【ElasticSearch（九）進階】Term精確數值查詢，match keyword精確文字查詢

阿新 • • 發佈：2021-08-24

【ElasticSearch（九）進階】Term精確數值查詢，match keyword精確文字查詢

一、Term精確數值查詢

term查詢，會返回那些在提供的欄位中包含確切資訊的文件內容。
查詢text欄位值，使用match。查詢精確數值，使用term。
為什麼避免使用term對text欄位進行查詢？

預設情況下，ES更改text欄位的值作為詞法分析的一部分。這會使查詢text欄位值的精確匹配變得困難。

查詢年齡是33歲的資料：

GET bank/_search
{
  "query":{
    "term":{
      "age": 33
    }
  }
}

返回結果：

{
  "took" : 1,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 50,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "bank",
        "_type" : "account",
        "_id" : "18",
        "_score" : 1.0,
        "_source" : {
          "account_number" : 18,
          "balance" : 4180,
          "firstname" : "Dale",
          "lastname" : "Adams",
          "age" : 33,
          "gender" : "M",
          "address" : "467 Hutchinson Court",
          "employer" : "Boink",
          "email" : "[email protected]",
          "city" : "Orick",
          "state" : "MD"
        }
      },
        。。。
    ]
  }
}

二、match keyword精確文字查詢

下面對比下match，match_phrase，match中的屬性加.keyword的區別

1.match 模糊查詢文字

會將address的文字拆分成詞，只要結果中包含有任意詞的文件，都可以被篩選出來。

GET bank/_search
{
  "query":{
    "match":{
      "address": "467 Hutchinson Court"
    }
  }
}

返回結果：

{
  "took" : 17,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 120,
      "relation" : "eq"
    },
    "max_score" : 14.617203,
    "hits" : [
      {
        "_index" : "bank",
        "_type" : "account",
        "_id" : "18",
        "_score" : 14.617203,
        "_source" : {
          "account_number" : 18,
          "balance" : 4180,
          "firstname" : "Dale",
          "lastname" : "Adams",
          "age" : 33,
          "gender" : "M",
          "address" : "467 Hutchinson Court",
          "employer" : "Boink",
          "email" : "[email protected]",
          "city" : "Orick",
          "state" : "MD"
        }
      },
      {
        "_index" : "bank",
        "_type" : "account",
        "_id" : "53",
        "_score" : 5.990829,
        "_source" : {
          "account_number" : 53,
          "balance" : 28101,
          "firstname" : "Kathryn",
          "lastname" : "Payne",
          "age" : 29,
          "gender" : "F",
          "address" : "467 Louis Place",
          "employer" : "Katakana",
          "email" : "[email protected]",
          "city" : "Harviell",
          "state" : "SD"
        }
      },
      {
        "_index" : "bank",
        "_type" : "account",
        "_id" : "56",
        "_score" : 2.1248586,
        "_source" : {
          "account_number" : 56,
          "balance" : 14992,
          "firstname" : "Josie",
          "lastname" : "Nelson",
          "age" : 32,
          "gender" : "M",
          "address" : "857 Tabor Court",
          "employer" : "Emtrac",
          "email" : "[email protected]",
          "city" : "Sunnyside",
          "state" : "UT"
        }
      },
     。。。
    ]
  }
}

2.match_phrase 短語查詢

將address的文字視為一個短語，不進行文字拆分，只要結果中包含這個短語的文件，都能被篩選出來。

GET bank/_search
{
  "query":{
    "match_phrase":{
      "address": "467 Hutchinson"
    }
  }
}

返回結果：

{
  "took" : 1,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq"
    },
    "max_score" : 12.492344,
    "hits" : [
      {
        "_index" : "bank",
        "_type" : "account",
        "_id" : "18",
        "_score" : 12.492344,
        "_source" : {
          "account_number" : 18,
          "balance" : 4180,
          "firstname" : "Dale",
          "lastname" : "Adams",
          "age" : 33,
          "gender" : "M",
          "address" : "467 Hutchinson Court",
          "employer" : "Boink",
          "email" : "[email protected]",
          "city" : "Orick",
          "state" : "MD"
        }
      }
    ]
  }
}

3.match中的屬性加.keyword

keyword精確查詢，只有結果中address屬性和address.keyword的值完全一致的文件，才能被篩選出來。

結合2和3，可以發現同樣的值，match_phrase 和 keyword的區別。

GET bank/_search
{
  "query":{
    "match":{
      "address.keyword": "467 Hutchinson"
    }
  }
}

返回結果：

{
  "took" : 4,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 0,
      "relation" : "eq"
    },
    "max_score" : null,
    "hits" : [ ]
  }
}

*我們一般規定：全文檢索欄位用 match,其他非text欄位匹配用term