elasticsearch 查询索引以及nested查询

最新推荐文章于 2024-07-01 16:51:49 发布

原创最新推荐文章于 2024-07-01 16:51:49 发布 · 1.3k 阅读

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文章标签：

#nested #elasticsearch #should #painless #keyword

本文深入探讨Elasticsearch的索引管理，包括数据添加、布尔查询、聚合分析及嵌套字段查询等高级功能。通过具体案例，讲解如何利用bool查询、must与should条件组合实现精准搜索，以及agg分组、nested和script_field查询的实践应用。

查询索引

query查询

上一篇已经创建索引 link.
现在先往索引里添加数据

PUT bank/_bulk
{"index":{"_id":"1"}}
{"account_number":1,"balance":39225,"firstname":"Amber","lastname":"杜克","age":32,"gender":"M","address":"880 Holmes Lane","employer":"Pyrami","email":"amberduke@pyrami.com","city":"Brogan","state":"IL","obj1":{"name":"blue"}}
{"index":{"_id":"6"}}
{"account_number":6,"balance":5686,"firstname":"Hattie","lastname":"伯纳德","age":36,"gender":"M","address":"671 Bristol Street","employer":"Netagy","email":"hattiebond@netagy.com","city":"Dante","state":"TN","obj1":{"name":"green"}}
{"index":{"_id":"13"}}
{"account_number":13,"balance":32838,"firstname":"Nanette","lastname":"巴特斯","age":28,"gender":"F","address":"789 Madison Street","employer":"Quility","email":"nanettebates@quility.com","city":"Nogal","state":"VA","obj1":{"name":"blue"}}
{"index":{"_id":"18"}}
{"account_number":18,"balance":4180,"firstname":"Dale","lastname":"奥达曼斯","age":33,"gender":"M","address":"467 Hutchinson Court","employer":"Boink","email":"daleadams@boink.com","city":"Orick","state":"MD"}

数据使用https://raw.githubusercontent.com/elastic/elasticsearch/master/docs/src/test/resources/accounts.json
我在索引中新加了"obj1" : {“type” : “nested”} 类型;

query查询

bool查询 must 必须匹配gender为M并且state为MD的数据

GET bank/_search
{"query": {"bool": {"must": [
  {"match": {
    "gender": "M"
  }},{"match": {
    "state": "MD"
  }} 
]}}}

如果我需要查询gender 为M 或者 gender为F的数据

GET bank/_search
{"query": {"bool": {"should": [
    {"match": {
      "gender": "F"
    }} ,{"match": {
      "gender": "M"
    }}
  ]}
  }
}

must 和should组合使用

GET bank/_search
{"query": {"bool": {"must": [
  {"match": {
    "gender": "M"
  }},{"bool": {"should": [
    {"match": {
      "gender": "F"
    }} ,{"match": {
      "gender": "M"
    }}
  ]}}
]}}}

agg分组

GET bank/_search
{"query": {"match_all": {}},"aggs": {
  "age_avg": {
    "avg": {
      "field": "age"
    }
  }
},"size": 0}

nested 查询

GET bank/_search
{"query": {"nested": {
    "path": "obj1",
    "query": {"bool": {"must": [
      {"exists": {"field" : "obj1" }}
    ]}}
  }} }

script_field 查询

GET bank/_search
{"query": {"bool": {"must": [
  {"match_all": {}}
]}},"script_fields": {
  "firstname_length": {
    "script": {"lang": "painless",
        "source": "doc['firstname'].length"}
  }
},"_source": "*"}

想要计算下firstname 的长度结果报错

"reason": "Fielddata is disabled on text fields by default. Set fielddata=true on [firstname] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory. Alternatively use a keyword field instead."

英文firstname 为text类型进行了分词我们换成keyword字段试一试

GET bank/_search
{"query": {"bool": {"must": [
  {"match_all": {}}
]}},"script_fields": {
  "email_length": {
    "script": {"lang": "painless",
        "source": "doc['email'].length"}
  }
},"_source": "*"}