
The department relation has the an entry budget whose type has to be replaced by |
| A. | varchar (20) |
| B. | varchar2 (20) |
| C. | numeric (12,2) |
| D. | numeric |
| Answer» D. numeric | |
| 9. |
In the above DDL command the foreign key entries are got by using the keyword |
| A. | references |
| B. | key reference |
| C. | relating |
| D. | none of the mentioned |
| Answer» B. key reference | |
| 10. |
Which is the main relation which is used in the university database which is referenced by all other relation of the university? |
| A. | teaches |
| B. | course |
| C. | department |
| D. | section |
| Answer» D. section | |
| 11. |
Which of the following is another name for a weak entity? |
| A. | child |
| B. | owner |
| C. | dominant |
| D. | all of the mentioned |
| Answer» B. owner | |
| 12. |
Functional dependencies are a generalization of |
| A. | key dependencies |
| B. | relation dependencies |
| C. | database dependencies |
| D. | none of the mentioned |
| Answer» B. relation dependencies | |
| 13. |
The completeness constraint may be one of the following: Total generalization or specialization, Partial generalization or specialization. Which is the default? |
| A. | total |
| B. | partial |
| C. | should be speciï¬ed |
| D. | cannot be determined |
| Answer» C. should be speciï¬ed | |
| 14. |
If an entity set is a lower-level entity set in more than one ISA relationship, then the entity set has |
| A. | hierarchy |
| B. | multilevel inheritance |
| C. | single inheritance |
| D. | multiple inheritance |
| Answer» E. | |
| 15. |
Consider the employee work-team example, and assume that certain employees participate in more than one work team. A given employee may therefore appear in more than one of the team entity sets that are lower level entity sets of employee. Thus, the generalization is |
| A. | overlapping |
| B. | disjointness |
| C. | uniqueness |
| D. | relational |
| Answer» B. disjointness | |
| 16. |
A Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â constraint requires that an entity belong to no more than one lower- level entity set. |
| A. | disjointness |
| B. | uniqueness |
| C. | special |
| D. | relational |
| Answer» B. uniqueness | |
| 17. |
There are similarities between the instructor entity set and the secretary entity set in the sense that they have several attributes that are conceptually the same across the two entity sets: namely, the identiï¬er, name, and salary attributes. This process is called |
| A. | commonality |
| B. | specialization |
| C. | generalization |
| D. | similarity |
| Answer» D. similarity | |
| 18. |
The reï¬nement from an initial entity set into successive levels of entity subgroupings represents a                  design process in which distinctions are made explicit. |
| A. | hierarchy |
| B. | bottom-up |
| C. | top-down |
| D. | radical |
| Answer» D. radical | |
| 19. |
Which relationship is used to represent a specialization entity? |
| A. | isa |
| B. | ais |
| C. | onis |
| D. | whois |
| Answer» B. ais | |
| 20. |
The entity set person is classiï¬ed as student and employee. This process is called |
| A. | generalization |
| B. | specialization |
| C. | inheritance |
| D. | constraint generalization |
| Answer» C. inheritance | |
| 21. |
A primary key is combined with a foreign key creates |
| A. | parent-child relation ship between the tables that connect them |
| B. | many to many relationship between the tables that connect them |
| C. | network model between the tables that connect them |
| D. | none of the mentioned |
| Answer» B. many to many relationship between the tables that connect them | |
| 22. |
A window into a portion of a database is |
| A. | schema |
| B. | view |
| C. | query |
| D. | data dictionary |
| Answer» C. query | |
| 23. |
Which of the following is a low level operator? |
| A. | insert |
| B. | update |
| C. | delete |
| D. | directory |
| Answer» E. | |
| 24. |
What is a relationship called when it is maintained between two entities? |
| A. | unary |
| B. | binary |
| C. | ternary |
| D. | quaternary |
| Answer» C. ternary | |
| 25. |
In E-R diagram generalization is represented by |
| A. | ellipse |
| B. | dashed ellipse |
| C. | rectangle |
| D. | triangle |
| Answer» E. | |
| 26. |
Key to represent relationship between tables is called |
| A. | primary key |
| B. | secondary key |
| C. | foreign key |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 27. |
Which of the following indicates the maximum number of entities that can be involved in a relationship? |
| A. | minimum cardinality |
| B. | maximum cardinality |
| C. | erd |
| D. | greater entity count |
| Answer» C. erd | |
| 28. |
Given the basic ER and relational models, which of the following is INCORRECT? |
| A. | an attribute of an entity can have more than one value |
| B. | an attribute of an entity can be composite |
| C. | in a row of a relational table, an attribute can have more than one value |
| D. | in a row of a relational table, an attribute can have exactly one value or a null value |
| Answer» D. in a row of a relational table, an attribute can have exactly one value or a null value | |
| 29. |
The total participation by entities is represented in E-R diagram as |
| A. | dashed line |
