UGC NET CS 2016 July – III

Question 11

Consider the following ORACLE relations : R (A, B, C) = {<1, 2, 3>, <1, 2, 0>, <1, 3, 1>, <6, 2, 3>, <1, 4, 2>, <3, 1, 4> } S (B, C, D) = {<2, 3, 7>, <1, 4, 5>, <1, 2, 3>, <2, 3, 4>, <3, 1, 4>}. Consider the following two SQL queries SQ₁ and SQ₂ : SQ₁ : SELECT R⋅B, AVG (S⋅B) FROM R, S WHERE R⋅A = S⋅C AND S⋅D < 7 GROUP BY R⋅B;
SQ₂ : SELECT DISTINCT S⋅B, MIN (S⋅C) FROM S GROUP BY S⋅B HAVING COUNT (DISTINCT S⋅D) > 1; If M is the number of tuples returned by SQ₁ and N is the number of tuples returned by SQ₂ then

• M = 4, N = 2
• M = 5, N = 3
• M = 2, N = 2
• M = 3, N = 3

Question 12

Semi-join strategies are techniques for query processing in distributed database system. Which of the following is a semi-join technique ?

• Only the joining attributes are sent from one site to another and then all of the rows are returned.
• All of the attributes are sent from one site to another and then only the required rows are returned.
• Only the joining attributes are sent from one site to another and then only the required rows are returned.
• All of the attributes are sent from one site to another and then only the required rows are returned.

Question 13

Consider the Breshenham’s circle generation algorithm for plotting a circle with centre (0, 0) and radius ‘r’ units in first quadrant. If the current point is (x_i , y_i ) and decision parameter is p_i then what will be the next point (x_{i + 1}, y_{i + 1} + 1) and updated decision parameter p_{i + 1} for p_i ≥ 0?

• x_{i + 1} = x_i+ 1 y_{i + 1} = y_i p_{i + 1} = p_i + 4x_i + 6
• x_{i + 1} = x_i + 1 y_{i + 1} = y_i - 1 p_{i + 1} = p_i + 4(x_i - y_i) + 10
• x_{i + 1} = x_i y_{i + 1} = y_i - 1 p_{i + 1} = p_i + 4(x_i - y_i) + 6
• x_{i + 1} = x_i - 1 y_{i + 1} = y_i p_{i + 1} = p_i + 4(x_i - y_i) + 10

Question 14

A point P(5, 1) is rotated by 90° about a pivot point (2, 2). What is the coordinate of new transformed point P′ ?

• (3, 5)
• (5, 3)
• (2, 4)
• (1, 5)

Question 15

Let R be the rectangular window against which the lines are to be clipped using 2D Sutherland-Cohen line clipping algorithm. The rectangular window has lower left-hand corner at (– 5, 1) and upper right-hand corner at (3, 7). Consider the following three lines for clipping with the given end point co-ordinates: Line AB : A (– 6, 2) and B (–1, 8) Line CD : C (– 1, 5) and D (4, 8) Line EF : E (–2, 3) and F (1, 2) Which of the following line(s) is/are candidate for clipping?

• AB
• CD
• EF
• AB and CD

Question 16

In perspective projection, if a line segment joining a point which lies in front of the viewer to a point in back of the viewer is projected to a broken line of infinite extent. This is known as _______.

• View confusion
• Vanishing point
• Topological distortion
• Perspective foreshortening

Question 17

Let us consider that the original point is (x, y) and new transformed point is (x′, y′). Further, Sh_x and Sh_y are shearing factors in x and y directions. If we perform the y-direction shear relative to x = x_ref then the transformed point is given by _______.

• x′ = x + Sh_x ⋅ (y – y_ref) y′ = y
• x′ = x y′ = y ⋅ Sh_x
• x′ = x y′ = Sh_y (x – x_ref) + y
• x′ = Sh_y ⋅ y y′ = y ⋅ (x – x_ref)

Question 18

Which of the following statement(s) is/are correct with reference to curve generation? I. Hermite curves are generated using the concepts of interpolation. II. Bezier curves are generated using the concepts of approximation. III. The Bezier curve lies entirely within the convex hull of its control points. IV. The degree of Bezier curve does not depend on the number of control points.

• I, II and IV only
• II and III only
• I and II only
• I, II and III only

Question 19

Given the following statements: 
(A) To implement Abstract Data Type, a programming language require a syntactic unit to encapsulate type definition. 
(B) To implement ADT, a programming language requires some primitive operations that are built in the language processor. 
(C) C++, Ada, Java 5.0, C#2005 provide support for parameterized ADT. 
Which one of the following options is correct ?

• (A), (B) and (C) are false.
  

• (A) and (B) are true; (C) is false.
  

• (A) is true; (B) and (C) are false.
  

• (A), (B) and (C) are true.
  

Question 20

Match the following types of variables with the corresponding programming languages:

• (1)
• (2)
• (3)
• (4)