[[query-dsl-parent-id-query]]
=== Parent Id Query

The `parent_id` query can be used to find child documents which belong to a particular parent.
Given the following mapping definition:

[source,js]
--------------------------------------------
PUT my_index?include_type_name=true
{
  "mappings": {
    "_doc": {
      "properties": {
        "my_join_field": {
          "type": "join",
          "relations": {
            "my_parent": "my_child"
          }
        }
      }
    }
  }
}

PUT my_index/_doc/1?refresh
{
  "text": "This is a parent document",
  "my_join_field": "my_parent"
}

PUT my_index/_doc/2?routing=1&refresh
{
  "text": "This is a child document",
  "my_join_field": {
    "name": "my_child",
    "parent": "1"
  }
}

--------------------------------------------
// CONSOLE
// TESTSETUP

[source,js]
--------------------------------------------------
GET /my_index/_search
{
  "query": {
    "parent_id": {
      "type": "my_child",
      "id": "1"
    }
  }
}
--------------------------------------------------
// CONSOLE


==== Parameters

This query has two required parameters:

[horizontal]
`type`::  The **child** type name, as specified in the <<parent-join,`join` field>>.
`id`::    The ID of the parent document.

`ignore_unmapped`::  When set to `true` this will ignore an unmapped `type` and will not match any
documents for this query. This can be useful when querying multiple indexes
which might have different mappings. When set to `false` (the default value)
the query will throw an exception if the `type` is not mapped.