JUNE 2012 - PAPER III

7. Match the following:
(i)  OLAP     (a) Regression
(ii) OLTP     (b) Data Warehouse
(iii) Decision Tree    (c) RDBMS
(iv) Neural networks    (d) Classification
       (i)   (ii) (iii) (iv)

(A)  (b)  (b)  (c)  (c)

(B)  (c)   (c)  (b)  (b)

(C)  (a)   (d)  (d)  (a) 
(D)  (a)   (d)  (d)  (a) 

Ans:-B

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8. Which level of Abstraction describes what data are stored in the Database ?
   
   1. (A)  Physical level
      
   2. (B)  View level
      
   3. (C)  Abstraction level
   4. (D)  Logical level

Ans:-D

Explanation:-

There are three levels of abstraction.

(i) Physical level - Describes how data are stored

(ii) Logical level - Describes what data are stored in the database and what relationship among those data.

(iii) View level - The highest level of abstraction and describes part of entire database.

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9. The problem that occurs when one transaction updates a database item and then the transaction fails for some reason is ________.

(A)  Temporary Select Problem

(B)  Temporary Modify Problem

(C)  Dirty Read Problem

(D)  None 

Ans:- C

Explanation:-

When one transaction updates a database item and then the transaction fails for some reason, it is called Dirty Read problem or Transaction update problem.

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