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  1. Apache Jena
  2. JENA-1815

Join strategy/VarFinder: deal with assigned variables (AS) differently to pattern defined variables.

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Details

    • Improvement
    • Status: Open
    • Major
    • Resolution: Unresolved
    • Jena 3.13.1, Jena 3.14.0
    • None
    • None
    • None

    Description

      The VarFinder treats assigned variables (AS ?var) in the same way as variables set by pattern. In the sense that these two forms both set variables, this is correct but "AS variables" can not be substituted for. At the moment join classification says that a join is not "linear" (i.e. sequence can be used) when assignment is encountered.

      By classifying variables into substituable and non-substitutable, it should be possible to do a better job of optimization choices of the join strategy.

      This is motivated by JENA-1813.

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              andy Andy Seaborne
              andy Andy Seaborne
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                Created:
                Updated: