Database :: All Aptitude Test ::

1.The result which operation contains all pairs of tuples from the two relations, regardless of whether their attribute values match.
A. Join
B. Cartesian product
C. Intersection
D. Join

2.The result which operation contains all pairs of tuples from the two relations, regardless of whether their attribute values match.
A. Join
B. Cartesian product
C. Intersection
D. Join

3.The _______operation performs a set union of two “similarly structured” tables :
A. Union
B. Join
C. Product
D. Union

4.The most commonly used operation in relational algebra for projecting a set of tuple from a relation is :
A. Join
B. Projection
C. Select
D. Join

5.The _______ operator takes the results of two queries and returns only rows that appear in both result sets.
A. Union
B. Intersect
C. Difference
D. Union

6.A ________ is a pictorial depiction of the schema of a database that shows the relations in the database, their attributes, and primary keys and foreign keys.
A. Schema diagram
B. Relational algebra
C. Database diagram
D. Schema diagram

7.The _________ provides a set of operations that take one or more relations as input and return a relation as an output.
A. Schematic representation
B. Relational algebra
C. Scheme diagram
D. Schematic representation

8.The JOIN operation which uses any of the comparison operators is classified as :
A. THETA JOIN
B. CHI-JOIN
C. PI-JOIN
D. THETA JOIN

9.The kind of operation by which one tuple can be created with the help of combining tuples from two relations is classified as :
A. square operation
B. join operation
C. division operation
D. square operation

10.Consider two tuples X and Y, the operation whose result includes tuples that are only in X but not in Y is classified as :
A. square of relation X and Y
B. union of relation X and Y
C. intersection of relation X and Y
D. square of relation X and Y

11.Consider two tuples X and Y, the operation whose result includes tuples that are only in X but not in Y is classified as :
A. square of relation X and Y
B. union of relation X and Y
C. intersection of relation X and Y
D. square of relation X and Y

12.As compared to Cartesian product, the tuples which appears in the result by applying JOIN are the ones :
A. that fulfills the condition
B. that does not fulfill the condition
C. that are nested
D. that fulfills the condition

13.Consider two tuples R and S, the maximum size of R and S relations is divided to expected size of join is classified as :
A. equi join selectivity
B. natural selectivity
C. join selectivity
D. equi join selectivity

14.In the notation for query trees, the node which is used to terminate the execution is classified as :
A. attribute nodes
B. leaf nodes
C. stem nodes
D. attribute nodes

15.The expression used in relational calculus to specify request of retrieval is classified as :
A. declarative expression
B. procedural expression
C. structural expression
D. declarative expression

16.The compatibility condition which states that the relations for union and intersection operations must consist of same type of tuples is classified as :
A. union compatibility
B. intersect compatibility
C. row compatibility
D. union compatibility

17.The degree of the PROJECT operation is equal to :
A. number of entities
B. number of attributes
C. number of columns
D. number of entities

18. Because of the calculus expression, the relational calculus is considered as :
A. procedural language
B. non procedural language
C. structural language
D. procedural language

19.The expression used in relational calculus to specify request of retrieval is classified as :
A. declarative expression
B. procedural expression
C. structural expression
D. declarative expression

20.The value of the atom which evaluates either condition is TRUE or FALSE for particular combination of tuples is classified as :
A. intersection value
B. union value
C. truth value
D. intersection value

21. The types of quantifiers are :
A. universal quantifier
B. existential quantifier
C. local quantifier
D. universal quantifier

22.The expression which specifies the procedure to retrieve rather than retrieval content is classified as :
A. procedural expression
B. structural expression
C. functional expression
D. procedural expression

23.A second form of relational calculus, is known as :
A. Domain relational calculus
B. Relational calculus
C. Tuple relational calculus
D. Domain relational calculus

24.The restricted tuple relational calculus is equivalent to the :
A. Tuple relational calculus
B. Attribute relational calculus
C. Domain relational calculus
D. Tuple relational calculus

25.In domain relational calculus, all values that appear in tuples of the expression are values from :
A. Views
B. Domain
C. Relation
D. Views

26.Find the names of all instructors in the Physics department together with the course id of all courses they teach:
A. {< c > | Э s (< c, a, s, y, b, r, t >ε section ∧s = “Fall” ∧ y = “2009” ∨Эu (< c, a, s, y, b, r, t >ε section ∧s = “Spring” ∧ y = “2010”
B. {< n, c > | Э i, a (< i, c, a, s, y > ε teaches ∧ Э d, s (< i, n, d, s > ε instructor ∧ d = “Physics”))}
C. {< n > | Э i, d, s (< i, n, d, s > ε instructor ∧ s > 80000)}
D. {< c > | Э s (< c, a, s, y, b, r, t >ε section ∧s = “Fall” ∧ y = “2009” ∨Эu (< c, a, s, y, b, r, t >ε section ∧s = “Spring” ∧ y = “2010”

27.Which of the following is the comparison operator in tuple relational calculus :
A.
B. =
C. ε
D.

28. In domain relaional calculus “there exist” can be expressed as :
A. (P1(x))
B. (P1(x)) Э x
C. V x (P1(x))
D. (P1(x))

29.“Find all students who have taken all courses offered in the Biology department.” The expressions that matches this sentence is :
A. Э t ε r (Q(t))
B. ∀ t ε r (Q(t))
C. ¬ t ε r (Q(t))
D. Э t ε r (Q(t))

30. Find the ID, name, dept name, salary for instructors whose salary is greater than $80,000 :
A. {t | t ε instructor ∧ t[salary] > 80000}
B. Э t ∈ r (Q(t))
C. {t | Э s ε instructor (t[ID] = s[ID]∧ s[salary] > 80000)}
D. {t | t ε instructor ∧ t[salary] > 80000}


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