Question

我正在尝试查询所有机场及其IATA代码的列表：

PREFIX p: <http://dbpedia.org/property/>
PREFIX o: <http://dbpedia.org/ontology/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

SELECT DISTINCT ?airport ?iata ?name 
WHERE {
    ?airport rdf:type o:Airport ;
     p:iata ?iata ;
     p:name ?name 
}
ORDER by ?airport

Executing it看起来很好，但是有一些奇怪的街区，机场被分配了错误的名称，例如：

http://dbpedia.org/resource/Prince_Abdul_Majeed_bin_Abdul_Aziz_Domestic_Airport  "ULH"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en
http://dbpedia.org/resource/Prince_Albert_(Glass_Field)_Airport                  "YPA"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en
http://dbpedia.org/resource/Prince_George_Airport                                "YXS"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en
http://dbpedia.org/resource/Prince_Mohammad_Bin_Abdulaziz_Airport                "MED"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en
http://dbpedia.org/resource/Prince_Rupert/Seal_Cove_Water_Airport                "ZSW"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en
http://dbpedia.org/resource/Prince_Rupert_Airport                                "YPR"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en
http://dbpedia.org/resource/Prince_Said_Ibrahim_International_Airport            "HAH"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en
http://dbpedia.org/resource/Princess_Juliana_International_Airport               "SXM"@en   "Prince Abdul Majeed bin Abdul Aziz Airport"@en

除了名字中都有“王子”外，他们似乎没有任何共同点。单击该资源也表明与他们已分配的名称无关。

我做错了什么？

编辑 - 找到解决方案：

删除“按机场排序”或将其更改为“按订单排序？iata”可解决此问题。

Answer 1

DBpedia本体（dbpedia-owl）数据往往比旧的信息框数据（dbprop）更清晰，所以我想您可能想要使用使用{{1}的查询} properties：

dbpedia-owl

SPARQL Results

数据稍好一些，但仍然有一些奇怪的结果，如：

SELECT ?airport ?iata ?name
WHERE {
    ?airport a dbpedia-owl:Airport ;
             dbpedia-owl:iataLocationIdentifier ?iata ;
             rdfs:label ?name .
    FILTER langMatches( lang( ?name ), "EN" )
}
order by ?airport

为了尝试一些不同的方法，我还决定尝试按http://dbpedia.org/resource/Prince_Albert_(Glass_Field)_Airport "YPA"@en "Prince Albert (Glass Field) Airport"@en http://dbpedia.org/resource/Prince_George_Airport "YXS"@en "Prince Albert (Glass Field) Airport"@en http://dbpedia.org/resource/Prince_Mohammad_Bin_Abdulaziz_Airport "MED"@en "Prince Albert (Glass Field) Airport"@en http://dbpedia.org/resource/Prince_Rupert/Seal_Cove_Water_Airport "ZSW"@en "Prince Albert (Glass Field) Airport"@en http://dbpedia.org/resource/Prince_Rupert_Airport "YPR"@en "Prince Albert (Glass Field) Airport"@en http://dbpedia.org/resource/Prince_Said_Ibrahim_International_Airport "HAH"@en "Prince Albert (Glass Field) Airport"@en http://dbpedia.org/resource/Princess_Juliana_International_Airport "SXM"@en "Prince Albert (Glass Field) Airport"@en http://dbpedia.org/resource/Princeton_Airport_(New_Jersey) "PCT"@en "Prince Albert (Glass Field) Airport"@en和?airport进行分组，然后对名称进行抽样：

?iata

SPARQL Results

这有所不同，但结果同样奇怪，例如：

SELECT ?airport ?iata sample(?name)
WHERE {
    ?airport a dbpedia-owl:Airport ;
             dbpedia-owl:iataLocationIdentifier ?iata ;
             rdfs:label ?name .
    FILTER langMatches( lang( ?name ), "EN" )
}
group by ?airport ?iata
order by ?airport

然而，如果我们按名称分组，并选择名称并计算具有给定名称的机场数量，我们会全面获得http://dbpedia.org/resource/%22Solidarity%22_Szczecin-Goleni%C3%B3w_Airport "SZZ"@en ""Solidarity" Szczecin-Goleniów Airport"@en http://dbpedia.org/resource/%C3%81ngel_Albino_Corzo_International_Airport "TGZ"@en ""Solidarity" Szczecin-Goleniów Airport"@en http://dbpedia.org/resource/%C3%84ngelholm-Helsingborg_Airport "AGH"@en ""Solidarity" Szczecin-Goleniów Airport"@en http://dbpedia.org/resource/%C3%85lesund_Airport,_Vigra "AES"@en ""Solidarity" Szczecin-Goleniów Airport"@en http://dbpedia.org/resource/%C3%85re_%C3%96stersund_Airport "OSD"@en ""Solidarity" Szczecin-Goleniów Airport"@en，但会出现一些名称两次！

SPARQL Results

SELECT count(?airport) ?name
WHERE {
    ?airport a dbpedia-owl:Airport ;
             dbpedia-owl:iataLocationIdentifier ?iata ;
             rdfs:label ?name .
    FILTER langMatches( lang( ?name ), "EN" )
}
group by ?name
order by ?name

这真的很奇怪。看起来你的查询没有任何问题，但是在DBpedia上发生了一些奇怪的事情。您可以查看其中一些奇怪的条目，DBpedia将显示的数据与这些结果不匹配。例如，原始查询的结果之一是

1   "Abraham González International Airport"@en
1   "Abraham González International Airport"@en
...
1   "Prince Albert (Glass Field) Airport"@en
1   "Prince Albert (Glass Field) Airport"@en
1   "Prince Albert (Glass Field) Airport"@en
1   "Prince Albert (Glass Field) Airport"@en
1   "Prince Albert (Glass Field) Airport"@en
1   "Prince Albert (Glass Field) Airport"@en
1   "Prince Albert (Glass Field) Airport"@en
1   "Prince Albert (Glass Field) Airport"@en

但是如果您访问http://dbpedia.org/page/Prince_Mohammad_Bin_Abdulaziz_Airport并在页面中搜索“Albert”，那么您将无法找到它。

来自DBPedia的奇怪结果

1 个答案: