如何在Elasticsearch中更新字段的现有数据类型？ （“没有在字段[名称]上声明类型[文本]的处理程序”）

Question

I am completely new to elasticsearch want to update one existing field datatype from "string" type to "text" type. I have tried but ended up getting this exception: "No handler for type [text] declared on field [Name]"

Any advice, my elasticsearch version -

{
  "name" : "Tej",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "raiQbq0ySUioBScsptsTzQ",
  "version" : {
    "number" : "2.4.4",
    "build_hash" : "fcbb46dfd45562a9cf00c604b30849a6dec6b017",
    "build_timestamp" : "2017-01-03T11:33:16Z",
    "build_snapshot" : false,
    "lucene_version" : "5.5.2"
  },
  "tagline" : "You Know, for Search"
}

Index Mapping detail -

{"customer":{"mappings":{"external":{"properties":{"Name":{"type":"string"},"age":{"type":"long"},"doc":{"properties":{"age":{"type":"long"},"name":{"type":"string"}}},"name":{"type":"string"}}}}}}

As per the doc - I used below command to update existing datatype

`curl -i -X PUT \
   -H "Content-Type:application/json" \
   -d \
'{
    "external" : {
        "properties" : {
            "Name" : {"type" : "text"}
        }
    }
}
' \
 'http://10.200.14.15:9200/customer/_mapping/external'`

response

{
    "error": {
        "root_cause": [
            {
                "type": "mapper_parsing_exception",
                "reason": "No handler for type [text] declared on field [Name]"
            }
        ],
        "type": "mapper_parsing_exception",
        "reason": "No handler for type [text] declared on field [Name]"
    },
    "status": 400
}

Answer 1

Any reason why you went for Elasticsearch 2.4.4. instead of 5.X? Judging by the name of your cluster, it is your personal one... Reason I ask, is that the string value is no longer in use in 5, and the mappings are done slightly different as well.

From personal experience, you cannot change the mapping of an existing field if it has any data in it. You should be able to update your mapping template with the new value, and any new template should be created with the new value.

If you want to change the type of an existing field, you will have to create a new index, with the new mapping and then migrate all data from the old one in the new one. Depending on the size, this can be quite a pain in the...

Answer 2

The reason you are getting this is because, the "Text" datatype is not supported in the 2.4 version of ElasticSearch.

Here is the complete list of supported datatypes:
https://www.elastic.co/guide/en/elasticsearch/reference/2.4/mapping-types.html

Either stick to "string" datatype or upgrade your ElasticSearch.