semantic-web - SPARQL 查询 : how to get line and char number from EARL document?

Question

这可能是一个相当新手的问题，但 RDF 图和 sparql 查询让我很困惑。这是我需要搜索的(EARL，评估和报告语言)RDF 文件的相关部分:

<earl:Assertion>
<earl:subject rdf:nodeID="A1"/>
<earl:assertedBy rdf:nodeID="A2"/>
<earl:test rdf:resource="http://www.w3.org/TR/xhtml1/#C_2"/>
<earl:mode rdf:resource="http://www.w3.org/ns/earl#automatic"/>
<earl:result>
  <earl:TestResult>
    <earl:pointer>
      <pnt:EquivalentPointers>
        <pnt:groupPointer>
          <pnt:LineCharPointer>
            <pnt:charNumber rdf:datatype="http://www.w3.org/2001/XMLSchema#positiveInteger"
            >108</pnt:charNumber>
            <pnt:lineNumber rdf:datatype="http://www.w3.org/2001/XMLSchema#positiveInteger"
            >9</pnt:lineNumber>
          </pnt:LineCharPointer>
        </pnt:groupPointer>
        <pnt:groupPointer>
          <pnt:CharOffsetPointer>
            <pnt:offset rdf:datatype="http://www.w3.org/2001/XMLSchema#positiveInteger"
            >935</pnt:offset>
          </pnt:CharOffsetPointer>
        </pnt:groupPointer>
      </pnt:EquivalentPointers>
    </earl:pointer>
    <earl:outcome rdf:resource="http://www.w3.org/ns/earl#failed"/>
    <dct:description rdf:datatype="http://www.w3.org/2001/XMLSchema#string"
    >A space character is missing before '/&gt;'.</dct:description>
  </earl:TestResult>
</earl:result>
</earl:Assertion>

我想从这段摘录中得到什么:lineNumber(和 charNumber)， earl:outcome 失败的事实，以及描述。到目前为止，我所能得到的只是行号，结果却给出了行号+“^^ http://www.w3.org/2001/XMLSchema#positiveInteger”。我不知道为什么会这样。

感谢您的帮助!

Answer 1

以下查询从您的示例中提取所有失败的结果(请注意，我必须为 pnt: 构建一个 URI，因为您没有说明它是什么，而且它没有在 prefix.cc 处列出):

prefix pnt: <http://example.org/pnt#>
prefix earl: <http://www.w3.org/ns/earl#>
prefix dct: <http://purl.org/dc/terms/>

select ?result ?desc ?charNo ?lineNo {
  ?assert a earl:Assertion;
          earl:result ?result.

  ?result earl:outcome earl:failed;
          earl:pointer/pnt:groupPointer ?gpt;
          dct:description ?desc.

  ?gpt pnt:charNumber ?charNo;
       pnt:lineNumber ?lineNo.
}

此查询以纯文本形式给出以下结果:

$ arq --graph=./src/main/resources/earl.rdf --file=./src/main/resources/earl.sparql
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| result | desc                                                                                              | charNo                                                    | lineNo                                                  |
====================================================================================================================================================================================================================================
| _:b0   | "A space character is\n          missing before '/>'."^^<http://www.w3.org/2001/XMLSchema#string> | "108"^^<http://www.w3.org/2001/XMLSchema#positiveInteger> | "9"^^<http://www.w3.org/2001/XMLSchema#positiveInteger> |
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

根据您提供的 RDF 样本，您想要的两个数字是 XSD 类型的数据类型。 ^^ 修饰使用 Turtle 语法简单地表达数据类型。如果我们改为选择 JSON 输出，您可以清楚地看到这一点:

$ arq --graph=./src/main/resources/earl.rdf --file=./src/main/resources/earl.sparql --results=json
{
  "head": {
    "vars": [ "result" , "desc" , "charNo" , "lineNo" ]
  } ,
  "results": {
    "bindings": [
      {
        "result": { "type": "bnode" , "value": "b0" } ,
        "desc": { "datatype": "http://www.w3.org/2001/XMLSchema#string" , "type": "typed-literal" , "value": "A space character is\n          missing before '/>'." } ,
        "charNo": { "datatype": "http://www.w3.org/2001/XMLSchema#positiveInteger" , "type": "typed-literal" , "value": "108" } ,
        "lineNo": { "datatype": "http://www.w3.org/2001/XMLSchema#positiveInteger" , "type": "typed-literal" , "value": "9" }
      }
    ]
  }
}