Apache Solr中的多对一映射

Question

我正在使用Solr索引我的报告数据库.报告可以包含文本,提交者信息等.这当前有效,如下所示:

"docs": [
      {
        "Text": "Some Report Text"
        "ReportId": "1",
        "Date": "2013-08-09T14:59:28.147Z",
        "SubmitterId": "11111",
        "FirstName": "John",
        "LastName": "Doe",
        "_version_": 1444554112206110700
      }
 ]

报告可以拥有的另一件事是观众(这是一个报告和观众之间的一对多关系.)我希望能够在我的JSON输出中捕获这样的观众:

"docs": [
      {
        "Text": "Some Report Text"
        "ReportId": "1",
        "Date": "2013-08-09T14:59:28.147Z",
        "SubmitterId": "11111",
        "FirstName": "John",
        "LastName": "Doe",
        "Viewers": [
            { ViewerId: "22222" },
            { ViewerId: "33333" }
         ]
        "_version_": 1444554112206110700
      }
 ]

然而,我似乎无法实现这一点.这是我的data-config.xml(删除的部分不是问题所必需的):

<entity name="Report" query="select * from Reports">
   <field column="Text" />
   <field column="ReportId" />
   <!-- Get Submitter Information as another entity. -->
   <entity name="Viewers" query="select * from ReportViewers where Id='${Report.ReportId}'">
     <field column="Id" name="ViewerId" />
   </entity>
</entity>

而且schema.xml:

<field name="Text" type="text_en" indexed="true" stored="true" />
<field name="ReportId" type="string" indexed="true" stored="true" />
<field name="Viewers" type="string" indexed="true" stored="true" multiValued="true" />
<field name="ViewerId" type="string" indexed="true" stored="true" />

当我进行数据导入时,我什么都看不到.没有错误,没有任何明显的错误,但我很确定我的数据配置和/或我的架构不正确.我究竟做错了什么？

Answer 1

不幸的是,Solr不允许嵌套(参见http://lucene.472066.n3.nabble.com/Possible-to-have-Solr-documents-with-deeply-nested-data-structures-ie-hashes-within-hashes- td4004285.html).你需要压扁你的数据!

所以

"Viewers": [
            { ViewerId: "22222" },
            { ViewerId: "33333" }
         ]

不可能.而是扁平它并有一个ViewerIds数组:

"ViewerIds": ["22222", "33333" ]

在您的架构中,您将拥有:

<field name="ViewerIds" type="string" indexed="true" stored="true" multiValued="true" />

并相应地修改您的数据配置.