es - elasticsearch - aggs -bucket - date

世界上并没有完美的程序，但是我们并不因此而沮丧，因为写程序就是一个不断追求完美的过程。

问：date_range有什么特点？
答：

问：date_range如何使用？
答：

# 删除
DELETe /date_range_test

# 映射
PUT /date_range_test
{
  "mappings": {
    "properties": {
      "date": {"type": "date"}
    }
  }
}

# 索引
POST /date_range_test/_bulk?routing=1&refresh
{"index": {"_id": 1}}
{"date": "2021-09-29"}
{"index": {"_id": 2}}
{"date": "2021-09-28"}
{"index": {"_id": 3}}
{"date": "2021-09-27"}
{"index": {"_id": 4}}
{"date": "2021-09-30"}
{"index": {"_id": 5}}
{"date": null}


# 搜索 - missing要与format的格式一致
GET /date_range_test/_search
{
  "size": 0,
  "aggs": {
    "date_aggs": {
      "date_range": {
        "field": "date",
        "format": "yyyy-MM-dd",
        "keyed": true,
        "missing": "2021-09-30",
        "time_zone": "UTC",
        "ranges": [
          {
            "key": "r_1",
            "from": "2021-09-27",
            "to": "2021-09-28"
          },
          {
            "key": "r_2",
            "from": "2021-09-28",
            "to": "2021-09-30"
          },
          {
            "key": "r_3",
            "from": "2021-09-30",
            "to": "now/d"
          }
        ]
      }
    }
  }
}

# 结果
{
  "took" : 7,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 5,
      "relation" : "eq"
    },
    "max_score" : null,
    "hits" : [ ]
  },
  "aggregations" : {
    "date_aggs" : {
      "buckets" : {
        "r_1" : {
          "from" : 1.6327008E12,
          "from_as_string" : "2021-09-27",
          "to" : 1.6327872E12,
          "to_as_string" : "2021-09-28",
          "doc_count" : 1
        },
        "r_2" : {
          "from" : 1.6327872E12,
          "from_as_string" : "2021-09-28",
          "to" : 1.63296E12,
          "to_as_string" : "2021-09-30",
          "doc_count" : 2
        },
        "r_3" : {
          "from" : 1.63296E12,
          "from_as_string" : "2021-09-30",
          "to" : 1.6337376E12,
          "to_as_string" : "2021-10-09",
          "doc_count" : 2
        }
      }
    }
  }
}