Elasticsearch學習之ES的高級檢索

檢索概覽：
　　ES同MySQL一樣擁有衆多的查詢接口可以幫助用戶對指定的查詢內容進行匹配檢索查詢；如精確查詢、模糊查詢、前綴查詢、範圍查詢、正則表達式匹配查詢等。
　　查詢檢索子句分爲兩類：
　　　　1）查詢語句：執行全文本查詢時，基於相關度來評判其匹配結果；查詢執行過程複雜，且不會被緩存；
　　　　2）過濾語句：執行精確查詢時，基於其結果爲"yes"或"no"來進行評判；速度快，且結果可被緩存；

一、過濾語句
1）term filter：精確匹配包含指定term的文檔；
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d '{
  "query":{
     "term":{
        "age":"25"
      }
   }
}'

查詢結果：

{
  "took" : 4,     //查詢時長，毫秒;
  "timed_out" : false,     //是否超時;
  "_shards" : {      //分片情況;
    "total" : 5,     //總分片個數;
    "successful" : 5,    //成功分片的個數;
    "skipped" : 0,      //跳過的個數;
    "failed" : 0       //失敗的個數;
  },
  "hits" : {     //命中數據情況;
    "total" : 1,    //總命中數據個數;
    "max_score" : 1.0,    //打分情況;
    "hits" : [      //命中數據集;
      {
        "_index" : "student",     //索引名稱;
        "_type" : "class1",      //類型名稱;
        "_id" : "3",      //id情況;
        "_score" : 1.0,     //打分情況;
        "_source" : {      //源數據;
          "name" : "Yangguo",   //name字段與對應的值;
          "age" : 25,       //age字段與對應的值;
          "sex" : "M"      //sex字段與對應的值;
        }
      }
    ]
  }
}

2）terms filter：用於多值精確匹配
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d '{
  "query":{
     "terms":{
        "age":[25,30]
      }
   }
}'

查詢結果：

{
  "took" : 9,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 3,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "5",
        "_score" : 1.0,
        "_source" : {
          "name" : "Xiaofeng",
          "age" : 30,
          "sex" : "M"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "name" : "Guojing",
          "age" : 30,
          "sex" : "M"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "3",
        "_score" : 1.0,
        "_source" : {
          "name" : "Yangguo",
          "age" : 25,
          "sex" : "M"
        }
      }
    ]
  }
}

3）range filters:用於在指定的範圍內查找數值或時間
　　gt：大於
　　lt：小於
　　get：大於等於
　　let：小於等於
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty'  -d'{
    "query":{
       "range":{
          "age":{
             "gte":28,
             "lte":30
          }
       }
    }
}'

查詢結果：

{
  "took" : 2,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 4,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "5",
        "_score" : 1.0,
        "_source" : {
          "name" : "Xiaofeng",
          "age" : 30,
          "sex" : "M"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "name" : "Huangrong",
          "age" : 28,
          "sex" : "F"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "6",
        "_score" : 1.0,
        "_source" : {
          "name" : "Azhu",
          "age" : 28,
          "sex" : "F"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "name" : "Guojing",
          "age" : 30,
          "sex" : "M"
        }
      }
    ]
  }
}

4）exists and missing filters：字段存在與否檢索
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty'  -d'{
    "query":{
     "exists":
        {
          "field":"school"
        }
  }
}'

查詢結果：

{
  "took" : 4,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "11",
        "_score" : 1.0,
        "_source" : {
          "school" : "hkz"
        }
      }
    ]
  }
}

5）boolean filter：基於boolean邏輯來合併多個filter子句
　 must：其內部所有的子句條件必須同時匹配，即and；
查詢代碼：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "bool":{
          "must":[
          {"term":{"age":30}},
          {"term":{"name":"Guojing"}}]
       }
    }
}'

查詢結果：

{
  "took" : 3,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 0,
    "max_score" : null,
    "hits" : [ ]
  }
}

must_not：其所有子句至少有一個子句匹配，即or
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "bool":{
          "should":[
          {"term":{"name":"Yangguo"}},
          {"term":{"age":25}}]
       }
    }
}'

查詢結果：

{
  "took" : 3,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "3",
        "_score" : 1.0,
        "_source" : {
          "name" : "Yangguo",
          "age" : 25,
          "sex" : "M"
        }
      }
    ]
  }
}

must_not：其所有的子句必須都不匹配，即not
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "bool":{
          "must_not":[
          {"term":{"name":"Yangguo"}},
          {"term":{"sex":"F"}}]
       }
    }
}'

查詢結果：

{
  "took" : 4,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 11,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "5",
        "_score" : 1.0,
        "_source" : {
          "name" : "Xiaofeng",
          "age" : 30,
          "sex" : "M"
        }
      },

  "hits" : {
    "total" : 11,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "5",
        "_score" : 1.0,
        "_source" : {
          "name" : "Xiaofeng",
          "age" : 30,
          "sex" : "M"
        }
      },

6）prefix query：前綴字符串檢索匹配
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "prefix":{
           "name":"Guo"
       }
    }
}'

