# Elasticsearch case-insensitive SQL RLIKE

**URL:** <https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459>\
**Category:** Elasticsearch\
**Tags:** elastic-stack-sql\
**Created:** [March 6, 2020, 1:13pm UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459 "2020-03-06T13:13:36Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![gsahu25](https://avatars.discourse-cdn.com/v4/letter/g/53a042/32.png) [@gsahu25](https://discuss.elastic.co/u/gsahu25)\
**Post date:** [March 6, 2020, 1:13pm UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459/1 "2020-03-06T13:13:36Z")

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Hi,

I am trying for a case-insensitive RLIKE operation in elasticsearch SQL.  
E.g.  
WHERE column1 RLIKE '.\*Gop.\*'

I tried using LCASE, UCASE in WHERE clause on the field, but is giving below error.  
"root\_cause": [  
{  
"type": "sql\_illegal\_argument\_exception",  
"reason": "Scalar function [UCASE(column1)] not allowed (yet) as argument for RLIKE"  
}  
]

Thanks in advance.

Regards,  
Gopal

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**Author:** ![matriv](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/matriv/32/43656_2.png) [@matriv](https://discuss.elastic.co/u/matriv)\
**Post date:** [March 7, 2020, 4:08pm UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459/2 "2020-03-07T16:08:09Z")

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`LIKE` and `RLIKE` expressions are translated to [wildcard](https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-wildcard-query.html) and [regexp](https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-regexp-query.html) queries respectively. If we allowed the usage of scalar functions like `LCASE`/`UCASE`, then the query should be instead get translated into a [script query](https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-script-query.html) which, in general, would have much more poor performance compared to the already expensive regexp/wildcard queries.

A workaround to achieve your goal is to create case insensitive pattern manually:  
`WHERE column1 RLIKE '.*[g|G][o|O][p|P].*'`

You can find more info regarding the regexp pattern [here](https://www.elastic.co/guide/en/elasticsearch/reference/current/regexp-syntax.html#regexp-optional-operators).

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<div class="post-metadata">

**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:** [March 7, 2020, 4:58pm UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459/3 "2020-03-07T16:58:14Z")

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If you always want case-insensitive search you can probably add a lowercase normaliser to the mapping for the field in Elasticsearch.

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<div class="post-metadata">

**Author:** ![gsahu25](https://avatars.discourse-cdn.com/v4/letter/g/53a042/32.png) [@gsahu25](https://discuss.elastic.co/u/gsahu25)\
**Post date:** [March 8, 2020, 10:38am UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459/4 "2020-03-08T10:38:05Z")

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I am planning to use the lowercase normaliser.  
Is there a way to define the normaliser in template and automatically apply to all string field of the index?

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<div class="post-metadata">

**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:** [March 8, 2020, 10:53am UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459/5 "2020-03-08T10:53:48Z")

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Yes, you can create an index template where you define dynamic mapping.

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<div class="post-metadata">

**Author:** ![gsahu25](https://avatars.discourse-cdn.com/v4/letter/g/53a042/32.png) [@gsahu25](https://discuss.elastic.co/u/gsahu25)\
**Post date:** [March 8, 2020, 10:58am UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459/6 "2020-03-08T10:58:14Z")

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Could you share a sample?  
I am only able to find templates with normaliser for single column lowercase.

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<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:** [April 5, 2020, 10:58am UTC](https://discuss.elastic.co/t/elasticsearch-case-insensitive-sql-rlike/222459/7 "2020-04-05T10:58:19Z")

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