elasticsearch attachments

gistfile1.js

// When I try to map a field to have type attachment:

curl -XPUT 'http://127.0.0.1:9200/myapp/?pretty=1'  -d '
{
   "mappings" : {
      "doc" : {
         "properties" : {
            "file" : {
               "type" : "attachment"
            }
         }
      }
   }
}
'

// I get:

{
  "error" : "IndexAlreadyExistsException[[myapp] Already exists]",
  "status" : 400
}

// is there a way to add this without deleting the index or 
// at least without deleting all the docs? Thanks in advance.