Q1. Given the basic ER and relational models, which of the following is
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
Q2. Consider the following ER diagram
The minimum number of tables needed to represent M, N, P, R1, R2 is
After Minimizing this ER diagram we will convert it into a relational model.
As we know ‘Places’& ‘Order’ will be combined so what will be the correct
degree of ‘PlacesOrder’ Table.
After Minimizing this ER diagram we will convert it into relational model.
How many attributes will be created in ‘Includes’ Table?
Q5. For a weak entity set to be meaningful, it must be associated with another
entity set in combination with some of their attribute values, is called as:
a) Neighbor Set
b) Strong Entity Set
c) Owner Entity Set
Q6. Which one of the following pairs is correctly matched in the context
of database design?
List — I List — II
I. Specialization A. Result of taking the union of two more
disjoint (lowerlevel) entity setsto produce
a higher-level entity set.
II. Generalization B. Express the number of entities to
which another entitycan be associated via
a relationship set
III. Aggregation C. Result of taking a subset of a higherlevel entity set to form a lower-level
IV. Mapping cardinalities D. An abstraction in which relationship
sets (along with their associated entity
sets) are treated as higher-level
a) I-D, II-A, III-B, IV-C
b) I-D, II-C, III-B, IV-A
c) I-C, II-D, III-A, IV-B
d) I-C, II-A, III-D, IV-B
Q7. An ER model of a database consists of entity types A and B. These are
connected by a relationship R which does not have its own attribute.
Under which one of the following conditions, can the relational table for
R be merged with that of A?
a) Relationship R is one-to-many and the participation of A in R is total.
b) Relationship R is one-to-many and the participation of A in R is partial.
c) Relationship R is many-to-one and the participation of A in R is total.
d) Relationship R is many-to-one and the participation of A in R is partial.
Q8. Given an instance of the STUDENTS relation as shown below:
For (StudentName, StudentAge) to be a key for this instance, the value X
should NOT be equal to ________.
Q9. In E-R model, Y is the dominant entity and X is subordinate entity
a) If X is deleted, then Y is also deleted
b) If Y is deleted, then X is also deleted
c) If Y is deleted, then X is not deleted
d) None of the above
Q10. Which one of the following is used to represent the supporting manyone relationships of a weak entity set in an entity-relationship diagram?
a) Diamonds with double/bold border
b) Rectangles with double/bold border
c) Ovals with double/bold border
d) Ovals that contain underlined identifiers
Q11. In an Entity-Relationship (ER) model, suppose R is a many-to-one
relationship from entity set E1 to entity set E2. Assume that E1 and E2
participate totally in R and that the cardinality of E1 is greater that the
cardinality of E2.
Which one of the following is true about R?
a) Every entity in E1 is associated with exactly one entity in E2.
b) Some entity in E1 is associated with more than one entity in E2.
c) Every entity in E2 is associated with exactly one entity in E1.
d) Every entity in E2 is associated with at most one entity in E1.
Q12. Consider the two statements given below:
S1: Each record of referencing relation can relate to at most one record
of referenced relation.
S2: Each record of referenced relation can relate to many (0 or more)
records of referencing relation.
a) S1 is true, S2 is false
b) S1 is false, S2 is false
c) S1 is true, S2 is true
d) S1 is false, S2 is true
Q13. Consider the two statements given below:
S1: Existence of multiple foreign keys in a same relation is not possible.
S2: There cannot exist multiple foreign keys in the same relation
because there cannot exist multiple attributes in the relation that
refer to primary keys in two or more other relations.
a) S1 is true, S2 is false
b) Both are true and S2 is the correct reason for S1
c) Both are true but S2 is not the correct reason for S1
d) Both are false
Q14. An Entity-Relation (ER) model represents
a) The various entity types of interest and the relationships among them in
the domain being modeled.
b) Various tables and links among them in the domain modeled.
c) The various entity types of interest and the relationship among them in the
domain being modeled along with operations to be performed on data.
d) Various tables and links among them in the domain modeled along with
operations to be performed on data.
Q15. Which of the following statement is true
a) Three-schema architecture is part of the Entity-Relationship Data model.
b) Concept of Entity is used in RDBMS
c) Weak entity contains partial key
d) Strong entity can exist without primary key