Question: Suppose you want to compute A,Bsum(C) on a relation s which is stored partitioned on s.B. Explain how you would do it efficiently, minimizing/avoiding repartitioning,

Suppose you want to compute A,Bγsum(C) on a relation s which is stored partitioned on s.B. Explain how you would do it efficiently, minimizing/avoiding repartitioning, if the number of distinct s.B values is large, and the distribution of number of tuples with each s.B value is relatively uniform.

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