Welcome to DataBase Quiz, Advanced Level !!

Question 1. Which of the following is true of a network structure?

It is a physical representation of the data

It allows a many-to-many relationship

It is conceptually simple

It will be dominant data base of the future

Question 2. Given the following relation instance.
x  y  z
1  4  2
1  5  3
1  6  3
3  2  2 
Which of the following functional dependencies are satisfied by the instance?

XY -> Z and Z -> Y

YZ -> X and Y -> Z

YZ -> X and X -> Z

XZ -> Y and Y -> X

Question 3. What will be the output of the following statement? SELECT STR(6365, 3)

***

6365

6,365

6400

Question 4. What will be the output of the following statement? SET ARITHABORT OFF SET ANSI_WARNINGS OFF SELECT 100/0

Null

0

Infinity

Error

Question 5. What type of lock will deny users any access to a table?

EXPLICIT

IMPLICIT

EXCLUSIVE

READ ONLY

Question 6. In SQL, relations can contain null values, and comparisons with null values are treated as unknown. Suppose all comparisons with a null value are treated as false. Which of the following pairs is not equivalent?

x = 5, not (not (x = 5))

x = 5, x > 4 and x < 6, where x is an integer

x < 5, not(x = 5)

none of the above

Question 7. The highest level in the hierarchy of data organization is called

data bank

data base

data file

data record

Question 8. Given the relations
employee (name, salary, deptno) and department (deptno, deptname, address)
Which of the following queries cannot be expressed using the basic relational algebra operations (U, -, x, , p)?

Department address of every employee

Employees whose name is the same as their department name

The sum of all employees? salaries

All employees of a given department

Question 9. Consider a schema R(A, B, C, D) and functional dependencies A -> B and C -> D. Then the decomposition of R into R1 (A, B) and R2(C, D) is

dependency preserving and loss less join

loss less join but not dependency preserving

dependency preserving but not loss less join

not dependency preserving and not loss less join

Question 10. What will be the output of the following statement? SELECT ROUND(123.89, -1)

120.00

123.00

123.90

124.00