Elasticsearch，嵌套类型，如何获取存储桶

Question

使用与帖子here相同的示例。假设两个字段address.city和address.stateOrProvince都是嵌套类型，并且聚合不指定"nested":{"path":<nested path>}。聚合结果没有doc_count的总和。由于未指定"nested":{"path":<nested path>}，因此根级别命中的根级别doc_count不是存储桶中doc_count的总和。

[编辑]，将示例添加为Val的注释，activities是嵌套类型。 query1指定了"nested":{"path":<nested path>"}但查询2没有。在result2中，如何获取存储桶中所有项目的doc_count的总和，在这种情况下为2 + 1 + 1 + 1。

// DOC1

{
"activities.entry.time": "2015-09-15T17:49:35.687Z",
"activities.duration": "18747",
"activities.entry.time": "2015-09-15T17:49:54.639Z",
"activities.duration": "65",
"activities.entry.time": "2015-09-15T17:49:56.737Z",
"activities.duration": "449",
"activities.entry.time": "2015-09-15T17:49:56.772Z",
"activities.duration": "412"}

// DOC2

{
"activities.entry.time": "2015-09-15T17:55:43.304Z",
"activities.duration": "18675",
"activities.entry.time": "2015-09-15T17:56:02.150Z",
"activities.duration": "88",
"activities.entry.time": "2015-09-15T17:56:04.269Z",
"activities.duration": "396",
"activities.entry.time": "2015-09-15T17:56:04.314Z",
"activities.duration": "349"}

// doc3的

{
"activities.entry.time": "2015-09-15T17:49:56.087Z",
"activities.duration": "18723",
"activities.entry.time": "2015-09-15T17:50:15.002Z",
"activities.duration": "77",
"activities.entry.time": "2015-09-15T17:50:17.125Z",
"activities.duration": "418",
"activities.entry.time": "2015-09-15T17:50:17.137Z",
"activities.duration": "404"}

// QUERY1

{
"size": 0,
"aggs": {
    "dim0": {
        "nested": {
            "path": "activities"
        },
        "aggs": {
            "dh": {
                "date_histogram": {
                    "field": "activities.entry.time",
                    "interval": "minute",
                    "format": "yyyy-MM-dd",
                    "pre_zone": -7
                },
                "aggs": {
                    "avg_duration": {
                        "avg": {
                            "field": "activities.duration"
                        }
                    }
                }
            }
        }
    }
}}

// RESULT1

{
"took": 3,
"timed_out": false,
"_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
},
"hits": {
    "total": 3,
    "max_score": 0.0,
    "hits": []
},
"aggregations": {
    "dim0": {
        "doc_count": 12,
        "dh": {
            "buckets": [{
                "key_as_string": "2015-09-15",
                "key": 1442339340000,     //2015-09-15T17:49:00.000Z
                "doc_count": 5,           //4 count in doc1 + 1 count in doc3
                "avg_duration": {
                    "value": 7679.2       //(18747+65+449+412+18723) / 5
                }
            }, {
                "key_as_string": "2015-09-15",
                "key": 1442339400000,     //2015-09-15T17:50:00.000Z
                "doc_count": 3,
                "avg_duration": {
                    "value": 299.6666666666667
                }
            }, {
                "key_as_string": "2015-09-15",
                "key": 1442339700000,     //2015-09-15T17:55:00.000Z
                "doc_count": 1,
                "avg_duration": {
                    "value": 18675.0
                }
            }, {
                "key_as_string": "2015-09-15",
                "key": 1442339760000,     //2015-09-15T17:56:00.000Z
                "doc_count": 3,
                "avg_duration": {
                    "value": 277.6666666666667
                }
            }]
        }
    }
}}

// QUERY2

{
"size": 0,
"aggs": {
    "dh": {
        "date_histogram": {
            "field": "activities.entry.time",
            "interval": "minute",
            "format": "yyyy-MM-dd",
            "pre_zone": -7
        },
        "aggs": {
            "avg_duration": {
                "avg": {
                    "field": "activities.duration"
                }
            }
        }
    }
}}

// RESULT2

{
"took": 2,
"timed_out": false,
"_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
},
"hits": {
    "total": 3,
    "max_score": 0.0,
    "hits": []
},
"aggregations": {
    "dh": {
        "buckets": [{
            "key_as_string": "2015-09-15",
            "key": 1442339340000, //2015-09-15T17:49:00.000Z
            "doc_count": 2,       //doc1 + doc3
            "avg_duration": {
                "value": 4911.875 //(18747+65+449+412)+(18723+77+418+404)/8
            }
        }, {
            "key_as_string": "2015-09-15",
            "key": 1442339400000, //2015-09-15T17:50:00.000Z
            "doc_count": 1,
            "avg_duration": {
                "value": 4905.5
            }
        }, {
            "key_as_string": "2015-09-15",
            "key": 1442339700000, //2015-09-15T17:55:00.000Z
            "doc_count": 1,
            "avg_duration": {
                "value": 4877.0
            }
        }, {
            "key_as_string": "2015-09-15",
            "key": 1442339760000, //2015-09-15T17:56:00.000Z
            "doc_count": 1,
            "avg_duration": {
                "value": 4877.0
            }
        }]
    }
}}