Removing Dynamic field

[Stefano_Bossi]

Dear forum,

I am dealing with a strange behaviour of Elastic Search; at least strange for me.
Let me explain:
I have indexed some data and ES inserted in dynamic mapping all the fields he found in the data, so far so good.
Now I have realised I don't need some documents any more (because they have dirty data) so I have used a POST like this to delete the documents containing those fields which are dirty:
POST radio/_delete_by_query

{
    "query": {
        "bool": {
            "must": [
                {
                    "exists": {
                        "field": "queryParams._"
                    }
                }
            ]
        }
    }
}

The dynamic mapping still includes the fields aren't any more present so I have deleted the Index Pattern and recreate it.
The strange thing here, for me, is that ES in the recreated Pattern still includes even the field "queryParams._" which isn't any more present in my docs.

Is there a way to get rid of the unwanted Pattern filed without reindexing all the docs?
Why the Index Pattern is still there ?

Regards,
Stefano Bossi

[dadoonet (David Pilato)]

Hi

You can not change the mapping of a field once it has been created.
The only way to get rid of it is by reindexing your dataset without this field in the mapping and in the documents of course.