Elasticsearch系统学习(四)-简单查询及聚合函数

一、ES简单查询

查询主要有如下几种:

1、query string search
2、query DSL
3、query filter
4、full-text search
5、phrase search
6、highlight search

1.1、query string search

适用于临时的在命令行使用一些工具,比如curl,快速的发出请求,来检索想要的信息;但是如果查询请求很复杂,是很难去构建的。在生产环境中,几乎很少使用query string search

搜索全部商品:GET /ecommerce/product/_search

GET /ecommerce/product/_search

{
  "took": 3,    #耗费了几毫秒
  "timed_out": false,   #是否超时,这里是没有
  "_shards": {    #数据拆成了5个分片,所以对于搜索请求,会打到所有的primary shard(或者是它的某个replica shard也可以)
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,   #查询结果的数量,4个document
    "max_score": 1,   #score的含义,就是document对于一个search的相关度的匹配分数,越相关,就越匹配,分数也高
    "hits": [    #包含了匹配搜索的document的详细数据
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1_update",
        "_score": 1,
        "_source": {
          "doc": {
            "name": "jiaqiangban gaolujie yaogao"
          }
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": 1,
        "_source": {
          "name": "jiajieshi yagao",
          "desc": "youxiao fangzhu",
          "price": 25,
          "producer": "jiajieshi producer",
          "tags": [
            "fangzhu"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": 1,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": 1,
        "_source": {
          "name": "zhonghua yagao",
          "desc": "caoben zhiwu",
          "price": 40,
          "producer": "zhonghua producer",
          "tags": [
            "qingxin"
          ]
        }
      }
    ]
  }
}

搜索商品名称中包含yagao的商品,而且按照售价降序序:GET /ecommerce/product/_searchq=name:yagao&sort=price:desc

GET /ecommerce/product/_search?q=name:yagao&sort=price:desc

{
  "took": 11,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 3,
    "max_score": null,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": null,
        "_source": {
          "name": "zhonghua yagao",
          "desc": "caoben zhiwu",
          "price": 40,
          "producer": "zhonghua producer",
          "tags": [
            "qingxin"
          ]
        },
        "sort": [
          40
        ]
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": null,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        },
        "sort": [
          30
        ]
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": null,
        "_source": {
          "name": "jiajieshi yagao",
          "desc": "youxiao fangzhu",
          "price": 25,
          "producer": "jiajieshi producer",
          "tags": [
            "fangzhu"
          ]
        },
        "sort": [
          25
        ]
      }
    ]
  }
}

1.2、query DSL

DSL:Domain Specified Language,特定领域的语言
http request body:请求体,可以用json的格式来构建查询语法,比较方便,可以构建各种复杂的语法,比query string search肯定强大多了

更加适合生产环境的使用,可以构建复杂的查询

1)查询所有的商品

GET /ecommerce/product/_search
{
  "query": {"match_all": {}}  #使用match_all
}

{
  "took": 4,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 3,
    "max_score": 1,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": 1,
        "_source": {
          "name": "jiajieshi yagao",
          "desc": "youxiao fangzhu",
          "price": 25,
          "producer": "jiajieshi producer",
          "tags": [
            "fangzhu"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": 1,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": 1,
        "_source": {
          "name": "zhonghua yagao",
          "desc": "caoben zhiwu",
          "price": 40,
          "producer": "zhonghua producer",
          "tags": [
            "qingxin"
          ]
        }
      }
    ]
  }
}

2)查询名称包含yagao的商品,同时按照价格降序排序

GET /ecommerce/product/_search
{
  "query": {
    "match": {
      "name": "yagao"
    }
  },
  "sort": [
    {"price": "desc"}  
  ]
}


{
  "took": 7,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 3,
    "max_score": null,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": null,
        "_source": {
          "name": "zhonghua yagao",
          "desc": "caoben zhiwu",
          "price": 40,
          "producer": "zhonghua producer",
          "tags": [
            "qingxin"
          ]
        },
        "sort": [
          40
        ]
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": null,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        },
        "sort": [
          30
        ]
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": null,
        "_source": {
          "name": "jiajieshi yagao",
          "desc": "youxiao fangzhu",
          "price": 25,
          "producer": "jiajieshi producer",
          "tags": [
            "fangzhu"
          ]
        },
        "sort": [
          25
        ]
      }
    ]
  }
}

3)分页查询商品

总共3条商品,假设每页就显示1条商品,现在显示第2页,所以就查出来第2个商品

GET /ecommerce/product/_search
{
  "query": {"match_all": {}},
  "from": 1,   #从第几个开始查询
  "size": 1    #查询几个
}

{
  "took": 2,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 3,
    "max_score": 1,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": 1,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        }
      }
    ]
  }
}

4)指定要查询出来商品的名称和价格

GET /ecommerce/product/_search
{
  "query": {"match_all": {}},
  "_source": ["name","price"]
}


