31. A
data cube C, has n dimensions, and each dimension has exactly p distinct values
in the base cuboid. Assume that there are no concept hierarchies associated
with the dimensions. What is the maximum number of cells possible in the data
cube, C?

(A) p

^{n}(B) p
(C) (2

^{n}-1)p+1 (D) (p+1)^{n}
Answer:
D

**Explanation:**

(a) What is
the maximum number of cells possible in the base cuboid?

p

^{n}.
This is the
maximum number of distinct tuples that you can form with p distinct values per
dimensions.

(b) What is
the minimum number of cells possible in the base cuboid?

p.

You need at
least p tuples to contain p distinct values per dimension. In this case no
tuple shares any value on any dimension.

(c) What is
the minimum number of cells possible in the data cube, C?

(2

^{n}-1)×p+1.
The minimum
number of cells is when each cuboid contains only p cells, except for the apex,
which contains a single cell.

(d) What is
the maximum number of cells possible (including both base cells and aggregate
cells) in the data cube, C?

(p+1)

^{n}.
The argument
is similar to that of part (a), but now we have p+1 because in addition to the
p distinct values of each dimension we can also choose ∗.

32. Suppose
that from given statistics, it is known that meningitis causes stiff neck 50%
of the time, that the proportion of persons having meningitis is 1/50000, and
that the proportion of people having stiff neck is 1/20. Then the percentage of
people who had meningitis and complain about stiff neck is:

(A) 0.01% (B) 0.02%

(C) 0.04% (D) 0.05%

Answer:
B

**Explanation:**

The
computation is based on the simplified Bayes’ formula.

P{B|A} = (P{A|B}·P{B)
/ P{A}.

P{M|S} =
probability that a person had meningitis, conditioned by the existence of stiff
neck.

P{S|M} =
probability that a person complains about stiff neck, conditioned by the
existence of meningitis. = 50%=1/2

P{S} =
proportion of people who complain about stiff neck. = 1/20

P{M} =
proportion of people who had meningitis. = 1/50,000

Then:

P{M|S} =
(P{S|M}·P{M}) / P{S} =(

^{1}/_{2}x^{1}/_{50,000}) /^{1}/_{20 }= 0.0002 = 0.02%
33. .................
system is market oriented and is used for data analysis by knowledge workers
including Managers, Executives and Analysts.

(A) OLTP (B) OLAP

(C) Data
System (D) Market System

Answer:
B

34. ..................
allows selection of the relevant information necessary for the data warehouse.

(A) The
Top-Down View (B) Data Warehouse
View

(C) Data
source View (D) Business Query
View

Answer:
A

35. The
hash function used in double hashing is of the form:

(A) h(k, i)=(h

_{1}(k)+h_{2}(k)+i)mod m (B) h(k, i)=(h_{1}(k)+h_{2}(k)-i)mod m
(C) h(k,
i)=(h

_{1}(k)+ih_{2}(k))mod m (D) h(k, i)=(h_{1}(k)-ih_{2}(k))mod m
Answer:
C

36. In
the following graph, discovery time stamps and finishing time stamps of Depth
First Search (DFS) are shown as x/y where x is discovery time stamp and y is
finishing time stamp.

It shows
which of the following depth first forest?

(A) {a,b,e}
{c,d,f,g,h} (B) {a,b,e}
{c,d,h} {f,g}

(C) {a,b,e}
{f,g} {c,d} {h} (D) {a,b,c,d}
{e,f,g} {h}

Answer: A

37. The
number of disk pages access in B-tree search, where h is height, n is the
number of keys, and t is the minimum degree, is:

(A) Î¸(log

_{n}h*t) (B) Î¸(log_{t}n*h)
(C) Î¸(log

_{h}n) (D) Î¸(log_{t}n)
Answer:
D

38. The
inorder traversal of the following tree is:

(A) 2 3 4 6
7 13 15 17 18 18 20

(B) 20 18 18
17 15 13 7 6 4 3 2

(C) 15 13 20
4 7 17 18 2 3 6 18

(D) 2 4 3 13
7 6 15 17 20 18 18

Answer:
D

39. An
ideal sort is an in-place-sort whose additional space requirement is
...............

(A) O(log

_{2}n) (B) O(nlog_{2}n)
(C) O(1) (D) O(n)

Answer:
C

40. Which
of the following is not a congestion policy at network layer?

(A) Flow
Control Policy

(B) Packet
Discard Policy

(C) Packet
Lifetime Management Policy

(D) Routing
Algorithm

Answer:
A

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