We need to store documents for our users. Each user will have a number of documents that all have the same core fields, we then allow users to add their own arbitrary fields to their documents. Reading this article: https://www.elastic.co/guide/en/elasticsearch/guide/current/mapping.html . It says "…

Storing documents with some arbitrary data

Apache, Apache Lucene, Apache Hadoop, Hadoop, HDFS and the yellow elephant logo are trademarks of the Apache Software Foundation in the United States and/or other countries.

Storing documents with some arbitrary data