{
  "took": 13,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 3,
    "max_score": 1,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": 1,
        "_source": {
          "price": 25,
          "name": "jiajieshi yagao"
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": 1,
        "_source": {
          "price": 30,
          "name": "gaolujie yagao"
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": 1,
        "_source": {
          "price": 40,
          "name": "zhonghua yagao"
        }
      }
    ]
  }
}

1.3、query filter

搜索商品名称包含yagao,而且售价大于25元的商品

GET /ecommerce/product/_search
{
  "query": {
    "bool": {
      "must": {
        "match": {
          "name":"yagao"
        }
      },
      "filter": {
        "range": {
        "price": {"gt": 25}
        }
      }
    }
  }
}


{
  "took": 7,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 2,
    "max_score": 0.25811607,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": 0.25811607,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": 0.25811607,
        "_source": {
          "name": "zhonghua yagao",
          "desc": "caoben zhiwu",
          "price": 40,
          "producer": "zhonghua producer",
          "tags": [
            "qingxin"
          ]
        }
      }
    ]
  }
}

1.4、full-text search(全文检索)

全文检索图解:

什么是全文检索

新增条数据:

put /ecommerce/product/4
{
  "name": "special yagao",
  "desc": "special meibai",
  "price": 50,
  "producer": "special yagao producer",
  "tags": ["meibai"]
}

查看所有数据:

GET /ecommerce/product/_search
{
  "query": {
    "match_all": {}
  }
}

全文检索:查询producer字段带有”yagao producer”的商品

GET /ecommerce/product/_search
{
  "query": {
    "match": {
      "producer": "yagao producer"
    }
  }
}

#原理说明:
producer这个字段,会先被拆解,建立倒排索引,yagao producer ---> yagao和producer

special		4
yagao		4
producer	1,2,3,4
gaolujie	1
zhognhua	3
jiajieshi	2


{
  "took": 14,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,
    "max_score": 0.70293105,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "4",
        "_score": 0.70293105,  #相关度得分最高
        "_source": {
          "name": "special yagao",
          "desc": "special meibai",
          "price": 50,
          "producer": "special yagao producer",
          "tags": [
            "meibai"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": 0.25811607,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": 0.25811607,
        "_source": {
          "name": "zhonghua yagao",
          "desc": "caoben zhiwu",
          "price": 40,
          "producer": "zhonghua producer",
          "tags": [
            "qingxin"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": 0.1805489,
        "_source": {
          "name": "jiajieshi yagao",
          "desc": "youxiao fangzhu",
          "price": 25,
          "producer": "jiajieshi producer",
          "tags": [
            "fangzhu"
          ]
        }
      }
    ]
  }
}

1.5、phrase search(短语搜索)

跟全文检索相对应,相反,全文检索会将输入的搜索串拆解开来,去倒排索引里面去一一匹配,只要能匹配上任意一个拆解后的单词,就可以作为结果返回
phrase search,要求输入的搜索串,必须在指定的字段文本中,完全包含一模一样的,才可以算匹配,才能作为结果返回

GET /ecommerce/product/_search
{
  "query": {
    "match_phrase": {
      "producer": "yagao producer"
    }
  }
}

{
  "took": 18,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0.70293105,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "4",
        "_score": 0.70293105,
        "_source": {
          "name": "special yagao",
          "desc": "special meibai",
          "price": 50,
          "producer": "special yagao producer",
          "tags": [
            "meibai"
          ]
        }
      }
    ]
  }
}

1.6、highlight search(高亮搜索结果)

image

GET /ecommerce/product/_search
{
  "query": {
    "match": {
      "producer":"producer"
    }
  },
  "highlight": {
    "fields": {
      "producer": {}
    }
  }
}


{
  "took": 37,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,
    "max_score": 0.25811607,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "1",
        "_score": 0.25811607,
        "_source": {
          "name": "gaolujie yagao",
          "desc": "gaoxiao meibai",
          "price": 30,
          "producer": "gaolujie producer",
          "tags": [
            "meibai",
            "fangzhu"
          ]
        },
        "highlight": {
          "producer": [
            "gaolujie <em>producer</em>"    #高亮显示<em>标签
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "3",
        "_score": 0.25811607,
        "_source": {
          "name": "zhonghua yagao",
          "desc": "caoben zhiwu",
          "price": 40,
          "producer": "zhonghua producer",
          "tags": [
            "qingxin"
          ]
        },
        "highlight": {
          "producer": [
            "zhonghua <em>producer</em>"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": 0.1805489,
        "_source": {
          "name": "jiajieshi yagao",
          "desc": "youxiao fangzhu",
          "price": 25,
          "producer": "jiajieshi producer",
          "tags": [
            "fangzhu"
          ]
        },
        "highlight": {
          "producer": [
            "jiajieshi <em>producer</em>"
          ]
        }
      },
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "4",
        "_score": 0.14638957,
        "_source": {
          "name": "special yagao",
          "desc": "special meibai",
          "price": 50,
          "producer": "special yagao producer",
          "tags": [
            "meibai"
          ]
        },
        "highlight": {
          "producer": [
            "special yagao <em>producer</em>"
          ]
        }
      }
    ]
  }
}

二、聚合函数

聚合函数有:avg,groupby,sort等

1)计算每个tag下的商品数量

GET /ecommerce/product/_search
{
  "aggs": {
    "group_by_tags": {   #通过标签进行分组,名称可以自己定义
      "terms": {
        "field": "tags"
      }
    }
  }
}

#报错
"Fielddata is disabled on text fields by default. Set fielddata=true on [tags] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory."

