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  1. Apache Jena
  2. JENA-90

Use OpReduce instead of OpDistinct for DISTINCT + ORDER BY queries

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Details

    • Improvement
    • Status: Closed
    • Trivial
    • Resolution: Done
    • None
    • Jena 2.11.0
    • ARQ

    Description

      ARQ's optimizer could use an OpReduce instead of OpDistinct if a query is DISTINCT + ORDER BY.
      OpReduce removes adjacent duplicates and it does not require a set of already seen bindings as the current OpDistinct implementation does.

      Attachments

        1. ARQ_JENA-90_r1159636.patch
          6 kB
          Paolo Castagna

        Issue Links

          is related to

          New Feature - A new feature of the product, which has yet to be developed. JENA-99 Spill to disk data bags

          • Major - Major loss of function.
          • Closed
          relates to

          Improvement - An improvement or enhancement to an existing feature or task. JENA-89 Avoid a total sort for ORDER BY + LIMIT queries

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Closed

          Activity

            People

              castagna Paolo Castagna
              castagna Paolo Castagna
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              Dates

                Created:
                Updated:
                Resolved: