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  1. Blazegraph (by SYSTAP)
  2. BLZG-1108

GROUP BY optimization using distinct-term-scan and fast-range-count

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      The following query can be rewritten to use the distinct term scan (to produce the bindings for ?z) and then a group-by over the fast-range counts for the as-bound values of ?x rdf:type ?z. This would take the runtime cost from on the order of 4-8 seconds for a large data set to the order of a few 10s of milliseconds.

      SELECT  (COUNT(*) as ?count) ?z WHERE {  ?x rdf:type ?z  } GROUP BY ?z;
      

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            Assignee:
            michaelschmidt michaelschmidt
            Reporter:
            bryanthompson bryanthompson
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