ES 查询数字

What is Elasticsearch?

You know, for search (and analysis)

Elasticsearch is the distributed search and analytics engine at the heart of the Elastic Stack.

Elasticsearch provides near real-time search and analytics for all types of data.

从官网介绍可以看出几个关键的字眼，Elasticsearch是分布式的搜索、存储和数据分析引擎。Elasticsearch为所有类型的数据提供近乎实时的搜索和分析。

它很强很好用。后面我会总结一些Elasticsearch的相关文章，本文只体验体验它的搜索功能。

准备工作

安装、启动Elasticsearch，kibana

版本：7.9

下载Elasticsearch和kibana，解压之后进入各自文件夹下的bin目录下，双击.bat文件启动即可，此处略过。

本文主要目的是看elasticsearch的查询功能有多爽，原理性问题后面再说。

验证Elasticsearch启动

Elasticsearch启动成功

Kibana启动成功：

Kibana启动成功

另外，建议安装一个elasticsearch-head，它能帮助我们很直观的查看ES节点状态。

elasticsearch-head提供可视化的操作页面，对ElasticSearch搜索引擎进行各种设置和数据检索功能。

通过它可以很直观的查看集群的健康状况，索引分配情况，还可以管理索引和集群以及提供方便快捷的搜索功能等等。

安装、启动elasticsearch-head：

1. 安装node，略
2. 解压glasticsearch-head-master，并进入该文件夹，修改Gruntfile.js，在connect.server.options添加hostname: '*'：
connect: {
 server: {
  options: {
   hostname: '*',
   port: 9100,
   base: '.',
   keepalive: true
  }
 }
}
3. npm安装：D:\Java\elasticsearch-head-master> npm install
4. 启动：D:\Java\elasticsearch-head-master> npm run start

D:\Java\elasticsearch-head-master> npm run start                                                
> elasticsearch-head@0.0.0 start D:\Java\elasticsearch-head-master
> grunt server

Running "connect:server" (connect) task
Waiting forever...
Started connect web server on http://localhost:9100

1. 安装node，略
2. 解压glasticsearch-head-master，并进入该文件夹，修改Gruntfile.js，在connect.server.options添加hostname: '*'：
connect: {
 server: {
  options: {
   hostname: '*',
   port: 9100,
   base: '.',
   keepalive: true
  }
 }
}
3. npm安装：D:\Java\elasticsearch-head-master> npm install
4. 启动：D:\Java\elasticsearch-head-master> npm run start

D:\Java\elasticsearch-head-master> npm run start                                                
> elasticsearch-head@0.0.0 start D:\Java\elasticsearch-head-master
> grunt server

Running "connect:server" (connect) task
Waiting forever...
Started connect web server on http://localhost:9100

ES创建索引

启动Kibana后，直接在Kibana Dev Tools控制台执行。

1. 建立索引

# 建立city索引
PUT /city

# 创建的每个索引都可以具有与之关联的特定设置，这些设置在主体中定义
# number_of_shards的默认值为1
# number_of_replicas的默认值为1(即每个主分片一个副本)
PUT /test
{
  "settings": {
    "index": {
      "number_of_shards": 3,
      "number_of_replicas": 2
    }
  }
}

# 建立city索引
PUT /city

# 创建的每个索引都可以具有与之关联的特定设置，这些设置在主体中定义
# number_of_shards的默认值为1
# number_of_replicas的默认值为1(即每个主分片一个副本)
PUT /test
{
  "settings": {
    "index": {
      "number_of_shards": 3,
      "number_of_replicas": 2
    }
  }
}

我们可以看到，建立的city索引，有1个分片，1个副本，这也是默认值；而test索引，通过settings配置了分片数为3，副本数为2。由图中也可以看出test有3个分片，每个分片有2个副本。

为什么副本都是unassigned的呢？这是因为ES不允许Primary和它的Replica放在同一个节点中，并且同一个节点不接受完全相同的两个Replica，而我本地只启动了一个ES节点。

