基于邮政编码第一部分的 HM 土地登记站点上的 SPARQL 查询

问题描述

我正在尝试通过 https://landregistry.data.gov.uk/app/qonsole 使用 HM Land Registry 开放数据 SPARQL 查询找出邮政编码区域的平均房价数据，如果是邮政编码部门（例如 GL52），最好的方法是什么)？

那里给出的“邮政编码中的交易”示例代码显示了如何搜索完整的邮政编码，我尝试在 VALUES 上使用 STRSTARTS() 更改代码？邮政编码部分，但它返回一个错误..

prefix rdf: <http://www.w3.org/1999/02/22-rdf-Syntax-ns#>
prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix owl: <http://www.w3.org/2002/07/owl#>
prefix xsd: <http://www.w3.org/2001/XMLSchema#>
prefix sr: <http://data.ordnancesurvey.co.uk/ontology/spatialrelations/>
prefix ukhpi: <http://landregistry.data.gov.uk/def/ukhpi/>
prefix lrppi: <http://landregistry.data.gov.uk/def/ppi/>
prefix skos: <http://www.w3.org/2004/02/skos/core#>
prefix lrcommon: <http://landregistry.data.gov.uk/def/common/>

# Returns the Price Paid data from the default graph for each transaction record having
# an address with the given postcode.
# The postcode to query is set using SPARQL 1.1's 'values' clause

SELECT ?paon ?saon ?street ?town ?county ?postcode ?amount ?date ?category
WHERE
{
  VALUES ?postcode STRSTARTS({"GL52"^^xsd:string},{"GL52"^^xsd:string})

  ?addr lrcommon:postcode ?postcode.

  ?transx lrppi:propertyAddress ?addr ;
          lrppi:pricePaid ?amount ;
          lrppi:transactionDate ?date ;
          lrppi:transactionCategory/skos:prefLabel ?category.

  OPTIONAL {?addr lrcommon:county ?county}
  OPTIONAL {?addr lrcommon:paon ?paon}
  OPTIONAL {?addr lrcommon:saon ?saon}
  OPTIONAL {?addr lrcommon:street ?street}
  OPTIONAL {?addr lrcommon:town ?town}
}
ORDER BY ?amount

错误返回为 在第 18 行第 20 列遇到““STRSTARTS”“STRSTARTS””。 期待： "{" ...

任何建议将不胜感激！

解决方法

恐怕你的语法是错误的。对于此类查询，您需要一个过滤器，例如：

prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix owl: <http://www.w3.org/2002/07/owl#>
prefix xsd: <http://www.w3.org/2001/XMLSchema#>
prefix sr: <http://data.ordnancesurvey.co.uk/ontology/spatialrelations/>
prefix ukhpi: <http://landregistry.data.gov.uk/def/ukhpi/>
prefix lrppi: <http://landregistry.data.gov.uk/def/ppi/>
prefix skos: <http://www.w3.org/2004/02/skos/core#>
prefix lrcommon: <http://landregistry.data.gov.uk/def/common/>

# Returns the Price Paid data from the default graph for each transaction record having
# an address with the given postcode.
# The postcode to query is set using SPARQL 1.1's 'values' clause

    SELECT ?paon ?saon ?street ?town ?county ?postcode ?amount ?date ?category
    WHERE
    {
      ?addr lrcommon:postcode ?postcode .
    
      ?transx lrppi:propertyAddress ?addr ;
              lrppi:pricePaid ?amount ;
              lrppi:transactionDate ?date ;
              lrppi:transactionCategory/skos:prefLabel ?category.
      FILTER(STRSTARTS(?postcode,"GL52")) #Difference is here
    
      OPTIONAL {?addr lrcommon:county ?county}
      OPTIONAL {?addr lrcommon:paon ?paon}
      OPTIONAL {?addr lrcommon:saon ?saon}
      OPTIONAL {?addr lrcommon:street ?street}
      OPTIONAL {?addr lrcommon:town ?town}
    }
    ORDER BY ?amount

现在，这个端点不是最快的，所以这个查询会很遗憾地超时。您可以通过指定县是什么来提高查询性能，以下查询也将产生您所追求的（并且不会超时）：

prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix owl: <http://www.w3.org/2002/07/owl#>
prefix xsd: <http://www.w3.org/2001/XMLSchema#>
prefix sr: <http://data.ordnancesurvey.co.uk/ontology/spatialrelations/>
prefix ukhpi: <http://landregistry.data.gov.uk/def/ukhpi/>
prefix lrppi: <http://landregistry.data.gov.uk/def/ppi/>
prefix skos: <http://www.w3.org/2004/02/skos/core#>
prefix lrcommon: <http://landregistry.data.gov.uk/def/common/>

# Returns the Price Paid data from the default graph for each transaction record having
# an address with the given postcode.
# The postcode to query is set using SPARQL 1.1's 'values' clause

SELECT ?paon ?saon ?street ?town ?county ?postcode ?amount ?date ?category
WHERE
{
  #VALUES ?pc {"GL52"}

  ?addr lrcommon:postcode ?postcode ;
        lrcommon:county "GLOUCESTERSHIRE" .

  ?transx lrppi:propertyAddress ?addr ;
          lrppi:pricePaid ?amount ;
          lrppi:transactionDate ?date ;
          lrppi:transactionCategory/skos:prefLabel ?category.
  FILTER(STRSTARTS(?postcode,"GL52"))

  #OPTIONAL {?addr lrcommon:county ?county}
  OPTIONAL {?addr lrcommon:paon ?paon}
  OPTIONAL {?addr lrcommon:saon ?saon}
  OPTIONAL {?addr lrcommon:street ?street}
  OPTIONAL {?addr lrcommon:town ?town}
}
ORDER BY ?amount

现在，如果您想同时查看多个邮政编码，您可以试试这个：

prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix owl: <http://www.w3.org/2002/07/owl#>
prefix xsd: <http://www.w3.org/2001/XMLSchema#>
prefix sr: <http://data.ordnancesurvey.co.uk/ontology/spatialrelations/>
prefix ukhpi: <http://landregistry.data.gov.uk/def/ukhpi/>
prefix lrppi: <http://landregistry.data.gov.uk/def/ppi/>
prefix skos: <http://www.w3.org/2004/02/skos/core#>
prefix lrcommon: <http://landregistry.data.gov.uk/def/common/>

# Returns the Price Paid data from the default graph for each transaction record having
# an address with the given postcode.
# The postcode to query is set using SPARQL 1.1's 'values' clause

SELECT ?paon ?saon ?street ?town ?county ?postcode ?amount ?date ?category
WHERE
{
  VALUES ?pc {"GL52" "GL51" "GL1 "}

  ?addr lrcommon:postcode ?postcode ;
        lrcommon:county "GLOUCESTERSHIRE" .

  ?transx lrppi:propertyAddress ?addr ;
          lrppi:pricePaid ?amount ;
          lrppi:transactionDate ?date ;
          lrppi:transactionCategory/skos:prefLabel ?category.
  FILTER(STRSTARTS(?postcode,?pc))

  #OPTIONAL {?addr lrcommon:county ?county}
  OPTIONAL {?addr lrcommon:paon ?paon}
  OPTIONAL {?addr lrcommon:saon ?saon}
  OPTIONAL {?addr lrcommon:street ?street}
  OPTIONAL {?addr lrcommon:town ?town}
}
ORDER BY ?amount

这是在做同样的事情，但本质上是一个缩写。