Fielddata is disabled on text fields by default. Set fielddata=true on [title] in order to load...

聚合查询报错

Fielddata is disabled on text fields by default. Set fielddata=true on [title] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory. Alternatively use a keyword field instead.
解决方案：
https://www.elastic.co/guide/en/elasticsearch/reference/current/fielddata.html

PUT my_index/_mapping
{
  "properties": {
    "my_field": { 
      "type":     "text",
      "fielddata": true
    }
  }
}

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