2. 删除索引

上图中，test和city中间有一个ilm-history-2-000001，我也不知道它是啥，要不把它删掉吧？

# 删除索引
DELETE /ilm-history-2-000001

# 执行结果
{
  "acknowledged" : true
}

# 删除索引
DELETE /ilm-history-2-000001

# 执行结果
{
  "acknowledged" : true
}

可以通过查询索引验证一下：

# 查询索引
GET /ilm-history-2-000001

{
  "error" : {
    "root_cause" : [
      {
        "type" : "index_not_found_exception",
        "reason" : "no such index [ilm-history-2-000001]",
        "resource.type" : "index_or_alias",
        "resource.id" : "ilm-history-2-000001",
        "index_uuid" : "_na_",
        "index" : "ilm-history-2-000001"
      }
    ],
    "type" : "index_not_found_exception",
    "reason" : "no such index [ilm-history-2-000001]",
    "resource.type" : "index_or_alias",
    "resource.id" : "ilm-history-2-000001",
    "index_uuid" : "_na_",
    "index" : "ilm-history-2-000001"
  },
  "status" : 404
}

# 查询索引
GET /ilm-history-2-000001

{
  "error" : {
    "root_cause" : [
      {
        "type" : "index_not_found_exception",
        "reason" : "no such index [ilm-history-2-000001]",
        "resource.type" : "index_or_alias",
        "resource.id" : "ilm-history-2-000001",
        "index_uuid" : "_na_",
        "index" : "ilm-history-2-000001"
      }
    ],
    "type" : "index_not_found_exception",
    "reason" : "no such index [ilm-history-2-000001]",
    "resource.type" : "index_or_alias",
    "resource.id" : "ilm-history-2-000001",
    "index_uuid" : "_na_",
    "index" : "ilm-history-2-000001"
  },
  "status" : 404
}

也可以通过elasticsearch-head查看：

删除索引验证

没有ilm-history-2-000001索引了。

3. 插入数据

这个语法很简单，可参考如下：

POST /city/_doc/1
{
    "city" : "En shi",
    "province" :  "Hubei province",
    "acreage" :  24111
}

POST /city/_doc/2
{
    "city" : "E zhou",
    "province" :  "Hu bei province",
    "acreage" :  1594
}

POST /city/_doc/3
{
    "city" : "Zheng zhou, China",
    "province" :  "Henan province, capital",
    "acreage" :  7446
}

POST /city/_doc/4
{
    "city" : "Bei jing",
    "province" :  "Beijing China, capital",
    "acreage" :  16410
}

POST /city/_doc/5
{
    "city" : "Nan jing",
    "province" :  "Jiangsu province, capital",
    "acreage" :  6587
}

POST /city/_doc/6
{
    "city" : "Shen zhen",
    "province" :  "Guangdong province",
    "acreage" :  1997
}

POST /city/_doc/7
{
    "city" : "Guang zhou",
    "province" :  "Guangdong province, capital",
    "acreage" :  7434
}

POST /city/_doc/1
{
    "city" : "En shi",
    "province" :  "Hubei province",
    "acreage" :  24111
}

POST /city/_doc/2
{
    "city" : "E zhou",
    "province" :  "Hu bei province",
    "acreage" :  1594
}

POST /city/_doc/3
{
    "city" : "Zheng zhou, China",
    "province" :  "Henan province, capital",
    "acreage" :  7446
}

POST /city/_doc/4
{
    "city" : "Bei jing",
    "province" :  "Beijing China, capital",
    "acreage" :  16410
}

POST /city/_doc/5
{
    "city" : "Nan jing",
    "province" :  "Jiangsu province, capital",
    "acreage" :  6587
}

POST /city/_doc/6
{
    "city" : "Shen zhen",
    "province" :  "Guangdong province",
    "acreage" :  1997
}

POST /city/_doc/7
{
    "city" : "Guang zhou",
    "province" :  "Guangdong province, capital",
    "acreage" :  7434
}

以上面的数据为基础，开始ES常用查询。

ES查询

Elasticsearch查询有很多，下面针对常用查询做一个总结。

Query_string

1. 查询所有

GET /索引/_search

GET /city/_search

GET /city/_search

查询所有结果

查询出所有的7条记录，并且relation类型为eq(equal)，max_score为1.0(相关度分数)

