How to Created Nested JSON objects in SOLR?

Question

I am dumping data in SOLR database. Earlier I was using Elastic Search and it was allowing me to store nested JSON objects.

Is there any way I can dynamically create nested JSON values when inserting in SOLR?

I am using JAVA as a backend language. My code is:

SolrInputDocument document = new SolrInputDocument();
document.addField("UUID", eventID);
document.addField("eventCategory", eventCategory);
.
.
.
.
document.addField("source", source);

I want something like this: 
{
"UUID":"1",
"source":abcd,
"eventCategory": {
    "event1":"a",
    "event2":"b",
    "event3":"c"
 }
}

user_2536745 · Answer

Solr is a collection of flat schema documents. You can add dynamic field to solr but it does not support nested JSON object.

But you can use nested documents specified in following resource.

https://lucene.apache.org/solr/guide/6_6/uploading-data-with-index-handlers.html

But querying on child documents is not as straightforward as ElasticSearch or MongoDB.

user_101762 · Answer

you can use addChildDocument to add the nested doc to the parent one. So code would be:

SolrInputDocument document = new SolrInputDocument();
document.addField("UUID", eventID);
document.addField("eventCategory", eventCategory);
...
SolrInputDocument child = new SolrInputDocument();
...
document.addChildDocument(child);

How to Created Nested JSON objects in SOLR?

2 Answers