Doc value Fields
editDoc value Fields
editAllows to return the doc value representation of a field for each hit, for example:
GET /_search { "query" : { "match_all": {} }, "docvalue_fields" : [ "my_ip_field", { "field": "my_keyword_field" }, { "field": "my_date_field", "format": "epoch_millis" } ] }
the name of the field |
|
an object notation is supported as well |
|
the object notation allows to specify a custom format |
Doc value fields can work on fields that have doc-values enabled, regardless of whether they are stored
*
can be used as a wild card, for example:
GET /_search { "query" : { "match_all": {} }, "docvalue_fields" : [ { "field": "*_date_field", "format": "epoch_millis" } ] }
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 formats
editWhile most fields do not support custom formats, some of them do:
- Date fields can take any date format.
- Numeric fields accept a DecimalFormat pattern.
By default fields are formatted based on a sensible configuration that depends
on their mappings: long
, double
and other numeric fields are formatted as
numbers, keyword
fields are formatted as strings, date
fields are formatted
with the configured date
format, etc.
On its own, docvalue_fields
cannot be used to load fields in nested
objects — if a field contains a nested object in its path, then no data will
be returned for that docvalue field. To access nested fields, docvalue_fields
must be used within an inner_hits
block.