es 字段截取聚合分组

GET /mybooks/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "prefix": {
            "region_id": "11"
          }
        }
      ]
    }
  },
  "aggs": {
    "group_location": {
      "terms": {
        "script": {
          "source": "boolean b = doc['region_id'].size() > 0;String c = doc['region_id'].value;if (b && c.length() > 2){return c.substring(0, 2)}"
        },
        "size": 6
      },
      "aggs": {
        "group_ent": {
          "terms": {
            "field": "_id",
            "size": 6,
            "order": {
              "nest>total": "desc"
            }
          },
          "aggs": {
            "nest": {
              "nested": {
                "path": "info"
              },
              "aggs": {
                "total": {
                  "sum": {
                    "field": "info.money"
                  }
                }
              }
            }
          }
        }
      }
    }
  },
  "from": 0,
  "size": 0
}