2. 带参数的查询

GET /索引/_search?q=xx:xx

GET /city/_search?q=city: Bei Jing

"hits" : {
    "total" : {
      "value" : 2,
      "relation" : "eq"
    },
    "max_score" : 2.8371272,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "4",
        "_score" : 2.8371272,
        "_source" : {
          "city" : "Bei jing",
          "province" : "Beijing China, capital",
          "acreage" : 16410
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "5",
        "_score" : 1.1631508,
        "_source" : {
          "city" : "Nan jing",
          "province" : "Jiangsu province, capital",
          "acreage" : 6587
        }
      }
    ]
  }

GET /city/_search?q=city: Bei Jing

"hits" : {
    "total" : {
      "value" : 2,
      "relation" : "eq"
    },
    "max_score" : 2.8371272,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "4",
        "_score" : 2.8371272,
        "_source" : {
          "city" : "Bei jing",
          "province" : "Beijing China, capital",
          "acreage" : 16410
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "5",
        "_score" : 1.1631508,
        "_source" : {
          "city" : "Nan jing",
          "province" : "Jiangsu province, capital",
          "acreage" : 6587
        }
      }
    ]
  }

这个查询把city中带jing的都查出来了，但相关度分数不一样。

3. 分页，排序查询

GET /索引/_search?from=x&size=x&sort=xx:[asc|desc]

GET /city/_search?from=0&size=3&sort=acreage:asc

"hits" : {
    "total" : {
      "value" : 7,
      "relation" : "eq"
    },
    "max_score" : null,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "2",
        "_score" : null,
        "_source" : {
          "city" : "E zhou",
          "province" : "Hu bei province",
          "acreage" : 1594
        },
        "sort" : [
          1594
        ]
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "6",
        "_score" : null,
        "_source" : {
          "city" : "Shen zhen",
          "province" : "Guangdong province",
          "acreage" : 1997
        },
        "sort" : [
          1997
        ]
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "5",
        "_score" : null,
        "_source" : {
          "city" : "Nan jing",
          "province" : "Jiangsu province, capital",
          "acreage" : 6587
        },
        "sort" : [
          6587
        ]
      }
    ]
  }

GET /city/_search?from=0&size=3&sort=acreage:asc

"hits" : {
    "total" : {
      "value" : 7,
      "relation" : "eq"
    },
    "max_score" : null,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "2",
        "_score" : null,
        "_source" : {
          "city" : "E zhou",
          "province" : "Hu bei province",
          "acreage" : 1594
        },
        "sort" : [
          1594
        ]
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "6",
        "_score" : null,
        "_source" : {
          "city" : "Shen zhen",
          "province" : "Guangdong province",
          "acreage" : 1997
        },
        "sort" : [
          1997
        ]
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "5",
        "_score" : null,
        "_source" : {
          "city" : "Nan jing",
          "province" : "Jiangsu province, capital",
          "acreage" : 6587
        },
        "sort" : [
          6587
        ]
      }
    ]
  }

查出来按面积acreage排序的前3条记录，总记录是7。还可以看出，相关度分数为null。

Query DSL

1. match_all：匹配所有

GET /city/_search
{
  "query": {
    "match_all": {}
  }
}

GET /city/_search
{
  "query": {
    "match_all": {}
  }
}

和GET /city/_search不带{}查询结果一致。2. match：xx字段包含xx

查询city字段中带zhou的：

GET /city/_search
{
  "query": {
    "match": {
      "city": "zhou"
    }
  }
}

# 结果截取
"hits" : {
    "total" : {
      "value" : 3,
      "relation" : "eq"
    },
    "max_score" : 0.8266786,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "2",
        "_score" : 0.8266786,
        "_source" : {
          "city" : "E zhou",
          "province" : "Hu bei province",
          "acreage" : 1594
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "3",
        "_score" : 0.8266786,
        "_source" : {
          "city" : "Zheng zhou",
          "province" : "Henan province, capital",
          "acreage" : 7446
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "7",
        "_score" : 0.8266786,
        "_source" : {
          "city" : "Guang zhou",
          "province" : "Guangdong province, capital",
          "acreage" : 7434
        }
      }
    ]
  }

