es - elasticsearch mapping - parameters - 3

世界上并没有完美的程序，但是我们并不因此而沮丧，因为写程序就是一个不断追求完美的过程。

问 ：coerce有什么特点？
答 ：

问 ：coerce如何使用？
答 ：

# coerce

PUT /coerce_test
{
  "settings" : {
    "index.mapping.coerce" : false
  },
  "mappings" : {
    "properties" : {
      "age_1" : {
        "type"   : "integer",
        "coerce" : true
      },
      "age_2" : {
        "type" : "integer"
      }
    }
  }
}

# 索引
POST /coerce_test/_doc/1
{
  "age_1" : "18",
  "age_2" : 18
}

# 索引 age_2 没有强转而报错
POST /coerce_test/_doc/2
{
  "age_1" : "18",
  "age_2" : "18"
}

# 结果
{
  "error" : {
    "root_cause" : [
      {
        "type" : "mapper_parsing_exception",
        "reason" : "failed to parse field [age_2] of type [integer] in document with id '2'. Preview of field's value: '18'"
      }
    ],
    "type" : "mapper_parsing_exception",
    "reason" : "failed to parse field [age_2] of type [integer] in document with id '2'. Preview of field's value: '18'",
    "caused_by" : {
      "type" : "illegal_argument_exception",
      "reason" : "Integer value passed as String"
    }
  },
  "status" : 400
}

# 索引
POST /coerce_test/_doc/3
{
  "age_1" : "18.03",
  "age_2" : 18
}

# 搜索
# 搜索
GET /coerce_test/_search
{
  "query" : {
    "term" : {
      "age_1" : {
        "value" : "18"
      }
    }
  }
}

# 结果
{
  "took" : 0,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 2,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "coerce_test",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "age_1" : "18",
          "age_2" : 18
        }
      },
      {
        "_index" : "coerce_test",
        "_type" : "_doc",
        "_id" : "3",
        "_score" : 1.0,
        "_source" : {
          "age_1" : "18.03",
          "age_2" : 18
        }
      }
    ]
  }
}