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我有以下示例三元组

r1 -> property -> resourceA
r1 -> property -> resourceB
r1 -> property -> resourceC
resourceA -> name -> word1
resourceB -> name -> word2
resourceC -> name -> word4

r2 -> property -> resourceD
r2 -> property -> resourceE
r2 -> property -> resourceF
resourceD -> name -> word1
resourceE -> name -> word2
resourceF -> name -> word3

r3 -> property -> resourceG
r3 -> property -> resourceH
r3 -> property -> resourceI
resourceG -> name -> word5
resourceH -> name -> word6
resourceI -> name -> word7

作为参数，我使用 word1 和 word2。我想得到所有的话，包括。word1 和 word2，与 word1 和 word2 一起出现。

此示例的结果必须是：

word1
word2
word3
word4

我真的不知道怎么做这个:(

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1 回答 1

2

假设name所有 s 的谓词都相同，word并且该谓词没有其他三元组name：

SELECT DISTINCT ?w {
  ?s <name> ?w
}
ORDER BY ?w

编辑问题后编辑：

SELECT DISTINCT ?w {  # select each word only once

  # match three properties under the same resource
  ?r <property> ?p1, ?p2, ?p3.

  # two of the properties must have names "word1" and "word2"
  ?p1 <name> "word1" .
  ?p2 <name> "word2" .

  # third property name may be anything, including "word1" and "word2"
  ?p3 <name> ?w .
}
ORDER BY ?w  # return words in sorted order
于 2009-08-04T11:00:30.673 回答