Is there a way to exclude a field in an Elasticsearch query

Question

I know to use the fields setting to include just the fields I want in a search http://www.elasticsearch.org/guide/reference/api/search/fields/

... but I was wondering if I could do the opposite ... somehow specify one or two fields that I don't want included in the query results (like an attachment, for example). It just seems painful to have to type out all the fields I want minus one or two, when I could just specify fields to exclude

Answer 1

You can use Source Filtering (Tested in v. 1.6 and v. 1.7): https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-source-filtering.html

{
    "_source": {
        "include": [ "obj1.*", "obj2.*" ],
        "exclude": [ "*.description" ]
    },
    "query" : {
        "term" : { "user" : "kimchy" }
    }
}

You can also use it in GET request:

curl "localhost:9200/myindex/mytype/66a8f299870b4cab?_source_exclude=file._content&pretty"

The previous example exclude the file content in an attachment field.

Answer 2

Did you see the documentation for ‛partial‛ on the same page you linked in your question? That allows you to do what you want, albeit only on ‛_source‛ fields I believe. See https://www.elastic.co/guide/en/elasticsearch/reference/1.7/search-request-fields.html

When loading data from _source, partial fields can be used to use wildcards to control what part of the _source will be loaded based on include and exclude patterns.

Both include and exclude support multiple patterns:

{
    "query" : {
        "match_all" : {}
    },
    "partial_fields" : {
        "partial1" : {
            "include" : ["obj1.obj2.*", "obj1.obj4.*"],
            "exclude" : "obj1.obj3.*"
        }
    }
}