过滤SPARQL结果

Question

我具有以下示例三元组

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

由于参数i使用WORD1和WORD2。我想所有的词含。 WORD1和WORD2，它发生与WORD1和WORD2在一起。

从这个例子的结果必须是：

word1
word2
word3
word4

我真的不知道，如何让这样的：（

Answer 1

假设谓词name是所有words相同，并且没有其他三元组与name谓词：

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

---

编辑的问题被编辑后：

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