# Enrich documents by copying fields from another index

**URL:** https://discuss.elastic.co/t/enrich-documents-by-copying-fields-from-another-index/170882
**Category:** Elasticsearch
**Created:** [March 5, 2019, 11:39am UTC](https://discuss.elastic.co/t/enrich-documents-by-copying-fields-from-another-index/170882 "2019-03-05T11:39:53Z")
**Posts on this page:** 1
**Showing post:** 8

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### Author: ![val](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/val/32/138203_2.png) [@val](https://discuss.elastic.co/u/val)
#### Post date: [November 26, 2019, 9:19am UTC](https://discuss.elastic.co/t/enrich-documents-by-copying-fields-from-another-index/170882/8 "2019-11-26T09:19:51Z")

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Guys,

Actually, the feature you're asking for is coming in 7.5 via the new [enrich processor](https://www.elastic.co/guide/en/elasticsearch/reference/7.5/ingest-enriching-data.html), which kind of provides index-time JOIN capability.

The main idea is to set up an [enrich policy](https://www.elastic.co/guide/en/elasticsearch/reference/7.5/enrich-setup.html#create-enrich-policy) that will source data from your related indexes into a new "enrich index" and then you can leverage that "enrich index" in your ingest pipeline using an [enrich processor](https://www.elastic.co/guide/en/elasticsearch/reference/7.5/enrich-processor.html) in order to enrich your documents with related fields.

So, without going in too many details, here is how it works in practice:

1. You have an index `A` with fields (`a`, `b`, `c`, `d`) that you'd like to use for enriching your incoming documents
2. You define an enrich policy based on that index `A` and the "join" field `a`
3. You define an ingest pipeline with an enrich processor that will try to match field `z` of the incoming document against field `A.a` of the enrich index
4. If a match is found, your incoming document will get fields `b`, `c` and `d` from the index `A`. Note that it will also get the match field `a` that you can remove using a `remove` processor if needed.

That should pretty much work the way you expect. You can find a complete example [here](https://www.elastic.co/guide/en/elasticsearch/reference/7.5/match-enrich-policy-type.html). At the beginning, it will work for exact matches (i.e. `term` query) and geo matches (i.e. `geo_shape` query), but they will probably add new kind of matches (like [`range` matches](https://github.com/elastic/elasticsearch/issues/48988)) in the near future.

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_[View the full topic](https://discuss.elastic.co/t/enrich-documents-by-copying-fields-from-another-index/170882)._