ES6 - 3简单数据查询

1. 查询单个文档
   格式：http://127.0.0.1:9200/people/man/1 [get]
   查到数据返回json
   未查到数据返回：

{
    "_index": "people",
    "_type": "man",
    "_id": "1",
    "found": false
}

2. 查询全部数据
   格式：http://127.0.0.1:9200/people/_search [post]
   请求内容：
   2.1 查全部（默认只返回10条）

{
    "query": {
        "match_all": {}
    }
}

2.2 查分页

{
    "query": {
        "match_all": {}
    },
    "from": 1,  // 从第几条查，第一条索引为0
    "size": 2, // 查几条
    "sort": [ // 排序规则
        {
            "date": {
                "order":"desc"
            }
        }
    ]
}

查询返回json格式：

{
    "took": 47,  // 查询消耗时间毫秒
    "timed_out": false,
    "_shards": {
        "total": 3,  
        "successful": 3,
        "skipped": 0,
        "failed": 0
    },
    "hits": { // 响应结果
        "total": 2, // 总数
        "max_score": 1,
        "hits": [ // 结果集
            {
                "_index": "people",
                "_type": "man",
                "_id": "36k2WWcBRM5zB9jDvej9",
                "_score": 1,
                "_source": {
                    "name": "张无忌",
                    "country": "China",
                    "age": 20,
                    "date": "1988-9-1"
                }
            },
            {
                "_index": "people",
                "_type": "man",
                "_id": "1",
                "_score": 1,
                "_source": {
                    "name": "张三丰",
                    "country": "China",
                    "age": 30,
                    "date": "1987-9-1"
                }
            }
        ]
    }
}

3. 按关键词查询
   格式：http://127.0.0.1:9200/people/_search [post]
   请求内容：

{
    "query": {
        "match": {
            "name": "张"
        }
    },
    "sort": [
        {
            "date": {
                "order":"desc"
            }
        }
    ]
}

4. 聚合查询
   请求内容：

{
    "aggs": {
        "group_by_xx": { // 结果节点，任意名称
            "terms": { // 分组
                "field": "date"
            }
        },
        "group_by_yy": {
            "terms": {
                "field": "country"
            }
        },
        "stats_1": {
            "stats": { // 统计数
                "field": "age"
            }
        },
        "stats_2": {
            "min": { // 指定某个具体统计类型（min、max、count、avg、sum）
                "field": "age"
            }
        }
    }
}

返回结果：

{
    "took": 79,
    "timed_out": false,
    "_shards": {
        "total": 3,
        "successful": 3,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": 2,
        "max_score": 1,
        "hits": [
            {
                "_index": "people",
                "_type": "man",
                "_id": "36k2WWcBRM5zB9jDvej9",
                "_score": 1,
                "_source": {
                    "name": "张无忌",
                    "country": "China",
                    "age": 20,
                    "date": "1988-9-1"
                }
            },
            {
                "_index": "people",
                "_type": "man",
                "_id": "1",
                "_score": 1,
                "_source": {
                    "name": "张三丰",
                    "country": "China",
                    "age": 30,
                    "date": "1987-9-1"
                }
            }
        ]
    },
    "aggregations": {
        "group_by_yy": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
                {
                    "key": "China",
                    "doc_count": 2
                }
            ]
        },
        "group_by_xx": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
                {
                    "key": 557452800000,
                    "key_as_string": "1987-09-01 00:00:00",
                    "doc_count": 1
                },
                {
                    "key": 589075200000,
                    "key_as_string": "1988-09-01 00:00:00",
                    "doc_count": 1
                }
            ]
        },
        "stats_1": {
            "count": 2,
            "min": 20,
            "max": 30,
            "avg": 25,
            "sum": 50
        },
        "stats_2": {
            "value": 20
        }
    }
}