7）wildcard query：通配符檢索
匹配具有匹配通配符表達式(not analyzed)的字段的文檔。
支持的通配符：
　　1）*：匹配任何字符序列（包括空字符序列）；
　　2）？:匹配任何單個字符；
注意：次查詢可能會很慢，因爲它需要遍歷多個術語，爲了防止非常慢的通配符語句，通配符不能以任何一個通配符*或？開頭。
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "wildcard":{
           "name":"Guo*"
       }
    }
}'

8）regexp query：正則表達式檢索匹配
查詢語句：

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "regexp":{
           "name":"Guo.*"
       }
    }
}'

9）fuzzy query：模糊查詢查找再模糊度中指定的最大編輯距離內的所有可能的匹配項，然後檢查術語字典，以找出在檢索中實際存在待檢索的關鍵詞。

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "fuzzy":{
           "name":"Guo"
       }
    }
}'

10）type query：類型檢索

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "type":{
           "value":"numbers"
       }
    }
}'

11）ids query：返回指定id的全部信息

[root@node2 ~]# curl -XGET -H Content-Type:application/json 'localhost:9200/student/class1/_search?pretty' -d'{
    "query":{
       "ids":{
           "values":["1","2"]
       }
    }
}'
{
  "took" : 5,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 2,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "name" : "Huangrong",
          "age" : 28,
          "sex" : "F"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "name" : "Guojing",
          "age" : 30,
          "sex" : "M"
        }
      }
    ]
  }
}

12）全文檢索字段：對全文本指定匹配到的字段內容

[root@node1 ~]# curl -XGET -H Content-Type:application/json "localhost:9200/student/class1/_search?q=Xiaofeng"
{"took":12,"timed_out":false,"_shards":{"total":5,"successful":5,"skipped":0,"failed":0},"hits":{"total":1,"max_score":0.2876821,"hits":[{"_index":"student","_type":"class1","_id":"5","_score":0.2876821,"_source":{
    "name":"Xiaofeng",
    "age":30,
    "sex":"M"

DSL語句檢索方式：

[root@node1 ~]# curl -XGET -H Content-Type:application/json "localhost:9200/student/class1/_search?pretty"  -d '{
    "query":{
     "multi_match":{
        "query":"Xiaofeng"
     }
   }
}'
{
  "took" : 10,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : 0.2876821,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "5",
        "_score" : 0.2876821,
        "_source" : {
          "name" : "Xiaofeng",
          "age" : 30,
          "sex" : "M"
        }
      }
    ]
  }
}

13）指定字段查找匹配的字符內容

[root@node1 ~]# curl -XGET -H Content-Type:application/json "localhost:9200/student/class1/_search?q=sex:M"
{"took":6,"timed_out":false,"_shards":{"total":5,"successful":5,"skipped":0,"failed":0},"hits":{"total":3,"max_score":0.2876821,"hits":[{"_index":"student","_type":"class1","_id":"5","_score":0.2876821,"_source":{
    "name":"Xiaofeng",
    "age":30,
    "sex":"M"
}},{"_index":"student","_type":"class1","_id":"1","_score":0.2876821,"_source":{
    "name":"Guojing",
    "age":20,
    "sex":"M"
}},{"_index":"student","_type":"class1","_id":"3","_score":0.2876821,"_source":{
    "name":"Yangguo",
    "age":18,
    "sex":"M"
}}]}}

DSL語句指定字段檢索：

[root@node1 ~]# curl -XGET -H Content-Type:application/json  "localhost:9200/student/class1/_search?pretty" -d'{
>     "query":{
>       "match":{
>         "sex":"M"
>       }
>     }
> }'
{
  "took" : 7,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 3,
    "max_score" : 0.2876821,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "5",
        "_score" : 0.2876821,
        "_source" : {
          "name" : "Xiaofeng",
          "age" : 30,
          "sex" : "M"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "1",
        "_score" : 0.2876821,
        "_source" : {
          "name" : "Guojing",
          "age" : 20,
          "sex" : "M"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "3",
        "_score" : 0.2876821,
        "_source" : {
          "name" : "Yangguo",
          "age" : 18,
          "sex" : "M"
        }
      }
    ]
  }
}

14）在指定的多字段中檢索文檔

[root@node1 ~]# curl -XGET -H Content-Type:application/json  "localhost:9200/student/class1/_search?pretty" -d'{
    "query":{
      "multi_match":{
>        "query":"F",
>        "fields":["sex","name"]
>     }
>   }
> }'
{
  "took" : 9,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 3,
    "max_score" : 0.13353139,
    "hits" : [
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "2",
        "_score" : 0.13353139,
        "_source" : {
          "name" : "Huangrong",
          "age" : 18,
          "sex" : "F"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "4",
        "_score" : 0.13353139,
        "_source" : {
          "name" : "Xiaolongnv",
          "age" : 25,
          "sex" : "F"
        }
      },
      {
        "_index" : "student",
        "_type" : "class1",
        "_id" : "6",
        "_score" : 0.13353139,
        "_source" : {
          "name" : "Azhu",
          "age" : 24,
          "sex" : "F"
        }
      }
    ]
  }
}