GET /city/_search
{
  "query": {
    "match": {
      "city": "zhou"
    }
  }
}

# 结果截取
"hits" : {
    "total" : {
      "value" : 3,
      "relation" : "eq"
    },
    "max_score" : 0.8266786,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "2",
        "_score" : 0.8266786,
        "_source" : {
          "city" : "E zhou",
          "province" : "Hu bei province",
          "acreage" : 1594
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "3",
        "_score" : 0.8266786,
        "_source" : {
          "city" : "Zheng zhou",
          "province" : "Henan province, capital",
          "acreage" : 7446
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "7",
        "_score" : 0.8266786,
        "_source" : {
          "city" : "Guang zhou",
          "province" : "Guangdong province, capital",
          "acreage" : 7434
        }
      }
    ]
  }

查出来3条结果，都有相关度分数。

3. sort：排序，正序，倒序

查询province中包含capital的并且按照面积倒序排序：

GET /city/_search
{
  "query": {
    "match": {
      "province": "capital"
    }
  },
  "sort": [
    {
      "acreage": {
        "order": "desc"
      }
    }
  ]
}

GET /city/_search
{
  "query": {
    "match": {
      "province": "capital"
    }
  },
  "sort": [
    {
      "acreage": {
        "order": "desc"
      }
    }
  ]
}

sort查询结果

4. multi_match：根据多个字段查询一个关键词

查询city和province字段中包含China的：

GET /city/_search
{
  "query": {
    "multi_match": {
      "query": "China",
      "fields": ["city", "province"]
    }
  }
}

GET /city/_search
{
  "query": {
    "multi_match": {
      "query": "China",
      "fields": ["city", "province"]
    }
  }
}

multi_match查询结果

5. _source 元数据：可以指定显示的字段

设置查询结果只显示acreage字段：

GET /city/_search
{
  "query": {
    "multi_match": {
      "query": "China",
      "fields": ["city", "province"]
    }
  },
  "_source": ["acreage"]
}

GET /city/_search
{
  "query": {
    "multi_match": {
      "query": "China",
      "fields": ["city", "province"]
    }
  },
  "_source": ["acreage"]
}

_source查询指定的字段

只显示了acreage字段。

6. 分页(deep-paging)

按照acreage倒序排序，并分页，每页3条记录，查询第一页：

GET /city/_search
{
  "query": {
    "match_all": {}
  },
  "sort": [
    {
      "acreage": {
        "order": "desc"
      }
    }
  ],
  "from": 0,
  "size": 3
}

GET /city/_search
{
  "query": {
    "match_all": {}
  },
  "sort": [
    {
      "acreage": {
        "order": "desc"
      }
    }
  ],
  "from": 0,
  "size": 3
}

全文检索 Full-text queries

1. query-term & query-match

GET /city/_search
{
  "query": {
    "term": {
      "city": {
        "value": "Guang zhou"
      }
    }
  }
}

GET /city/_search
{
  "query": {
    "match": {
      "city": "Guang zhou"
    }
  }
}

GET /city/_search
{
  "query": {
    "term": {
      "city": {
        "value": "Guang zhou"
      }
    }
  }
}

GET /city/_search
{
  "query": {
    "match": {
      "city": "Guang zhou"
    }
  }
}

query-term查询结果：

query-term查询结果

没有任何记录！！！再来看一下query-match查询结果：

query-match查询结果

有3条记录！！！

2. match和term区别

为什么会出现1那样的结果呢？

因为query-term查询的term不会分词，会将Guang zhou当做一个整体进行操作，而match会进行分词，分成Guang和zhou，所以查询结果里面city包含zhou的都出来了！

3. 全文检索

我们来看下面这个查询：

GET /city/_search
{
  "query": {
    "match": {
      "province": "Guangdong province, capital"
    }
  }
}

GET /city/_search
{
  "query": {
    "match": {
      "province": "Guangdong province, capital"
    }
  }
}

全文检索结果

查出来7条记录，每条记录都有相关度分数，并且按照相关度分数由高到低排好序了！

验证一下分词：

GET /_analyze
{
  "analyzer": "standard",
  "text": "Guangdong province, capital"
}

GET /_analyze
{
  "analyzer": "standard",
  "text": "Guangdong province, capital"
}

结果：

{
  "tokens" : [
    {
      "token" : "guangdong",
      "start_offset" : 0,
      "end_offset" : 9,
      "type" : "",
      "position" : 0
    },
    {
      "token" : "province",
      "start_offset" : 10,
      "end_offset" : 18,
      "type" : "",
      "position" : 1
    },
    {
      "token" : "capital",
      "start_offset" : 20,
      "end_offset" : 27,
      "type" : "",
      "position" : 2
    }
  ]
}

