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Unformatted text preview: Advanced Database Systems - CSCI-GA.2434 - Fall 2011 Professor: Dennis Shasha Homework 2 - Due: Tuesday, November 22, 2011 In this assignment, you should do EITHER problems 1 and 2 (worth 20 points each) OR problem 3 (worth 40 points). If you do both, then we will take the max(your problem 1 plus problem 2 scores, problem 3 score). You may work with one partner and sign both of your names to your paper. 1. Design a program in your favorite programming language that can generate tuples where field values can be unique, have a fixed set of distinct values that are allocated to tuples according to a uniform probability distribution, and a fixed set allocated to the tuples according to a fractal probability distribution (70-30 rule). An example function is pseudocode to do this is as follows: gen(frac, N) begin p:= random permutation of numbers from 1 to N outvec:= p // so outvec is of length N while(|p| > 1 p:= first frac*|p| elements of p concatenate p to outvec end while return random permutation of outvec...
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- Spring '11
- Relational model, Random permutation, uniform probability distribution, fractal probability distribution