Technical :: All Aptitude Test ::

Hassan
1.Updates that violate are disallowed?
A. Integrity constraints
B. Transaction control
C. Authorization
D. Integrity constraints

2.The union operation is represented by?
A.
B. U
C.
D.

3.The intersection operator is used to get the tuples?
A. Different
B. Common
C. Repeating
D. Different

4.The union operation automatically unlike the select clause?
A. Adds tuples
B. Eliminates unique tuples
C. Adds common tuples
D. Adds tuples

5.If we want to retain all duplicates, we must write in place of union?
A. Union all
B. Union some
C. Intersect all
D. Union all

6.What is output of queries which are given below ?
A. Only tuples from second part
B. Only tuples from the first part which has the tuples from second part
C. Tuples from both the parts
D. Only tuples from second part

7.The number of attributes in relation is called as its?
A. Cardinality
B. Degree
C. Tuples
D. Cardinality

8.Which clause is an additional filter that is applied to the result?
A. Select
B. Group-by
C. Having
D. Select

9.Which joins are SQL server default?
A. Outer
B. Inner
C. Equi
D. Outer

10.The is essentially used to search for patterns in target string?
A. Like Predicate
B. Null Predicate
C. In Predicate
D. Like Predicate

11.Which an indicates an absent value that may exist but be unknown or that may not exist at all?
A. Empty tuple
B. New value
C. Null value
D. Empty tuple

12.If the attribute phone number is included in the relation all the values need not be entered into the phone number column. This type of entry is given as?
A. 0
B. _
C. Null
D. 0

13.What is output of given source code?
A. Tuples with null value
B. Tuples with no null values
C. Tuples with any salary
D. Tuples with null value

14.In an employee table to include the attributes whose value always have some value which of the following constraint must be used?
A. Null
B. Not null
C. Unique
D. Null

15. Using which clause retains only one copy of such identical tuples?
A. Null
B. Unique
C. Not null
D. Null

16.Some of these insert statements will produce an error. Identify the statement.?
A. Insert into employee values (1005,Rach,0);
B. Insert into employee values (1002,Joey,335);
C. Insert into employee values (1007,Ross, );
D. Insert into employee values (1005,Rach,0);

17.The primary key must be?
A. Unique
B. Not null
C. Both A & B
D. Unique

18.Why does this statement cause an error when QUANTITY values are null?
A. The expression attempts to divide by a null value
B. The data types in the conversion function are incompatible
C. The character string none should be enclosed in single quotes (‘ ‘)
D. The expression attempts to divide by a null value

19.The result of which unknown is unknown?
A. Xor
B. Or
C. And
D. Xor

20.Aggregate functions are functions that take a what as input and return a single value?
A. Collection of values
B. Single value
C. Aggregate value
D. Collection of values

21.Which of the following should be used to find the mean of the salary ?
A. Mean(salary)
B. Avg(salary)
C. Sum(salary)
D. Mean(salary)

22.If we do want to eliminate duplicates, we use the keyword in the aggregate expression?
A. Distinct
B. Count
C. Avg
D. Distinct

23.All aggregate functions except ignore null values in their input collection?
A. Count(attribute)
B. Count(*)
C. Avg
D. Count(attribute)

24. A Boolean data type that can take values true, false, and?
A. 1
B. 0
C. Null
D. 1

25.The phrase “greater than at least one” is represented in SQL by?
A. < all
B. < some
C. > all
D. < all

26.We can test for the nonexistence of tuples in a subquery by using the construct?
A. Not exist
B. Not exists
C. Exists
D. Not exist

27.Relational Algebra is a query language that takes two relations as input and produces another relation as an output of the query?
A. Relational
B. Structural
C. Procedural
D. Relational

28.Which of the following is a fundamental operation in relational algebra?
A. Set intersection
B. Natural join
C. Assignment
D. Set intersection

29.Which of the following is used to denote the selection operation in relational algebra?
A. Pi (Greek)
B. Sigma (Greek)
C. Lambda (Greek)
D. Pi (Greek)

30.The which operation, denoted by −, allows us to find tuples that are in one relation but are not in another?
A. Union
B. Set-difference
C. Difference
D. Union


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