Doc value Fieldsedit

Allows to return the doc value representation of a field for each hit, for example:

GET /_search
{
    "query" : {
        "match_all": {}
    },
    "docvalue_fields" : [
        {
            "field": "my_ip_field", 
            "format": "use_field_mapping" 
        },
        {
            "field": "my_date_field",
            "format": "epoch_millis" 
        }
    ]
}

the name of the field

the special use_field_mapping format tells Elasticsearch to use the format from the mapping

date fields may use a custom format

Doc value fields can work on fields that are not stored.

Note that if the fields parameter specifies fields without docvalues it will try to load the value from the fielddata cache causing the terms for that field to be loaded to memory (cached), which will result in more memory consumption.

Custom formatsedit

While most fields do not support custom formats, some of them do: - Date fields can take any date format. - Numeric fields accept a DecimalFormat pattern.

All fields support the special use_field_mapping format, which tells Elasticsearch to use the mappings to figure out a default format.

Note

The default is currently to return the same output as script fields. However it will change in 7.0 to behave as if the use_field_mapping format was provided.