Suppose we take a star join of a fact table F(A1, A2, ..., Am) with dimension tables
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Suppose we take a star join of a fact table F(A1, A2, ..., Am) with dimension tables Di(Ai, Bi) for i = 1, 2, ..., m. Let there be k Reduce tasks, each associated with a vector of buckets, one for each of the key attributes A1, A2, ..., Am. Suppose the number of buckets into which we hash A; is aj. Naturally, ajaz...am = k. Finally, suppose each dimension table Di has size di, and the size of the fact table is much larger than any of these sizes. Find the values of the a's that minimize the cost of taking the star join as one map-reduce operation.
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Quantitative Investment Analysis
ISBN: 978-1119104223
3rd edition
Authors: Richard A. DeFusco, Dennis W. McLeavey, Jerald E. Pinto, David E. Runkle
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