
176 Large Scale and Big Data
access of PigSPARQL. Improvements are still present but less signicant, resulting
in an up to ve times faster query execution.
An open issue of the evaluation remains the actual data ow between HBase
and MapReduce, as HBase is like a black box where data distribution and parti-
tioning is handled by the system automatically. Since data locality is an important
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LUBM (# universities) LUBM (# universities)
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LUBM (# universities) LUBM (# universities)
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