20.四种常见的相关度分数优化方法

1、query-time boost

 

GET /forum/article/_search
{
  "query": {
    "bool": {
      "should": [
        {
          "match": {
            "title": {
              "query": "java spark",
              "boost": 2
            }
          }
        },
        {
          "match": {
            "content": "java spark"
          }
        }
      ]
    }
  }
}

2、重构查询结构

 

GET /forum/article/_search
{
  "query": {
    "bool": {
      "should": [
        {
          "match": {
            "content": "java"
          }
        },
        {
          "match": {
            "content": "spark"
          }
        },
        {
          "bool": {
            "should": [
              {
                "match": {
                  "content": "solution"
                }
              },
              {
                "match": {
                  "content": "beginner"
                }
              }
            ]
          }
        }
      ]
    }
  }
}

3、negative boost
搜索包含java,不包含spark的doc,但是这样子很死板
搜索包含java,尽量不包含spark的doc,如果包含了spark,不会说排除掉这个doc,而是说将这个doc的分数降低
包含了negative term的doc,分数乘以negative boost,分数降低

 

GET /forum/article/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "content": "java"
          }
        }
      ],
      "must_not": [
        {
          "match": {
            "content": "spark"
          }
        }
      ]
    }
  }
}

 

GET /forum/article/_search
{
  "query": {
    "boosting": {
      "positive": {
        "match": {
          "content": "java"
        }
      },
      "negative": {
        "match": {
          "content": "spark"
        }
      }, 
      "negative_boost": 0.2
    }
  }
}

4、constant_score
如果你压根不需要相关度分数评分,直接走constant_score加filter,所有的doc分数都是1,没有评分的概念了

 

GET /forum/article/_search
{
  "query": {
    "bool": {
      "should": [
        {
          "constant_score": {
            "query": {
              "match": {
                "title": "java"
              }
            }
          }
        },
        {
          "constant_score": {
            "query": {
              "match": {
                "title": "spark"
              }
            }
          }
        }
      ]
    }
  }
}

 

来源：CSDN

作者：远处的海亲吻着天

链接：https://blog.csdn.net/lm324114/article/details/104573124