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https://issues.apache.org/jira/browse/SPARK-25039?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17261807#comment-17261807
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黄海升 commented on SPARK-25039:
-----------------------------
It is necessary that converting `StringType` value and `{{NumericType}}` value
to `DoubleType` value.
Here's an example:
```
'999999999999999999' > 0 ==>
cast('999999999999999999' as Int) > 0 ==>
null > 0 ==>
false
```
> Binary comparison behavior should refer to Teradata
> ---------------------------------------------------
>
> Key: SPARK-25039
> URL: https://issues.apache.org/jira/browse/SPARK-25039
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 3.1.0
> Reporter: Yuming Wang
> Priority: Major
>
> The main difference is:
> # When comparing a {{StringType}} value with a {{NumericType}} value, Spark
> converts the {{StringType}} data to a {{NumericType}} value. But Teradata
> converts the {{StringType}} data to a {{DoubleType}} value.
> # When comparing a {{StringType}} value with a {{DateType}} value, Spark
> converts the {{DateType}} data to a {{StringType}} value. But Teradata
> converts the {{StringType}} data to a {{DateType}} value.
>
> More details:
> https://github.com/apache/spark/blob/65a4bc143ab5dc2ced589dc107bbafa8a7290931/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/TypeCoercion.scala#L120-L149
> https://www.info.teradata.com/HTMLPubs/DB_TTU_16_00/index.html#page/SQL_Reference/B035-1145-160K/lrn1472241011038.html
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