# Can transforms drop certain groups?

**URL:** <https://discuss.elastic.co/t/can-transforms-drop-certain-groups/231633>\
**Category:** Elasticsearch\
**Created:** [May 7, 2020, 10:45pm UTC](https://discuss.elastic.co/t/can-transforms-drop-certain-groups/231633 "2020-05-07T22:45:28Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Xavier\_Marti\_Bofill](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/xavier_marti_bofill/32/67923_2.png) [@Xavier\_Marti\_Bofill](https://discuss.elastic.co/u/Xavier_Marti_Bofill)\
**Post date:** [May 7, 2020, 10:45pm UTC](https://discuss.elastic.co/t/can-transforms-drop-certain-groups/231633/1 "2020-05-07T22:45:29Z")

</div>

Is it possible to instruct a transform to ignore certain groups based on some aggregation results?  
Say we have an ecommerce and we want to track the time-to-buy, grouped by session-id. We have records for first access and for actual sale.  
Most users don't end up buying, and I don't want my new index to be full of null values.

---

<div class="post-metadata">

**Author:** ![Hendrik\_Muhs](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/hendrik_muhs/32/25802_2.png) [@Hendrik\_Muhs](https://discuss.elastic.co/u/Hendrik_Muhs)\
**Post date:** [May 8, 2020, 7:58am UTC](https://discuss.elastic.co/t/can-transforms-drop-certain-groups/231633/2 "2020-05-08T07:58:58Z")

</div>

Hi,

transforms can feed into an ingest pipeline, you can use the [drop](https://www.elastic.co/guide/en/elasticsearch/reference/current/drop-processor.html) processor to prevent documents from getting indexed based on a condition, e.g. a field value.

Hope that helps.

---

<div class="post-metadata">

**Author:** ![Xavier\_Marti\_Bofill](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/xavier_marti_bofill/32/67923_2.png) [@Xavier\_Marti\_Bofill](https://discuss.elastic.co/u/Xavier_Marti_Bofill)\
**Post date:** [May 8, 2020, 12:07pm UTC](https://discuss.elastic.co/t/can-transforms-drop-certain-groups/231633/3 "2020-05-08T12:07:56Z")

</div>

Got it, thanks!

---

<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:** [June 5, 2020, 12:07pm UTC](https://discuss.elastic.co/t/can-transforms-drop-certain-groups/231633/4 "2020-06-05T12:07:57Z")

</div>

This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.