# Joining queries

**URL:** <https://discuss.elastic.co/t/joining-queries/146272>\
**Category:** Elasticsearch\
**Created:** [August 28, 2018, 6:42am UTC](https://discuss.elastic.co/t/joining-queries/146272 "2018-08-28T06:42:14Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![amit.patra](https://avatars.discourse-cdn.com/v4/letter/a/34f0e0/32.png) [@amit.patra](https://discuss.elastic.co/u/amit.patra)\
**Post date:** [August 28, 2018, 6:42am UTC](https://discuss.elastic.co/t/joining-queries/146272/1 "2018-08-28T06:42:14Z")

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Hi,

I know that performing full SQL-style joins in a distributed system like Elasticsearch is prohibitively expensive.

So I am giving an example of from RDBMS concept. Can you please suggest that what will be the efficient data model to avoid join in elasticsearch.

A table name: country\_code and the structure is

`country_name` varchar(70) DEFAULT NULL,  
`country_code` varchar(8) DEFAULT NULL,  
`image` blob DEFAULT NULL,  
`country_phcode` varchar(8) DEFAULT NULL

Another table name : mms\_cri and the structure is

`id` varchar(100) NOT NULL,  
`direction` varchar(1) DEFAULT NULL,  
`country_code` varchar(60) DEFAULT NULL  
`SATELITE_NAME` varchar(60) DEFAULT NULL,  
`TERMINAL_TYPE` varchar(40) DEFAULT NULL,  
`T2TID` varchar(1024) DEFAULT NULL,  
`T2THOP` varchar(10) DEFAULT NULL,

In RDBMS , We join above two table using country\_code.

In the above case scenario , How efficient data modelling can be done ? Can you explain with an example.

Thanks,

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**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\
**Post date:** [August 28, 2018, 6:59am UTC](https://discuss.elastic.co/t/joining-queries/146272/2 "2018-08-28T06:59:03Z")

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Storing large blobs in Elasticsearch is not recommended, so assuming the `image` attribute is instead a path to there the blob is located, I would recommend simply denormalizing the data.

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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:** [September 25, 2018, 6:59am UTC](https://discuss.elastic.co/t/joining-queries/146272/3 "2018-09-25T06:59:08Z")

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