Fielddata

Fielddata is an on-disk data structure used by Elasticsearch to enable aggregations, sorting, and scripting on text fields. Because text fields are analyzed (broken down into individual terms), Elasticsearch needs a way to quickly access all the terms for a specific document when performing these operations. Fielddata loads all the terms for a field into memory, allowing for fast access during these operations.

Visit the following resources to learn more:

• @article@What is Elasticsearch Fielddata?
• @article@Elasticsearch Fielddata
• @video@Field Data vs Doc Values | Understanding Elasticsearch Performance Issues