[ 
https://issues.apache.org/jira/browse/SPARK-47566?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

ASF GitHub Bot reassigned SPARK-47566:
--------------------------------------

    Assignee:     (was: Apache Spark)

> SubstringIndex
> --------------
>
>                 Key: SPARK-47566
>                 URL: https://issues.apache.org/jira/browse/SPARK-47566
>             Project: Spark
>          Issue Type: Sub-task
>          Components: SQL
>    Affects Versions: 4.0.0
>            Reporter: Milan Dankovic
>            Priority: Major
>              Labels: pull-request-available
>
> Enable collation support for the *SubstringIndex* built-in string function in 
> Spark. First confirm what is the expected behaviour for these functions when 
> given collated strings, and then move on to implementation and testing. One 
> way to go about this is to consider using {_}StringSearch{_}, an efficient 
> ICU service for string matching. Implement the corresponding unit tests 
> (CollationStringExpressionsSuite) and E2E tests (CollationSuite) to reflect 
> how this function should be used with collation in SparkSQL, and feel free to 
> use your chosen Spark SQL Editor to experiment with the existing functions to 
> learn more about how they work. In addition, look into the possible use-cases 
> and implementation of similar functions within other other open-source DBMS, 
> such as [PostgreSQL|https://www.postgresql.org/docs/].
>  
> The goal for this Jira ticket is to implement the *SubstringIndex* functions 
> so that they support all collation types currently supported in Spark. To 
> understand what changes were introduced in order to enable full collation 
> support for other existing functions in Spark, take a look at the Spark PRs 
> and Jira tickets for completed tasks in this parent (for example: Contains, 
> StartsWith, EndsWith).
>  
> Read more about ICU [Collation Concepts|http://example.com/] and 
> [Collator|http://example.com/] class, as well as _StringSearch_ using the 
> [ICU user 
> guide|https://unicode-org.github.io/icu/userguide/collation/string-search.html]
>  and [ICU 
> docs|https://unicode-org.github.io/icu-docs/apidoc/released/icu4j/com/ibm/icu/text/StringSearch.html].
>  Also, refer to the Unicode Technical Standard for string 
> [searching|https://www.unicode.org/reports/tr10/#Searching] and 
> [collation|https://www.unicode.org/reports/tr35/tr35-collation.html#Collation_Type_Fallback].



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org

Reply via email to