Yoann Rodière ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *created* an issue Hibernate Search ( https://hibernate.atlassian.net/browse/HSEARCH?atlOrigin=eyJpIjoiOGRlOGY5... ) / Improvement ( https://hibernate.atlassian.net/browse/HSEARCH-3955?atlOrigin=eyJpIjoiOGR... ) HSEARCH-3955 ( https://hibernate.atlassian.net/browse/HSEARCH-3955?atlOrigin=eyJpIjoiOGR... ) Object fields that are both nested and flattened (ES's include_in_parent) ( https://hibernate.atlassian.net/browse/HSEARCH-3955?atlOrigin=eyJpIjoiOGR... ) Issue Type: Improvement Assignee: Unassigned Components: backend-elasticsearch, backend-lucene, engine Created: 18/Jun/2020 23:38 PM Fix Versions: 6.x-backlog Priority: Major Reporter: Yoann Rodière ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) While nested documents provide additional features, we don't needed nested documents for *everything*. Predicates on a single field when we're not using the nested predicate, in particular, work perfectly well on flattened object fields, and actually perform better since we don't need a runtime join. To get the best of both worlds, when one can spare the extra disk space it requires, we could allow object fields to be stored *both* as a nested document and flattened in their parent. Elasticsearch allows that with the attribute include_in_parent (see https://www.elastic.co/guide/en/elasticsearch/reference/current/nested.ht... ). API-wise, this could just be an additional value for the ObjectStructure enum: ObjectStructure.NESTED_AND_FLATTENED. We could then take advantage of this internally: when nesting is not necessary (no nested predicate, no filter in sorts and aggregations), we can just use the flattened field. ( https://hibernate.atlassian.net/browse/HSEARCH-3955#add-comment?atlOrigin... ) Add Comment ( https://hibernate.atlassian.net/browse/HSEARCH-3955#add-comment?atlOrigin... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100130- sha1:5f5b10c )