{
  "tokens" : [
    {
      "token" : "guangdong",
      "start_offset" : 0,
      "end_offset" : 9,
      "type" : "",
      "position" : 0
    },
    {
      "token" : "province",
      "start_offset" : 10,
      "end_offset" : 18,
      "type" : "",
      "position" : 1
    },
    {
      "token" : "capital",
      "start_offset" : 20,
      "end_offset" : 27,
      "type" : "",
      "position" : 2
    }
  ]
}

由此可见，Guangdong province, capital被分成了guangdong，province，capital，ES会全文检索这些词，所以查出了所有包含guangdong，province，capital的document。

Phrase search 短语搜索

GET /city/_search
{
  "query": {
    "match_phrase": {
      "province": "Guangdong province, capital"
    }
  }
}

GET /city/_search
{
  "query": {
    "match_phrase": {
      "province": "Guangdong province, capital"
    }
  }
}

和全文检索相反，“GuangdongGuangdong province, capital”会作为一个短语去检索，应该会只查出一条记录：

短语搜索结果

看图，结果确实如此。

Query and filter 查询和过滤

bool

可以组合多个查询条件，bool查询也是采用more_matches_is_better的机制，因此满足must和should子句的文档(可理解为数据行)将会合并起来计算分值(相关度)。

• must 必须满足

子句(查询)必须出现在匹配的文档中，并将有助于得分。

• filte 过滤器 不计算相关度分数，cache

子句(查询)必须出现在匹配的文档中。但是不像must，查询的相关度分数将被忽略。

Filter子句在filter上下文中执行，这意味着相关度得分被忽略，并且子句被考虑用于缓存。查询性能很高。

• should 可能满足(SQL中的or)

子句(查询)应出现在匹配的文档中。也可以不在文档中。

• must_not：必须不满足 不计算相关度分数

子句(查询)不得出现在匹配的文档中。子句在过滤器上下文中执行，这意味着相关度得分被忽略，并且子句被视为用于缓存。由于忽略得分，得分将会返回数字0。

• minimum_should_match

案例

在city这个index增加几条记录：

POST /city/_doc/8
{
    "city" : "Fo shan",
    "province" :  "Guangdong province",
    "acreage" :  3797
}
POST /city/_doc/9
{
    "city" : "Dong guan",
    "province" :  "Guangdong province",
    "acreage" :  2460
}
POST /city/_doc/10
{
    "city" : "Hui zhou",
    "province" :  "Guangdong province",
    "acreage" :  11347
}
POST /city/_doc/11
{
    "city" : "Mei zhou",
    "province" :  "Guangdong province",
    "acreage" :  15864
}

POST /city/_doc/8
{
    "city" : "Fo shan",
    "province" :  "Guangdong province",
    "acreage" :  3797
}
POST /city/_doc/9
{
    "city" : "Dong guan",
    "province" :  "Guangdong province",
    "acreage" :  2460
}
POST /city/_doc/10
{
    "city" : "Hui zhou",
    "province" :  "Guangdong province",
    "acreage" :  11347
}
POST /city/_doc/11
{
    "city" : "Mei zhou",
    "province" :  "Guangdong province",
    "acreage" :  15864
}

• 查询province包含Guangdong province，面积大于10000，并且city字段包含hui的document：

GET /city/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "city": "hui"
          }
        }
      ],
      "filter": [
        {
          "match_phrase": {
            "province": "Guangdong province"
          }
        },
        {
          "range": {
            "acreage": {
              "gt": 10000
            }
          }
        }
      ]
    }
  }
}

GET /city/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "city": "hui"
          }
        }
      ],
      "filter": [
        {
          "match_phrase": {
            "province": "Guangdong province"
          }
        },
        {
          "range": {
            "acreage": {
              "gt": 10000
            }
          }
        }
      ]
    }
  }
}

