elasticsearch学习笔记高级篇（四）——在案例中实战使用terms搜索多个值以及多值搜索结果优化

格式描述：

term格式：

    "term": {
      "FIELD": {
        "value": "VALUE"
      }
     

terms格式：

    "terms": {
      "FIELD": [
        "VALUE1",
        "VALUE2"
      ]
    }

对于terms，如果和SQL语句联系起来的话，那么就相当于in

准备数据：

POST /forum/_bulk
{ "index": { "_id": 1 }}
{ "articleID" : "XHDK-A-1293-#fJ3", "userID" : 1, "hidden": false, "postDate": "2017-01-01" }
{ "index": { "_id": 2 }}
{ "articleID" : "KDKE-B-9947-#kL5", "userID" : 1, "hidden": false, "postDate": "2017-01-02" }
{ "index": { "_id": 3 }}
{ "articleID" : "JODL-X-1937-#pV7", "userID" : 2, "hidden": false, "postDate": "2017-01-01" }
{ "index": { "_id": 4 }}
{ "articleID" : "QQPX-R-3956-#aD8", "userID" : 2, "hidden": true, "postDate": "2017-01-02" }

1、为帖子字段增加tag字段

POST /forum/_bulk
{ "update": { "_id": "1"} }
{ "doc" : {"tag" : ["java", "hadoop"]} }
{ "update": { "_id": "2"} }
{ "doc" : {"tag" : ["java"]} }
{ "update": { "_id": "3"} }
{ "doc" : {"tag" : ["hadoop"]} }
{ "update": { "_id": "4"} }
{ "doc" : {"tag" : ["java", "elasticsearch"]} }

2、 搜索articleID为KDKE-B-9947-#kL5或QQPX-R-3956-#aD8的帖子

GET /forum/_search
{
  "query": {
    "constant_score": {
      "filter": {
        "terms": {
          "articleID": [
            "KDKE-B-9947-#kL5",
            "QQPX-R-3956-#aD8"
          ]
        }
      }
    }
  }
}

输出：

{
  "took" : 179,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 2,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "forum",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "articleID" : "KDKE-B-9947-#kL5",
          "userID" : 1,
          "hidden" : false,
          "postDate" : "2017-01-02",
          "tag" : [
            "java"
          ]
        }
      },
      {
        "_index" : "forum",
        "_type" : "_doc",
        "_id" : "4",
        "_score" : 1.0,
        "_source" : {
          "articleID" : "QQPX-R-3956-#aD8",
          "userID" : 2,
          "hidden" : true,
          "postDate" : "2017-01-02",
          "tag" : [
            "java",
            "elasticsearch"
          ]
        }
      }
    ]
  }
}

3、搜索tag中包含java的帖子

GET /forum/_search
{
  "query": {
    "constant_score": {
      "filter": {
        "terms": {
          "tag": [
            "java"
          ]
        }
      }
    }
  }
}

{
  "took" : 0,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 3,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "forum",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "articleID" : "XHDK-A-1293-#fJ3",
          "userID" : 1,
          "hidden" : false,
          "postDate" : "2017-01-01",
          "tag" : [
            "java",
            "hadoop"
          ]
        }
      },
      {
        "_index" : "forum",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "articleID" : "KDKE-B-9947-#kL5",
          "userID" : 1,
          "hidden" : false,
          "postDate" : "2017-01-02",
          "tag" : [
            "java"
          ]
        }
      },
      {
        "_index" : "forum",
        "_type" : "_doc",
        "_id" : "4",
        "_score" : 1.0,
        "_source" : {
          "articleID" : "QQPX-R-3956-#aD8",
          "userID" : 2,
          "hidden" : true,
          "postDate" : "2017-01-02",
          "tag" : [
            "java",
            "elasticsearch"
          ]
        }
      }
    ]
  }
}

4、优化搜索结果，仅仅搜索tag中只包含java的帖子

更新数据增加tag字段包含的标签数量

POST /forum/_bulk
{ "update": { "_id": "1"} }
{ "doc" : {"tag_cnt" : 2} }
{ "update": { "_id": "2"} }
{ "doc" : {"tag_cnt" : 1} }
{ "update": { "_id": "3"} }
{ "doc" : {"tag_cnt" : 1} }
{ "update": { "_id": "4"} }
{ "doc" : {"tag_cnt" : 2} }

GET /forum/_search
{
  "query": {
    "constant_score": {
      "filter": {
        "bool": {
          "must": [
            {
              "terms": {
                "tag": ["java"]
              }
            },
            {
              "term": {
                "tag_cnt": 1
              }
            }
          ]
        }
      }
    }
  }
}

{
  "took" : 192,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "forum",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "articleID" : "KDKE-B-9947-#kL5",
          "userID" : 1,
          "hidden" : false,
          "postDate" : "2017-01-02",
          "tag" : [
            "java"
          ],
          "tag_cnt" : 1
        }
      }
    ]
  }
}