使用 Optics API 进行地理空间查询 (MarkLogic)

Question

问题来自thread。我目前正在尝试使用 Optics API 使用 SPARQL 和 CTS 进行搜索。我尝试尝试使用以下代码

查询已使用

import module namespace op="http://marklogic.com/optic" at "/MarkLogic/optic.xqy";
let $people := op:from-lexicons(
  map:entry("people",cts:uri-reference()),
  "lexicon"
)=>op:where(
     cts:path-geospatial-query("people_data/location",
    cts:circle(7500, cts:point(89.39101918779838, 51.97989163203445)),
    "type=long-lat-point")
  )

let $questions := op:from-sparql('SELECT * WHERE {?person </has_dob> ?dob. }', "sparql")

return $questions  => op:join-inner(
    $people,
    op:on(
      op:view-col("lexicon","people"),
      op:view-col("sparql", "person")
    )
  ) => op:result()

但是，在

op:join-inner

期间，尽管来自

$people

和

$questions

的 op:result 中具有相同的条目，但返回的结果为空。下面可以看到一段返回的结果。

结果返回

词典.people

{"lexicon.people":"/people/Aaren_DETERS/000000000055933"}
{"lexicon.people":"/people/Aaren_HOWK/000000000117433"}
{"lexicon.people":"/people/Aaren_HUSTEDT/000000000038649"}
{"lexicon.people":"/people/Aaren_SHUSTA/000000000123065"}
{"lexicon.people":"/people/Aaren_SIEBERS/000000000035010"}
{"lexicon.people":"/people/Aarika_BETHARD/000000000048955"}
{"lexicon.people":"/people/Aarika_CHO/000000000093078"}
{"lexicon.people":"/people/Aarika_EVORA/000000000117911"}
{"lexicon.people":"/people/Aarika_LUCKRITZ/000000000001593"}
{"lexicon.people":"/people/Aarika_MCALPHIN/000000000043365"}
{"lexicon.people":"/people/Aarika_PAET/000000000067579"}
{"lexicon.people":"/people/Aarika_SENGUN/000000000047752"}
{"lexicon.people":"/people/Aarika_WEDEMEYER/000000000022594"}
......

sparql.person

......
{"sparql.person":"/people/Aaren_CRIBLEZ/000000000087536", "sparql.dob":"1999-07-21T00:19:21"}
{"sparql.person":"/people/Aaren_DEBRITO/000000000049208", "sparql.dob":"2018-10-09T08:09:48"}
{"sparql.person":"/people/Aaren_DEMASTERS/000000000091082", "sparql.dob":"2014-08-21T06:43:44"}
{"sparql.person":"/people/Aaren_DETERS/000000000055933", "sparql.dob":"2011-09-11T02:44:22"}
{"sparql.person":"/people/Aaren_GARY/000000000100658", "sparql.dob":"1998-06-04T00:39:23"}
{"sparql.person":"/people/Aaren_HANNAWAY/000000000045087", "sparql.dob":"2002-06-17T05:45:15"}
{"sparql.person":"/people/Aaren_HOWK/000000000117433", "sparql.dob":"2002-06-21T06:00:34"}
{"sparql.person":"/people/Aaren_HUSTEDT/000000000038649", "sparql.dob":"2018-06-07T14:56:39"}
{"sparql.person":"/people/Aaren_JURICH/000000000039301", "sparql.dob":"2003-07-14T16:20:05"}
{"sparql.person":"/people/Aaren_KRACK/000000000101407", "sparql.dob":"2014-03-19T06:25:39"}
{"sparql.person":"/people/Aaren_MACCONNELL/000000000053205", "sparql.dob":"1995-06-21T16:15:53"}
.....

我还做了一些额外的测试，其中以下代码用于使用

op:from-sparql

生成部分结果

let $query = 'SELECT * WHERE {?person </has_age> ? age . 
                              FILTER(?age > 75)}'
let $questions2 := op:from-sparql($query, "sparql2")

使用这个结果我执行了

op:join-inner

并且效果非常好。这让我想到

op:from-lexicons

可能会返回与

op:from-sparql

不兼容的某种数据格式？任何澄清或建议将不胜感激。

==更新==

用于投射的查询

let $questions := op:from-sparql('SELECT * WHERE {?person </has_dob> ?dob. }', "sparql")
                => op:select((  "person", op:as('person_string',fn:string(op:col('person'))) ))

==更新2==

import module namespace op="http://marklogic.com/optic" at "/MarkLogic/optic.xqy";
let $people := op:from-lexicons(
  map:entry("people",cts:uri-reference()),
  "lexicon"
)=>op:where(
     cts:path-geospatial-query("people_data/location",
    cts:circle(7500, cts:point(89.39101918779838, 51.97989163203445)),
    "type=long-lat-point")
  )

let $questions := op:from-sparql('SELECT * WHERE {?person </has_dob> ?dob. }', "sparql") 
                => op:select(( "dob", op:as('personStr',ofn:string(op:col('person'))) ))

return $questions  => op:join-inner(
    $people,
    op:on(
      "people","personStr"
    )
  ) => op:select(("personStr","dob")) => op:count("Row Count", "personStr") => op:result()

Answer 1

我相信 URI 词典的类型为 xs:string，三重主题通常类型为 sem:iri。

一种检查方法是在 SPARQL 行上使用 op:select() 和 oxs:string() 光学表达式，在内部联接之前将主题值转换为字符串。

如果可行，那么使用 TDE 模板创建具有 xs:string 数据类型而不是 sem:iri 数据类型的主题可能会更有利。

希望有帮助，