我是 SPARQL 1.1 的初学者。我有一个如下所示的 N-Triples 文件。Work_RVU
我想找到(最后一个属性)和相关代码(第 4 个属性)的最大值。
<file://PPRVU12.xlsx/69540> <http://www.w3.org/1999/02/22-rdf-syntax-ns?#type> <http://cms.gov/HCPCS> .
<file://PPRVU12.xlsx/69540> <http://www.w3.org/2000/01/rdf-schema#label> "Remove ear lesion" .
<file://PPRVU12.xlsx/69540> <file://PPRVU12.xlsx#Status_Code> "A" .
<file://PPRVU12.xlsx/69540> <file://PPRVU12.xlsx#Code> "69540" .
<file://PPRVU12.xlsx/69540> <file://PPRVU12.xlsx#Work_RVU> "1.25" .
<file://PPRVU12.xlsx/69550> <http://www.w3.org/1999/02/22-rdf-syntax-ns?#type> <http://cms.gov/HCPCS> .
<file://PPRVU12.xlsx/69550> <http://www.w3.org/2000/01/rdf-schema#label> "Remove ear lesion" .
<file://PPRVU12.xlsx/69550> <file://PPRVU12.xlsx#Status_Code> "A" .
<file://PPRVU12.xlsx/69550> <file://PPRVU12.xlsx#Code> "69550" .
<file://PPRVU12.xlsx/69550> <file://PPRVU12.xlsx#Work_RVU> "11.15" .
<file://PPRVU12.xlsx/69552> <http://www.w3.org/1999/02/22-rdf-syntax-ns?#type> <http://cms.gov/HCPCS> .
<file://PPRVU12.xlsx/69552> <http://www.w3.org/2000/01/rdf-schema#label> "Remove ear lesion" .
<file://PPRVU12.xlsx/69552> <file://PPRVU12.xlsx#Status_Code> "A" .
<file://PPRVU12.xlsx/69552> <file://PPRVU12.xlsx#Code> "69552" .
<file://PPRVU12.xlsx/69552> <file://PPRVU12.xlsx#Work_RVU> "19.81" .
最大 RVU 应为 19.81,代码应为“69552”。我可以打印 19.81 但总是打印“69540”,这意味着它总是选择每次遇到的第一个代码。
我的 SPARQL 代码如下:
PREFIX pre: <file://PPRVU12.xlsx#>
SELECT ?code (MAX (?val) AS ?Max_RVU)
WHERE{
?code pre:Work_RVU ?val .
}
这个查询有错误吗?我还尝试了另一个查询,
PREFIX pre: <file://PPRVU12.xlsx#>
PREFIX head: <http://www.w3.org/1999/02/22-rdf-syntax-ns?#>
SELECT ?code (MAX (?val) AS ?Max_RVU)
WHERE{
?d head:type <http://cms.gov/HCPCS> .
?d pre:Code ?code .
?d pre:Work_RVU ?val .
}
但结果是一样的。