Question

I’ve got a question about the possibility to create nested fields in solr.
Google searches told me something about group but I think its just for the result?

what I want to have is a structure like that:

• Category1
  • item 1 (9)
  • item 2 (8)
• Category2
  • item 3 (6)
• Category3
  • item 4 (23)

I tried something like this:

<field name="Category" type="string" indexed="true" stored="true" multiValued="true" required="false">
<field name="MiscellaneousName" type="string" indexed="true" stored="true" multiValued="true" required="false"/>

But it does not work.

Update:
The categories and items should be faceted. Everey item(=facet) is part of a category. One Category could have multiple or null fields. The Categories and items are stored in a database an I want to index them dynamically. I only want to search for the items, the categories are just text. I’m using solr 3.3 with Tomcat 7.

Answer 1

Thanks for the update. Pivot facets allow you to do something like:

• Category1 (17)
  • item 1 (9)
  • item 2 (8)
• Category2 (6)
  • item 3 (6)
• Category3 (23)
  • item 4 (23)

.. but they are only available in Solr 4.0 (trunk). You can, however, simulate these results in lower Solr’s (down to 1.4), although it is a bit complicated and requires two Solr queries instead of one. I wrote a blog post on this — Pivot Faceting (Decision Trees) in Solr 1.4.

You can keep the schema you have in your original question — pivot faceting (real or simulated) works on any arbitrary, different (or same) fields.