Mapping is the outline of the documents stored in an index. It defines the data type like geo_point or string and format of the fields present in the documents and rules to control the mapping of dynamically added fields.

PUT bankaccountdetails
{
   "mappings":{
      "properties":{
         "name": { "type":"text"}, "date":{ "type":"date"},
         "balance":{ "type":"double"}, "liability":{ "type":"double"}
      }
   }
 }

When we run the above code, we get the response as shown below −

{
   "acknowledged" : true,
   "shards_acknowledged" : true,
   "index" : "bankaccountdetails"
}

Field Data Types

Elasticsearch supports a number of different datatypes for the fields in a document. The
data types used to store fields in Elasticsearch are discussed in detail here.

Core Data Types

These are the basic data types such as text, keyword, date, long, double, boolean or ip,
which are supported by almost all the systems.

Complex Data Types

These data types are a combination of core data types. These include array, JSON object
and nested data type. An example of nested data type is shown below &minus

POST /tabletennis/_doc/1
{
   "group" : "players",
   "user" : [
      {
         "first" : "dave", "last" : "jones"
      },
      {
         "first" : "kevin", "last" : "morris"
      }
   ]
}

When we run the above code, we get the response as shown below −

{
   "_index" : "tabletennis",
   "_type" : "_doc",
   "_id" : "1",
   _version" : 2,
   "result" : "updated",
   "_shards" : {
      "total" : 2,
      "successful" : 1,
      "failed" : 0
   },
   "_seq_no" : 1,
   "_primary_term" : 1
}

Another sample code is shown below −

POST /accountdetails/_doc/1
{
   "from_acc":"7056443341", "to_acc":"7032460534",
   "date":"11/1/2016", "amount":10000
}

When we run the above code, we get the response as shown below −

{  "_index" : "accountdetails",
   "_type" : "_doc",
   "_id" : "1",
   "_version" : 1,
   "result" : "created",
   "_shards" : {
      "total" : 2,
      "successful" : 1,
      "failed" : 0
   },
   "_seq_no" : 1,
   "_primary_term" : 1
}

We can check the above document by using the following command −

GET /accountdetails/_mappings?include_type_name=false

Removal of Mapping Types

Indices created in Elasticsearch 7.0.0 or later no longer accept a _default_ mapping. Indices created in 6.x will continue to function as before in Elasticsearch 6.x. Types are
deprecated in APIs in 7.0.