ES: 设置默认值

场景: 

   XX对象的告警个数字段是数字, 优先级字段是数字

  排序要求: 优先告警个数大->小, 其次优先级大->小

问题: 

告警个数字段不存在或者值为0的情况是等价的,排序上应该是平等的.

不应该存在0的大于字段不存在的

处理: 

    对没有告警个数字段的默认设置0 , 那么排序的时候才正确

    使用Missing - 给字段设置默认值

一般用于排序时，该字段没有值，使用missing赋值默认值，然后就用赋的值进行排序

GET indexname/_search
{
  
  "sort": [
    {
      "alarmNum": {
        "order": "asc",
        "missing": 0    -- 此字段不存在的时候, 值为0 . 与值0是一样排序 
      }
    },
    {
      "priority_code":{
        "order": "asc"
      }
    }
  ],

 "from":0,
 "size":100
}

unmapped_type - 容错不存在的字段

如果mapping中无此字段，则搜索请求将失败.unmapped_type选项允许您忽略没有mapping的字段，也不按它们排序。参数的值为该字段对应值的类型。

这种场景一般不存在.因为index至少有一条数据存在此字段有值,mapper里面就有

如何不报错?

GET project_base_info/_search
{
 
  "sort": [
    {
      "alarmNum1": {
        "order": "asc",
        "missing": 0,
        "unmapped_type":"long"  -- 有了此配置 ,mapper没有也不会报错
      }
    },
    {
      "project_priority_code":{
        "order": "asc"
      }
    }
  ],

 "from":0,
 "size":100
}

pipeline 设置默认值:属于前置设置默认值

在插入数据时候,给字段设置给默认值. 但问题是,后续也无法修改此字段. 这个应该很少有这个需求

PUT _ingest/pipeline/add_zcy_pipeline
{
  "processors": [
    {
      "set": {
        "field": "projectCode",
        "value": "10000000"
      }
    }
  ]
}

设置projectCode 默认值10000000

创建索引:
PUT projecy_zcy3
{
  "settings": {
    "refresh_interval": "1s",
    "number_of_shards": 1,
    "number_of_replicas": 1,
    "index":{
      "default_pipeline":"add_zcy_pipeline"
    }
  },
  "mappings": {
    "properties": {
      "id": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword"
          },
          "keylong": {
            "type": "long"
          }
        }
      },
      "projectCode": {
        "type": "text"
      },
      "projectName": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword"
          }
        }
      },
      "projectStatus": {
        "type": "keyword"
      }
    }
  }
}

插入数据
PUT projecy_zcy3/_doc/2
{
  "id":"1022",
  "projectName":"ssss"
}
结果:
 "_source" : {
          "projectCode" : "10000000",
          "id" : "1022",
          "projectName" : "ssss"
        }
PUT projecy_zcy3/_doc/2
{
  "id":"1022",
  "projectName":"ssss",
  "projectCode":"111"
}
结果还是
 "_source" : {
          "projectCode" : "10000000",
          "id" : "1022",
          "projectName" : "ssss"
        }

设置默认值--script执行批量

# 批量更新脚本
POST customer/_update_by_query
{
  "script": {
    "lang": "painless",
    "source": "if (ctx._source.major == null) {ctx._source.major = 'student'}"
  }
}

设置默认值--借助 pipeline script 更新

PUT _ingest/pipeline/update_pipeline
{
  "processors": [
    {
      "script": {
        "lang": "painless",
        "source": """
              if (ctx['major'] == null) {ctx['major'] = 'student'}
          """
      }
    }
  ]
}
POST customer/_doc/4
{
  "major":null
}
POST customer/_update_by_query?pipeline=update_pipeline
{
  "query": {
    "match_all": {}
  }
}