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JenaARQ 执行的优化之一是：“将过滤器放置在定义其依赖变量的位置附近”。

这会导致以下查询计划：

  (filter (exprlist (|| (|| (isIRI ?Y) (isBlank ?Y)) (!= (datatype ?Y) <http://example.com/onto/rdf#structure>)) (|| (|| (isIRI ?Z) (isBlank ?Z)) (!= (datatype ?Z) <http://example.com/onto/rdf#structure>)))
    (bgp
      (triple ?X <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://swat.cse.lehigh.edu/onto/univ-bench.owl#Student>)
      (triple ?Y <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://swat.cse.lehigh.edu/onto/univ-bench.owl#Faculty>)
      (triple ?Z <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://swat.cse.lehigh.edu/onto/univ-bench.owl#Course>)
      (triple ?X <http://swat.cse.lehigh.edu/onto/univ-bench.owl#advisor> ?Y)
      (triple ?Y <http://swat.cse.lehigh.edu/onto/univ-bench.owl#teacherOf> ?Z)
      (triple ?X <http://swat.cse.lehigh.edu/onto/univ-bench.owl#takesCourse> ?Z)
    )))

转化为以下内容：

  (sequence
    (filter (|| (|| (isIRI ?Z) (isBlank ?Z)) (!= (datatype ?Z) <http://example.com/onto/rdf#structure>))
      (sequence
        (filter (|| (|| (isIRI ?Y) (isBlank ?Y)) (!= (datatype ?Y) <http://example.com/onto/rdf#structure>))
          (bgp
            (triple ?X <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://swat.cse.lehigh.edu/onto/univ-bench.owl#Student>)
            (triple ?Y <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://swat.cse.lehigh.edu/onto/univ-bench.owl#Faculty>)
          ))
        (bgp (triple ?Z <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://swat.cse.lehigh.edu/onto/univ-bench.owl#Course>))))
    (bgp
      (triple ?X <http://swat.cse.lehigh.edu/onto/univ-bench.owl#advisor> ?Y)
      (triple ?Y <http://swat.cse.lehigh.edu/onto/univ-bench.owl#teacherOf> ?Z)
      (triple ?X <http://swat.cse.lehigh.edu/onto/univ-bench.owl#takesCourse> ?Z)
    )))

事实证明，虽然原始查询计划以毫秒为单位运行，但“优化”查询计划需要大约 7 个小时才能完成。

JenaARQ 是否考虑任何用于优化查询计划中的过滤器位置的统计信息？

我正在使用耶拿 3.12.0。

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