# MongoDBWriter to update some fields

**URL:** <https://forum.cloverdx.com/t/mongodbwriter-to-update-some-fields/1565>\
**Category:** CloverDX Platform\
**Created:** [January 29, 2015, 12:00am UTC](https://forum.cloverdx.com/t/mongodbwriter-to-update-some-fields/1565 "2015-01-29T00:00:00Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![micky](https://avatars.discourse-cdn.com/v4/letter/m/a5b964/32.png) [@micky](https://forum.cloverdx.com/u/micky)\
**Post date:** [January 29, 2015, 12:00am UTC](https://forum.cloverdx.com/t/mongodbwriter-to-update-some-fields/1565/1 "2015-01-29T00:00:00Z")

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Hi,

I have created a graph to update some fields of a mongoDB colllection. But while using MongoDBWriter it is updating the entire object instead of updating the particular field. Do I miss any settings/attribute to set.

Also while updating an array element , it should append to the existing array.

Thanks in advance!!!

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<div class="post-metadata">

**Author:** ![imriskal](https://avatars.discourse-cdn.com/v4/letter/i/b38774/32.png) [@imriskal](https://forum.cloverdx.com/u/imriskal)\
**Post date:** [January 30, 2015, 3:18pm UTC](https://forum.cloverdx.com/t/mongodbwriter-to-update-some-fields/1565/2 "2015-01-30T15:18:26Z")

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Hi Micky,

You probably miss “set” operator in your newValue property. Something like:

```auto
$out.0.collection = "dogs";
$out.0.query = '{ "_id" : { "$oid" : "5464b3d0aad8b71e2c2bc65f"} }';
$out.0.newValue = '{ $set:{ "dogName": "Frankie" }}';

```

You can find more information in [MongoDB documentation](http://docs.mongodb.org/manual/reference/method/db.collection.update/#example-update-specific-fields).

Hope this helps.