Elasticsearch 面试题与答案

问题 61. Explain the use of the 'Nested' datatype in Elasticsearch.

The 'Nested' datatype in Elasticsearch is used when dealing with arrays of objects. It allows you to query and index objects as separate entities, maintaining the relationships.

Example:

PUT /my_index
{
  "mappings": {
    "properties": {
      "comments": {
        "type": "nested"
      }
    }
  }
}