Explain whether or not the following statement is true: the join of two tables obtained by a (vertical or horizontal) partitioning of a table, T, can never contain more tuples than are contained in T.
What will be an ideal response?
By join in this exercise, we mean natural join.
1. For a vertically partitioned table, the natural join of all the partitions is exactly the original table. The natural join of some subset of the partitions yields some subset of the table.
2. For a horizonally partitioned table, the natural join of all or any subset of the partitions is an empty table, because each rowof the original table is in exactly one partition.
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What will be an ideal response?
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