elasticsearch 基于文章点赞数计算评分

POST news_index/_bulk
{"index":{"_id":1}}
{"title":"ElasticSearch原理- 神一样的存在"}
{"index":{"_id":2}}
{"title":"Elasticsearch 快速开始","like":5}
{"index":{"_id":3}}
{"title":"开源搜索与分析· Elasticsearch","like":10}
{"index":{"_id":4}}
{"title":"铭毅天下 死磕Elasticsearch", "like":1000}



GET news_index/_search
{
  "query": {
    "function_score": {
      "query": {
        "match": {
          "title": "Elasticsearch"
        }
      },
      "field_value_factor": {
        "field": "like",
        "modifier": "log1p",
        "factor": 0.1,
        "missing": 1
      },
      "boost_mode": "sum"
    }
  }
}

• 
  评分计算公式解读：new_score = old_score + log(1 + 0.1 * like值)
• missing含义：使用 field_value_factor 时要注意，有的文档可能会缺少这个字段，加上 missing 来个这些缺失字段的文档一个缺省值