Solr: Using the Block Join Children Query Parser

Question

Currently I evaluate the Block Join Children Query Parser as described here.

Therefore I have created the following collection:

curl "http://localhost:8983/solr/admin/collections?action=CREATE&name=nestedPerson&numShards=6"`

Then I have inserted these two documents:

curl http://localhost:8983/solr/nestedPerson/update?commitWithin=3000 -d '<add>
        <doc>
        <field name="id">p1</field>
        <field name="deceased">false</field>
        <doc>
            <field name="id">c1</field>
            <field name="firstName">Bob</field>
        </doc>
        </doc>
        <doc>
        <field name="id">p2</field>
        <field name="deceased">true</field>
        <doc>
            <field name="id">c2</field>
            <field name="firstName">Max</field>
        </doc>
        </doc>
    </add>'

Now I issue this query:

{!child of="id:p1"}firstName:Bob

Unfortunately this results in this error:

"msg": "Parent query yields document which is not matched by parents filter, docID=0",

How can the parent query (I guess that the part id:p1 is meant) yield a document that is not matched by the filter?

Answer 1

Take a look at the Solr Wiki that you refer to again here. Note the following:

The syntax for this parser is: q={!child of=<allParents>}<someParents>. The parameter allParents is a filter that matches only parent documents

In your example, the query is {!child of="id:p1"}firstName:Bob. The field id as used in<allParents>, but id is contained in both parent and child documents.

You need to introduce a field that only parent documents have, such as <field name="content_type">parentDocument</field> from the wiki. Once all parent documents (and only parent documents) have this field, you could submit the query as:

q={!parent which="content_type:parentDocument"}firstName:Bob

This would match child documents for firstName:Bob and return their parents. In a similar fashion, use q={!child of=<allParents>}<someParents> to match parent documents and return their children.