# Elasticsearch can-match phase

**URL:** <https://discuss.elastic.co/t/elasticsearch-can-match-phase/299331>\
**Category:** Elasticsearch\
**Created:** [March 10, 2022, 11:55am UTC](https://discuss.elastic.co/t/elasticsearch-can-match-phase/299331 "2022-03-10T11:55:10Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![qixian](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/qixian/32/97437_2.png) [@qixian](https://discuss.elastic.co/u/qixian)\
**Post date:** [March 10, 2022, 11:55am UTC](https://discuss.elastic.co/t/elasticsearch-can-match-phase/299331/1 "2022-03-10T11:55:11Z")

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hello,who can help me with this question,thanks.  
I konw that the old version of Elasticsearch before 7.16,during the can-match phase,the search’s coordinating node sent an individual request to each shard checked,is it contains the primary shard and replication shard ?

 ![微信图片_20220310195434](https://us1.discourse-cdn.com/elastic/original/3X/d/7/d7ca911aae9d7bb48013491a25ee77e89990351f.png)

and the other question is whether the can-match phase only return the document id and then send second request get the complete document?

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**Author:** ![qixian](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/qixian/32/97437_2.png) [@qixian](https://discuss.elastic.co/u/qixian)\
**Post date:** [March 11, 2022, 7:24am UTC](https://discuss.elastic.co/t/elasticsearch-can-match-phase/299331/2 "2022-03-11T07:24:09Z")

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I have analyze the source code of Elasticsearch old version，I think The first question should contains all shards primary and replication；The second question is after the can-match phase which is prefilter the shards and next will execute the search accoding to the query type, which contains query\_then\_fetch and dfs\_query\_then\_fetch

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**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [April 8, 2022, 7:24am UTC](https://discuss.elastic.co/t/elasticsearch-can-match-phase/299331/3 "2022-04-08T07:24:25Z")

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