#解决方法:将文本field的fielddata属性设置为true
PUT /ecommerce/_mapping/product
{
  "properties": {
    "tags": {
      "type": "text",
      "fielddata": true
    }
  }
}

#再次查询
GET /ecommerce/product/_search
{
  "size": 0,   #不显示原始数据
  "aggs": {
    "all_tags": {
      "terms": { "field": "tags" }
    }
  }
}


{
  "took": 20,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "group_by_tags": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "fangzhu",
          "doc_count": 2
        },
        {
          "key": "meibai",
          "doc_count": 2
        },
        {
          "key": "qingxin",
          "doc_count": 1
        }
      ]
    }
  }
}

2)对名称中包含yagao的商品,计算每个tag下的商品数量

GET /ecommerce/product/_search
{
  "size": 0,
  "query": {
    "match": {
      "name": "yagao"
    }
  },
  "aggs": {
    "all_tags": {
      "terms": {
        "field": "tags"
      }
    }
  }
}

{
  "took": 2,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "all_tags": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "fangzhu",
          "doc_count": 2
        },
        {
          "key": "meibai",
          "doc_count": 2
        },
        {
          "key": "qingxin",
          "doc_count": 1
        }
      ]
    }
  }
}

3)先分组,再算每组的平均值,计算每个tag下的商品的平均价格

GET /ecommerce/product/_search
{
  "size": 0,
  "aggs": {
    "group_by_tags": {
      "terms": {
        "field": "tags"
      },
      "aggs": {
        "avg_price": {
          "avg": {
            "field": "price"
          }
        }
      }
    }
  }
}

{
  "took": 21,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "group_by_tags": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "fangzhu",
          "doc_count": 2,
          "avg_price": {
            "value": 27.5
          }
        },
        {
          "key": "meibai",
          "doc_count": 2,
          "avg_price": {
            "value": 40
          }
        },
        {
          "key": "qingxin",
          "doc_count": 1,
          "avg_price": {
            "value": 40
          }
        }
      ]
    }
  }
}

4)计算每个tag下的商品的平均价格,并且按照平均价格降序排序

GET /ecommerce/product/_search
{
  "size": 0,
  "aggs": {
    "all_tags": {
      "terms": {
        "field": "tags",
        "order": {
          "avg_price": "desc"
        }
      },
      "aggs": {
        "avg_price": {
          "avg": {
            "field": "price"
          }
        }
      }
    }
  }
}


{
  "took": 10,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "all_tags": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "meibai",
          "doc_count": 2,
          "avg_price": {
            "value": 40
          }
        },
        {
          "key": "qingxin",
          "doc_count": 1,
          "avg_price": {
            "value": 40
          }
        },
        {
          "key": "fangzhu",
          "doc_count": 2,
          "avg_price": {
            "value": 27.5
          }
        }
      ]
    }
  }
}

5)按照指定的价格范围区间进行分组,然后在每组内再按照tag进行分组,最后再计算每组的平均价格

GET /ecommerce/product/_search
{
  "size": 0,
  "aggs": {
    "group_by_price": {
      "range": {
        "field": "price",
        "ranges": [
          {
            "from": 0,
            "to": 20
          },
          {
            "from": 20,
            "to": 40
          },
          {
            "from": 40,
            "to": 50
          }
        ]
      },
      "aggs": {
        "group_by_tags": {
          "terms": {
            "field": "tags"
          },
          "aggs": {
            "avg_price": {
              "avg": {
                "field": "price"
              }
            }
          }
        }
      }
    }
  }
}


{
  "took": 22,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 4,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "group_by_price": {
      "buckets": [
        {
          "key": "0.0-20.0",
          "from": 0,
          "to": 20,
          "doc_count": 0,
          "group_by_tags": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": []
          }
        },
        {
          "key": "20.0-40.0",
          "from": 20,
          "to": 40,
          "doc_count": 2,
          "group_by_tags": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
              {
                "key": "fangzhu",
                "doc_count": 2,
                "avg_price": {
                  "value": 27.5
                }
              },
              {
                "key": "meibai",
                "doc_count": 1,
                "avg_price": {
                  "value": 30
                }
              }
            ]
          }
        },
        {
          "key": "40.0-50.0",
          "from": 40,
          "to": 50,
          "doc_count": 1,
          "group_by_tags": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
              {
                "key": "qingxin",
                "doc_count": 1,
                "avg_price": {
                  "value": 40
                }
              }
            ]
          }
        }
      ]
    }
  }
}
posted @ 2019-09-02 09:54  运维人在路上  阅读(1264)  评论(0编辑  收藏  举报