Apache Solr Reference Guide Covering Apache Solr 6.0

Path
/update/csv
Default Parameters
stream.contentType=application/csv
The /update/csv path may be useful for clients sending in CSV formatted update commands from applications
where setting the Content-Type proves difficult.
For more information on the CSV Update Request Handler, see https://wiki.apache.org/solr/UpdateCSV.
Nested Child Documents
Solr indexes nested documents in blocks as a way to model documents containing other documents, such as a
blog post parent document and comments as child documents -- or products as parent documents and sizes,
colors, or other variations as child documents. At query time, the Block Join Query Parsers can search these
relationships. In terms of performance, indexing the relationships between documents may be more efficient than
attempting to do joins only at query time, since the relationships are already stored in the index and do not need
to be computed.
Nested documents may be indexed via either the XML or JSON data syntax (or using SolrJ) - but regardless of
syntax, you must include a field that identifies the parent document as a parent; it can be any field that suits this
purpose, and it will be used as input for the block join query parsers.
XML Examples
For example, here are two documents and their child documents:
1
Solr adds block join support
parentDocument
2
SolrCloud supports it too!
3
New Lucene and Solr release is out
parentDocument
4
Lots of new features
In this example, we have indexed the parent documents with the field content_type, which has the value
"parentDocument". We could have also used a boolean field, such as isParent, with a value of "true", or any
other similar approach.
JSON Examples
This example is equivalent to the XML example above, note the special _childDocuments_ key need to
indicate the nested documents in JSON.
Apache Solr Reference Guide 6.0
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