这个执行过程是：

1. 先对province中包含Guangdong province并且面积大于10000的进行筛选，符合条件的有2条记录：

过滤1

2. 再对city中包含hui的进行过滤，最终结果为：

• bool多条件

查询city包含zhou不包含hui，province里包不包含guangdong都可以，面积要小于6000：

GET /city/_search
{
  "query": {
    "bool": {
      "must": [
        {"match": {
          "city": "zhou"
        }}
      ],
      "must_not": [
        {"match": {
          "city": "hui"
        }}
      ],
      "should": [
        {"match": {
          "province": "guangdong"
        }}
      ],
      "filter": [
        {"range": {
          "acreage": {
            "lte": 6000
          }
        }}
      ]
    }
  }
}

GET /city/_search
{
  "query": {
    "bool": {
      "must": [
        {"match": {
          "city": "zhou"
        }}
      ],
      "must_not": [
        {"match": {
          "city": "hui"
        }}
      ],
      "should": [
        {"match": {
          "province": "guangdong"
        }}
      ],
      "filter": [
        {"range": {
          "acreage": {
            "lte": 6000
          }
        }}
      ]
    }
  }
}

bool多条件查询结果

• 嵌套查询

minimum_should_match：参数指定should返回的文档必须匹配的子句的数量或百分比。

如果bool查询包含至少一个should子句，而没有must或 filter子句，则默认值为1。否则，默认值为0。

例如：

GET /city/_search
{
  "query": {
    "bool": {
      "must": [
        {"match": {
          "city": "zhou"
        }}
      ],
      "should": [
        {"range": {
          "acreage": {
            "gt": 1500
          }
        }},
        {
          "range": {
            "acreage": {
              "gt": 5000
            }
          }
        }
      ],
      "minimum_should_match": 1
    }
  }
}

GET /city/_search
{
  "query": {
    "bool": {
      "must": [
        {"match": {
          "city": "zhou"
        }}
      ],
      "should": [
        {"range": {
          "acreage": {
            "gt": 1500
          }
        }},
        {
          "range": {
            "acreage": {
              "gt": 5000
            }
          }
        }
      ],
      "minimum_should_match": 1
    }
  }
}

minimum_should_match的意思是在should的子句中必须至少满足一个条件。

本例查询结果为：

"hits" : {
    "total" : {
      "value" : 5,
      "relation" : "eq"
    },
    "max_score" : 2.7046783,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "7",
        "_score" : 2.7046783,
        "_source" : {
          "city" : "Guang zhou",
          "province" : "Guangdong province, capital",
          "acreage" : 7434
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "10",
        "_score" : 2.7046783,
        "_source" : {
          "city" : "Hui zhou",
          "province" : "Guangdong province",
          "acreage" : 11347
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "11",
        "_score" : 2.7046783,
        "_source" : {
          "city" : "Mei zhou",
          "province" : "Guangdong province",
          "acreage" : 15864
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "3",
        "_score" : 2.5874128,
        "_source" : {
          "city" : "Zheng zhou, China",
          "province" : "Henan province, capital",
          "acreage" : 7446
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "2",
        "_score" : 1.7046783,
        "_source" : {
          "city" : "E zhou",
          "province" : "Hu bei province",
          "acreage" : 1594
        }
      }
    ]
  }

"hits" : {
    "total" : {
      "value" : 5,
      "relation" : "eq"
    },
    "max_score" : 2.7046783,
    "hits" : [
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "7",
        "_score" : 2.7046783,
        "_source" : {
          "city" : "Guang zhou",
          "province" : "Guangdong province, capital",
          "acreage" : 7434
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "10",
        "_score" : 2.7046783,
        "_source" : {
          "city" : "Hui zhou",
          "province" : "Guangdong province",
          "acreage" : 11347
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "11",
        "_score" : 2.7046783,
        "_source" : {
          "city" : "Mei zhou",
          "province" : "Guangdong province",
          "acreage" : 15864
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "3",
        "_score" : 2.5874128,
        "_source" : {
          "city" : "Zheng zhou, China",
          "province" : "Henan province, capital",
          "acreage" : 7446
        }
      },
      {
        "_index" : "city",
        "_type" : "1",
        "_id" : "2",
        "_score" : 1.7046783,
        "_source" : {
          "city" : "E zhou",
          "province" : "Hu bei province",
          "acreage" : 1594
        }
      }
    ]
  }

查询出来的地市满足acreage大于1500或大于5000。

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