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https://issues.apache.org/jira/browse/SPARK-54654?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18063675#comment-18063675
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Holden Karau commented on SPARK-54654:
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This seems more like a this is in ANSI-SQL so if we want to follow it no such 
luck. I could be wrong though (just looking at other vendors impls) 
[https://docs.vertica.com/23.4.x/en/sql-reference/data-types/data-type-coercion/]
 

> Dangerous automatic type coercion when spark.sql.ansi.enabled=true
> ------------------------------------------------------------------
>
>                 Key: SPARK-54654
>                 URL: https://issues.apache.org/jira/browse/SPARK-54654
>             Project: Spark
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 4.0.1, 3.5.7
>            Reporter: Jarno Rajala
>            Priority: Major
>
> The setting _*spark.sql.ansi.enabled=true*_ should enforce strict typing, 
> disallowing any potentially unsafe implicit type conversions. Right now it 
> doesn't.
> As _*spark.sql.ansi.enabled=true*_ by default since Spark 4.0, I think this 
> requires serious consideration and should be treated as a bug.
> Consider the behaviour of following queries when 
> *_spark.sql.ansi.enabled=true:_*
> {{SELECT 123='123';}}
> {{SELECT 123='123X';}}
> The first will succeed and returns _{*}true{*}._ The second will fail with a 
> hard error. The same issue exists with other operations, such as when using 
> {*}_coalesce()_{*}. 
> In complex setups, where data may come from various different sources and 
> passed through multiple tables, it can be hard to ensure strict typing 
> everywhere and numbers are likely to be passed in string typed columns 
> unintentionally. Typing errors may go uncaught for a considerable time until 
> a catastrophic runtime type mismatch occurs with the introduction of an 
> invalid non-numeric string at some point.
> It can also be hard to debug such issues as queries with a LIMIT clause may 
> succeed without errors, but the full query doesn't.



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