DBI202 Study Guide Questions with 100%
Correct Answers
c
Suppose relations RA,B) and S(B,C,D) are as follows:
R= A B
12
34
56
S= B C D
451
672
893
Compute the full outer join on B, where R is the left operand and S is the right operand. Find
the correct statement in the list below.
A. The full outer has 6 tuples.
B. The full outer has 3 tuples.
C. The full outer has 4 tuples.
D. The full outer has 5 tuples.
a
QN=1 (6803) A ____ is a logically coherent collection of data with some inherent meaning,
representing some aspect of real world and being designed, built and populated with data for
a specific purpose
a. Database
,b. Database Instance
c. Schema
d. Schema Instance
b
QN=2 (6801) Choose the most correct statement.
a. Database is created and maintained by a DMBS
b. All of the others
c. Database is a collection of data that is managed by a DBMS
d. Database is a collection of information that exists over a long period of time
b
QN=3 (6802) Which of following is never used as a data model?
a. Hierarchical data model
b. None of the others
c. Graph-based data model
d. Tree-based data model
e. Relational data model
a
QN=4 (6817) A ____ is a relation name, together with the attributes of that relation.
a. schema
b. database
c. database instance
d. schema instance
a
,QN=5 (6824) A ___ is a notation for describing the structure of the data in a database, along
with the constraints on that data
a. data model
b. database management system
c. data operation
d. data manipulation
a
QN=6 (6827) A _____ is a language for defining data structures
a. DDL
b. DML
c. DCL
d. None of the others
a
QN=7 (6834) Which statement is used to remove a relation named R?
a. DROP TABLE R;
b. REMOVE TABLE R;
c. DELETE TABLE R;
d. TRUNCATE TABLE R;
b
QN=8 (6829) What is another term for a row in a relational table?
a. Attribute
b. Tuple
c. Field
d. Relation
, d
QN=9 (7961) Given a relation R(A,B,C,D). Which of the followings is trivial?
a. A->AB
b. A->->AB
c. A->BCD
d. A->->BCD
b
QN=10 (7972) Let R(ABCD) be a relation with functional dependencies
{A -> B,
C -> B,
B -> D}
What is the key for R (choose one)
a. AB
b. AC
c. AD
d. BD
a
QN=11 (7966) Suppose R is a relation with attributes A1, A2, A3, A4.
The only key of R is {A1, A2}. So, how many super-keys do R have?
a. 4
b. 8
c. 12
d. 16
a
Correct Answers
c
Suppose relations RA,B) and S(B,C,D) are as follows:
R= A B
12
34
56
S= B C D
451
672
893
Compute the full outer join on B, where R is the left operand and S is the right operand. Find
the correct statement in the list below.
A. The full outer has 6 tuples.
B. The full outer has 3 tuples.
C. The full outer has 4 tuples.
D. The full outer has 5 tuples.
a
QN=1 (6803) A ____ is a logically coherent collection of data with some inherent meaning,
representing some aspect of real world and being designed, built and populated with data for
a specific purpose
a. Database
,b. Database Instance
c. Schema
d. Schema Instance
b
QN=2 (6801) Choose the most correct statement.
a. Database is created and maintained by a DMBS
b. All of the others
c. Database is a collection of data that is managed by a DBMS
d. Database is a collection of information that exists over a long period of time
b
QN=3 (6802) Which of following is never used as a data model?
a. Hierarchical data model
b. None of the others
c. Graph-based data model
d. Tree-based data model
e. Relational data model
a
QN=4 (6817) A ____ is a relation name, together with the attributes of that relation.
a. schema
b. database
c. database instance
d. schema instance
a
,QN=5 (6824) A ___ is a notation for describing the structure of the data in a database, along
with the constraints on that data
a. data model
b. database management system
c. data operation
d. data manipulation
a
QN=6 (6827) A _____ is a language for defining data structures
a. DDL
b. DML
c. DCL
d. None of the others
a
QN=7 (6834) Which statement is used to remove a relation named R?
a. DROP TABLE R;
b. REMOVE TABLE R;
c. DELETE TABLE R;
d. TRUNCATE TABLE R;
b
QN=8 (6829) What is another term for a row in a relational table?
a. Attribute
b. Tuple
c. Field
d. Relation
, d
QN=9 (7961) Given a relation R(A,B,C,D). Which of the followings is trivial?
a. A->AB
b. A->->AB
c. A->BCD
d. A->->BCD
b
QN=10 (7972) Let R(ABCD) be a relation with functional dependencies
{A -> B,
C -> B,
B -> D}
What is the key for R (choose one)
a. AB
b. AC
c. AD
d. BD
a
QN=11 (7966) Suppose R is a relation with attributes A1, A2, A3, A4.
The only key of R is {A1, A2}. So, how many super-keys do R have?
a. 4
b. 8
c. 12
d. 16
a
