Elasticsearch学习搜索的笔记

1.普通查询(全文搜索)
查询name=Smith的文档数据
GET /megacorp/employee/_search
{
    "query" : {
        "match" : {
            "name" : "smith"
        }
    }
}
备注：
返回结果当中存在max_score和每个记录当中的_score表示最大相关性分数和该记录的相关性分数

2.组合查询
查询name=smith并且年龄大于30岁
GET /megacorp/employee/_search?pretty
{
    "query" : {
        "bool": {
            "must": {
                "match" : {
                    "name" : "smith" 
                }
            },
            "filter": {
                "range" : {
                    "age" : { "gt" : 30 } 
                }
            }
        }
    }
}

3.短语搜索
查询about字段当中包含rock和climbing并且rock climbing相连
GET /megacorp/employee/_search?pretty
{
    "query" : {
        "match_phrase" : {
            "about" : "rock climbing"
        }
    }
}

4.高亮搜索
GET /megacorp/employee/_search?pretty
{
    "query" : {
        "match_phrase" : {
            "about" : "rock climbing"
        }
    },
    "highlight": {
        "fields" : {
            "about" : {}
        }
    }
}

5.聚合查询-分析
按照interests字段进行聚合
GET /megacorp/employee/_search?pretty
{
  "aggs": {
    "all_interests": {
      "terms": { "field": "interests" }
    }
  }
}
报错：illegal_argument_exception
原因：Fielddata is disabled on text fields by default
解决办法:
PUT /megacorp/_mapping/employee
{
   "employee": {
      "properties": {
        "interests": {
          "type": "text",
          "fielddata": true
        }
      }
   }
}
备注:
interests是要聚合的字段名
查询结果当中all_interests是分析结果

6.分级汇总-分析
按照interests字段进行聚合，然后计算age平均年龄
GET /megacorp/employee/_search
{
    "aggs" : {
        "all_interests" : {
            "terms" : { "field" : "interests" },
            "aggs" : {
                "avg_age" : {
                    "avg" : { "field" : "age" }
                }
            }
        }
    }
}
备注：
avg_age是聚合结果当中新增字段