# Coordinating node - just enough information to perform aggregation **URL:** \ **Category:** Elasticsearch\ **Created:** [April 28, 2020, 3:52am UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070 "2020-04-28T03:52:16Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![nages](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/nages/32/46943_2.png) [@nages](https://discuss.elastic.co/u/nages)\ **Post date:** [April 28, 2020, 3:52am UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070/1 "2020-04-28T03:52:17Z")
I am going through the documentation to better understand the role of coordinating node, the different phases of search request - I come across a phase - > Each shard returns **just enough information** to the coordinating node What sort of information this phrase refers - "just enough information" ? If we had complex queries like bool queries, aggregation - I presume coordinating need to execute the same query again to aggregation the results globally, in that case, coordinate node will also have some come kind of lucene engine running to aggregate the results ? ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [April 28, 2020, 6:23am UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070/2 "2020-04-28T06:23:57Z")
No. the coordinating node only gets the result from each shard. It does not execute requests itself but merges the results coming from each shard. For example, each shard returns 10 hits. The coordinating node sorts them and returns to the user the best 10 hits. ---
**Author:** ![nages](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/nages/32/46943_2.png) [@nages](https://discuss.elastic.co/u/nages)\ **Post date:** [April 28, 2020, 8:27am UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070/3 "2020-04-28T08:27:57Z")
> [@nages](#): > > What sort of information this phrase refers - "just enough information" ? ok, so in this case, "just enough information" refers to scoring values ? ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [April 28, 2020, 10:11am UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070/4 "2020-04-28T10:11:05Z")
It refers to: scores, 10 hits, computed aggs I believe. ---
**Author:** ![nages](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/nages/32/46943_2.png) [@nages](https://discuss.elastic.co/u/nages)\ **Post date:** [April 28, 2020, 1:47pm UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070/5 "2020-04-28T13:47:32Z")
Got it, is there any article about what parameters will be part of " Just Enough Information? ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [April 28, 2020, 7:37pm UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070/6 "2020-04-28T19:37:04Z")
I can't remember if there's a blog post about it. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [May 26, 2020, 7:37pm UTC](https://discuss.elastic.co/t/coordinating-node-just-enough-information-to-perform-aggregation/230070/7 "2020-05-26T19:37:07Z")
This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.