COMP9315 22T1 Final Exam The University of New South Wales
COMP9315 DBMS Implementation
22T1 Final Exam 		DBMS Implementation
[Instructions] [PostgreSQL] [C] [Q1-3 Info]
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Question 8 (6 marks)

Consider the following collection of (very unrealistically sized) superimposed codeword page descriptors and their corresponding bit-sliced version. Page desciptors are 10-bits long, and there are 8 pages. Bit-slices are 8-bits long and there are 10 of them. 

Page descriptors         Bit Slices
================         ==========
[0] 0100010110           [0] 01010110
[1] 1000110010           [1] 10100101
[2] 0101010100           [2] 00010110
[3] 1010101010           [3] 00101110
[4] 0001111000           [4] 01011001
[5] 1111000000           [5] 11101001
[6] 1011000001           [6] 00011000
[7] 0100110100           [7] 10100001
                         [8] 11010000
                         [9] 00000010

Given the query descriptor 0100010100 ...

  1. Show how the slice of potentially matching pages is derived.
    Start from a "matching slice" containing 11111111, and show all intermediate values of the matching slice.

  2. State which pages contain potential matches.
    Bit [0] in a slice corresponds to page [0], bit [1] in a slice corresponds to page [1], etc.

State all assumptions. Show all working.

Instructions:

End of Question