Database Management System MCQ Quiz Set 7

DBMS MCQ QUIZ
Quiz1234567

Question 1. A_____ is a query that retrieves rows from more than one table or view.

(A) Join

(B) End

(C) Start

(D) All of the mentioned

View Answer
(A) Join

Question 2. Which oracle is the join condition is specified using the WHERE clause?

(A) Oracle 9i

(B) Oracle 8i

(C) Pre-oracle 8i

(D) Pre-oracle 9i

View Answer
(D) Pre-oracle 9i

Question 3. How many join types in the join condition?

(A) 2

(B) 3

(C) 5

(D) 4

View Answer
(C) 5

Question 4. Which product is returned in a join query have no join condition: 

(A) Equijoins

(B) Cartesian

(C) Both Equijoins and Cartesian

(D) None of the mentioned

View Answer
(B)Cartesian

Question 5. Which is a join condition contains an equality operator 

(A) Cartesian

(B) Both Equijoins and Cartesian

(C) Equijoins

(D) None of the mentioned

View Answer
(C) Equijoins

Question 6. Which join refers to join records from the writing table that have no matching key in the left table that are included in the result set? 

(A)Left outer join

(B)Half outer join

(C)Full outer join

(D) Right outer join

View Answer

(D) Right outer join

Question 7. Which operations are allowed in a join view: 

(A)UPDATE

(B)INSERT

(C)DELETE

(D)All of the mentioned

View Answer
(D)All of the mentioned

Question 8. The intersection operator is used to get the _____ tuples. 

(A) Different

(B) Common

(C) All

(D) Repeating

View Answer
(B) Common

Question 9. The union operation automatically __________ unlike the select clause.

(A) Adds tuples

(B) Eliminates unique tuples

(C) Eliminates duplicate

(D) Adds common tuples

View Answer
(C) Eliminates duplicate

Question 10. The number of attributes in relation is called as its _________?

(A) Cardinality

(B) Tuples

(C) Entity

(D) Degree

View Answer
(D) Degree

Question 11. Which of the following is not an integrity constraint?

(A) Positive

(B) Unique

(C) Not null

(D) Check ‘predicate’

View Answer
(A) Positive

Question 12. CREATE TABLE Employee(Emp_id NUMERIC NOT NULL, Name VARCHAR(20), dept_name VARCHAR(20), Salary NUMERIC UNIQUE(Emp_id,Name));
INSERT INTO Employee VALUES(1002, Ross, CSE, 10000)
INSERT INTO Employee VALUES(1006,Ted,Finance, );
INSERT INTO Employee VALUES(1002,Rita,Sales,20000); 

What will be the result of the query?

(A) All statements executed

(B) Error in creating a statement

(C) Error in insert into Employee values(1008,Ross,Sales,20000);

(D) Error in insert into Employee values(1006,Ted,Finance, );

View Answer
(C) Error in insert into Employee values(1008,Ross,Sales,20000);

Question 13. The foreign key is the one in which the ________ of one relation is referenced in another relation. 

(A) Foreign key

(B) References

(C) Check constraint

(D) Primary key

View Answer
(D) Primary key

Question 14. Which of the following is used to delete the entries in the referenced table when the tuple is deleted in course table? 

(A) Set null

(B) Delete

(C) Delete cascade

(D) All of the mentioned

View Answer
(C) Delete cascade

Question 15. Data integrity constraints are used to:

(A) Control who is allowed access to the data

(B) Ensure that duplicate records are not entered into the table

(C) Prevent users from changing the values stored in the table

(D) Improve the quality of data entered for a specific property (i.e.,table column)

View Answer
(D) Improve the quality of data entered for a specific property (i.e.,table column)

Question 16. Consider attributes ID, CITY and NAME. Which one of this can be considered as a super key? 

(A) ID

(B) NAME

(C) CITY

(D) CITY, ID

View Answer
(A) ID

Question 17. The subset of a super key is a candidate key under what condition? 

(A) All subsets are super keys

(B) No proper subset is a super key

(C) Subset is a super key

(D) Each subset is a super key

View Answer
(B) No proper subset is a super key

Question 18. Which one of the following cannot be taken as a primary key? 

(A) Street

(B) Register number

(C) Id

(D) Dept_id

View Answer
(A) Street

Question 19. A many-to-many relationship between two entities usually results in how many tables? 

(A) One

(B) Two

(C) Three

(D) Four

View Answer
(C) Three

Question 20. An ________ is a set of entities of the same type that share the same properties, or attributes. 

(A) Entity set

(B) Relation set

(C) Attribute set

(D) Entity model

View Answer
(A) Entity set

Question 21. Every weak entity set can be converted into a strong entity set by:

(A) using aggregation

(B) using generalization

(C) adding appropriate attributes

(D) none of the above

View Answer
(C) adding appropriate attributes

Question 22. E-R modelling technique is a :

(A) Top-down approach

(B) Top-down approach

(C) Left-right approach

(D) None of the above

View Answer
(A) Top-down approach

Question 23. The attribute AGE is calculated from DATE_OF_BIRTH. The attribute AGE is

(A) Multi-valued

(B) Single valued

(C) Composite

(D) Derived

View Answer
(D) Derived

Question 24. Which of the following can be a multivalued attribute? 

(A) Name

(B) Phone_number

(C) Date_of_birth

(D) All of the mentioned

View Answer
(B) Phone_number

Question 25. Entity is a _________ ?

(A) Object of relation

(B) Present working model

(C) Model of relation

(D) Thing in real world

View Answer
(D) Thing in real world

Quiz1234567