| B. | double line |
| C. | double rectangle |
| D. | circle |
| Answer» C. double rectangle | |
| 30. |
Let us consider phone_number ,which can take single or several values . Treating phone_numberas an                    permits instructors to have several phone numbers (including zero) associated with them. |
| A. | entity |
| B. | attribute |
| C. | relation |
| D. | value |
| Answer» B. attribute | |
| 31. |
The relation changes can be got back using                  command |
| A. | flashback |
| B. | purge |
| C. | delete |
| D. | getback |
| Answer» B. purge | |
| 32. |
In the above teaches relation †Select * from teaches where Year = ‘2010’†displays how many rows? |
| A. | 2 |
| B. | 4 |
| C. | 5 |
| D. | 1 |
| Answer» B. 4 | |
| 33. |
How can the values in the relation teaches be deleted? |
| A. | drop table teaches; |
| B. | delete from teaches; |
| C. | purge table teaches; |
| D. | delete from teaches where id =’null’; |
| Answer» C. purge table teaches; | |
| 34. |
The relation with primary key can be created using |
| A. | create table instructor (id, name) |
| B. | create table instructor (id, name, primary key(name)) |
| C. | create table instructor (id, name, primary key (id)) |
| D. | create table instructor ( id unique, name ) |
| Answer» D. create table instructor ( id unique, name ) | |
| 35. |
Which one of the following can be treated as a primary key in teaches relation? |
| A. | id |
| B. | semester |
| C. | sec_id |
| D. | year |
| Answer» B. semester | |
| 36. |
What term is used to refer to a speciï¬c record in your music database; for instance; information stored about a speciï¬c album? |
| A. | relation |
| B. | instance |
| C. | table |
| D. | column |
| Answer» C. table | |
| 37. |
The primary key in the section relation is |
| A. | course_id |
| B. | sec_id |
| C. | both course_id and sec_id |
| D. | all the attributes |
| Answer» D. all the attributes | |
| 38. |
If you were collecting and storing information about your music collection, an album would be considered a(n) |
| A. | relation |
| B. | entity |
| C. | instance |
| D. | attribute |
| Answer» C. instance | |
| 39. |
Weak entity set is represented as |
| A. | underline |
| B. | double line |
| C. | double diamond |
| D. | double rectangle |
| Answer» D. double rectangle | |
| 40. |
For a weak entity set to be meaningful, it must be associated with another entity set, called the |
| A. | identifying set |
| B. | owner set |
| C. | neighbour set |
| D. | strong entity set |
| Answer» B. owner set | |
| 41. |
An entity set that does not have sufficient attributes to form a primary key is termed a |
| A. | strong entity set |
| B. | variant set |
| C. | weak entity set |
| D. | variable set |
| Answer» D. variable set | |
| 42. |
The Rectangles divided into two parts represents |
| A. | entity set |
| B. | relationship set |
| C. | attributes of a relationship set |
| D. | primary key |
| Answer» B. relationship set | |
| 43. |
We indicate roles in E-R diagrams by labeling the lines that connect                        to |
| A. | diamond , diamond |
| B. | rectangle, diamond |
| C. | rectangle, rectangle |
| D. | diamond, rectangle |
| Answer» E. | |
| 44. |
The entity relationship set is represented in E-R diagram as |
| A. | double diamonds |
| B. | undivided rectangles |
| C. | dashed lines |
| D. | diamond |
| Answer» E. | |
| 45. |
                         is preferred method for enforcing data integrity |
| A. | constraints |
| B. | stored procedure |
| C. | triggers |
| D. | cursors |
| Answer» B. stored procedure | |
| 46. |
Drop Table cannot be used to drop a table referenced by a                    constraint. |
| A. | local key |
| B. | primary key |
| C. | composite key |
| D. | foreign key |
| Answer» E. | |
| 47. |
Which one of the following uniquely identiï¬es the elements in the relation? |
| A. | secondary key |
| B. | primary key |
| C. | foreign key |
| D. | composite key |
| Answer» C. foreign key | |
| 48. |
Which of the following can be addressed by enforcing a referential integrity constraint? |
| A. | all phone numbers must include the area code |
| B. | certain ï¬elds are required (such as the email address, or phone number) before the record is accepted |
| C. | information on the customer must be known before anything can be sold to that customer |
| D. | then entering an order quantity, the user must input a number and not some text (i.e., 12 rather than ‘a dozen’) |
| Answer» D. then entering an order quantity, the user must input a number and not some text (i.e., 12 rather than ‘a dozen’) | |
| 49. |
             is a special type of integrity constraint that relates two relations & maintains consistency across the relations. |
| A. | entity integrity constraints |
| B. | referential integrity constraints |
| C. | domain integrity constraints |
| D. | domain constraints |
| Answer» C. domain integrity constraints | |
| 50. |
Establishing limits on allowable property values, and specifying a set of acceptable, predeï¬ned options that can be assigned to a property are examples of: |
| A. | attributes |
| B. | data integrity constraints |
| C. | method constraints |
| D. | referential integrity constraints |
| Answer» C. method constraints | |