1、为帖子数据增加标题字段

  1. POST /forum/_bulk
  2. { "update": { "_id": "1"} }
  3. { "doc" : {"title" : "this is java and hadoop blog"} }
  4. { "update": { "_id": "2"} }
  5. { "doc" : {"title" : "this is java blog"} }
  6. { "update": { "_id": "3"} }
  7. { "doc" : {"title" : "this is hadoop blog"} }
  8. { "update": { "_id": "4"} }
  9. { "doc" : {"title" : "this is java and elasticsearch blog"} }
  10. { "update": { "_id": "5"} }
  11. { "doc" : {"title" : "this is python, spark, flink blog"} }
  12. { "update": { "_id": "6"} }
  13. { "doc" : {"title" : "this is java, flink blog"} }
  14. { "update": { "_id": "7"} }
  15. { "doc" : {"title" : "this is hadoop, kafka, storm blog"} }
  16. { "update": { "_id": "8"} }
  17. { "doc" : {"title" : "this is spark, elasticsearch, flink blog"} }
  18. { "update": { "_id": "9"} }
  19. { "doc" : {"title" : "this is elasticsearch and flink blog"} }
  20. { "update": { "_id": "10"} }
  21. { "doc" : {"title" : "this is spark, flink blog"} }
  22. { "update": { "_id": "11"} }
  23. { "doc" : {"title" : "this is spark, hadoop blog"} }

2、搜索标题中包含javaelasticsearchblog

这个,就跟之前的那个term query,不一样了。不是搜索exact value,是进行full text全文检索。
match query,是负责进行全文检索的。当然,如果要检索的field,是not_analyzed类型的,那么match query也相当于term query

GET /forum/_search
{
    "query": {
        "match": {
            "title": "java elasticsearch"
        }
    }
}

3、搜索标题中包含java和elasticsearch的blog

搜索结果精准控制的第一步:灵活使用and关键字,如果你是希望所有的搜索关键字都要匹配的,那么就用and,可以实现单纯match query无法实现的效果

GET /forum/_search
{
    "query": {
        "match": {
            "title": {
        "query": "java elasticsearch",
        "operator": "and"
           }
        }
    }
}

4、搜索包含java,elasticsearch,spark,hadoop,4个关键字中,至少3个的blog

控制搜索结果的精准度的第二步:指定一些关键字中,必须至少匹配其中的多少个关键字,才能作为结果返回

GET /forum/_search
{
  "query": {
    "match": {
      "title": {
        "query": "java elasticsearch spark hadoop",
        "minimum_should_match": "75%"
      }
    }
  }
}
GET /forum/_search
{
  "query": {
    "match": {
      "title": {
        "query": "java elasticsearch spark hadoop",
        "minimum_should_match": 3
      }
    }
  }
}

5、用bool组合多个搜索条件,来搜索title

GET /forum/_search
{
  "query": {
    "bool": {
      "must":     { "match": { "title": "java" }},
      "must_not": { "match": { "title": "spark"  }},
      "should": [
                  { "match": { "title": "hadoop" }},
                  { "match": { "title": "elasticsearch"   }}
      ]
    }
  }
}

6、bool组合多个搜索条件,如何计算relevance score

mustshould搜索对应的分数,加起来,除以must和should的总数
排名第一:java,同时包含should中所有的关键字,hadoop,elasticsearch
排名第二:java,同时包含should中的elasticsearch
排名第三:java,不包含should中的任何关键字
should是可以影响相关度分数的
must是确保说,谁必须有这个关键字,同时会根据这个must的条件去计算出document对这个搜索条件的relevance score
在满足must的基础之上,should中的条件,不匹配也可以,但是如果匹配的更多,那么document的relevance score就会更高

{
  "took": 6,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 3,
    "max_score": 1.3375794,
    "hits": [
      {
        "_index": "forum",
        "_type": "article",
        "_id": "4",
        "_score": 1.3375794,
        "_source": {
          "articleID": "QQPX-R-3956-#aD8",
          "userID": 2,
          "hidden": true,
          "postDate": "2017-01-02",
          "tag": [
            "java",
            "elasticsearch"
          ],
          "tag_cnt": 2,
          "view_cnt": 80,
          "title": "this is java, elasticsearch, hadoop blog"
        }
      },
      {
        "_index": "forum",
        "_type": "article",
        "_id": "1",
        "_score": 0.53484553,
        "_source": {
          "articleID": "XHDK-A-1293-#fJ3",
          "userID": 1,
          "hidden": false,
          "postDate": "2017-01-01",
          "tag": [
            "java",
            "hadoop"
          ],
          "tag_cnt": 2,
          "view_cnt": 30,
          "title": "this is java and elasticsearch blog"
        }
      },
      {
        "_index": "forum",
        "_type": "article",
        "_id": "2",
        "_score": 0.19856805,
        "_source": {
          "articleID": "KDKE-B-9947-#kL5",
          "userID": 1,
          "hidden": false,
          "postDate": "2017-01-02",
          "tag": [
            "java"
          ],
          "tag_cnt": 1,
          "view_cnt": 50,
          "title": "this is java blog"
        }
      }
    ]
  }
}

7、搜索java,hadoop,spark,elasticsearch,至少包含其中3个关键字

默认情况下,should是可以不匹配任何一个的,比如上面的搜索中,this is java blog,就不匹配任何一个should条件
但是有个例外的情况,如果没有must的话,那么should中必须至少匹配一个才可以
比如下面的搜索,should中有4个条件,默认情况下,只要满足其中一个条件,就可以匹配作为结果返回
但是可以精准控制,should的4个条件中,至少匹配几个才能作为结果返回

GET /forum/_search
{
  "query": {
    "bool": {
      "should": [
        { "match": { "title": "java" }},
        { "match": { "title": "elasticsearch"   }},
        { "match": { "title": "hadoop"   }},
    { "match": { "title": "spark"   }}
      ],
      "minimum_should_match": 3 
    }
  }
}

梳理一下学到的知识点
1、全文检索的时候,进行多个值的检索,有两种做法,match queryshould
2、控制搜索结果精准度:and operatorminimum_should_match