# NestedQuery: Filter \_source

**URL:** <https://discuss.elastic.co/t/nestedquery-filter--source/22531>\
**Category:** Elasticsearch\
**Created:** [March 5, 2015, 4:23pm UTC](https://discuss.elastic.co/t/nestedquery-filter--source/22531 "2015-03-05T16:23:58Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ku3ia](https://avatars.discourse-cdn.com/v4/letter/k/c89c15/32.png) [@ku3ia](https://discuss.elastic.co/u/ku3ia)\
**Post date:** [March 5, 2015, 4:23pm UTC](https://discuss.elastic.co/t/nestedquery-filter--source/22531/1 "2015-03-05T16:23:58Z")

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Hi all!  
I'm using nested mapping for my index. When I'm quering data with nested query elasticsearch returns whole \_source document.

For example, nested query

{  
"query": {  
"nested": {  
"path": "books",  
"query": {  
"term": {  
"books.category\_id": 2  
}  
}  
}  
}  
}

returns matched document with source:

\_source: {  
id: 1,  
author: me,  
books: [  
{  
title: title1,  
category\_id: 1  
},  
{  
title: title2,  
category\_id: 2  
}  
]  
}

I'm interesting, can results return only with matched category\_id, like

\_source: {  
id: 1,  
author: me,  
books: [  
{  
title: title2,  
category\_id: 2  
}  
]  
}

For example, in Apache Solr it can be done with ChildTransormer.  
Thanks for any help.

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 6, 2017, 12:28am UTC](https://discuss.elastic.co/t/nestedquery-filter--source/22531/2 "2017-07-06T00:28:19Z")

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