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https://issues.apache.org/jira/browse/SPARK-18690?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15716182#comment-15716182
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Apache Spark commented on SPARK-18690:
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User 'zero323' has created a pull request for this issue:
https://github.com/apache/spark/pull/16123
> Backward compatibility of unbounded frames
> ------------------------------------------
>
> Key: SPARK-18690
> URL: https://issues.apache.org/jira/browse/SPARK-18690
> Project: Spark
> Issue Type: Improvement
> Components: PySpark, SQL
> Affects Versions: 2.1.0
> Reporter: Maciej Szymkiewicz
> Priority: Minor
>
> SPARK-17845 introduced constant values to mark unbounded frame. This can
> break backward compatibility on some systems:
> In Spark <= 2.0:
> - {{UNBOUNDED PRECEDING}} is {{-sys.maxisze}}
> - {{UNBOUNDED FOLLOWING}} is {{sys.maxisze}}
> On 64 bit systems {{-sys.maxisze}} is typically equal to (1 << 63) - 1, on
> 32 bit systems (1 << 31) - 1
> (https://docs.python.org/3/library/sys.html#sys.maxsize).
> After SPARK-17845 this values are
> - {{UNBOUNDED PRECEDING}} is -(1 << 63)
> - {{UNBOUNDED FOLLOWING}} is (1 << 63) - 1
> As a result on many systems current code won't no longer use UNBOUNDED
> PRECEDING frame.
> We can use following values to ensure backward compatibility:
> - {{UNBOUNDED PRECEDING}} = {{max(-sys.maxsize, _JAVA_MIN_LONG)}}
> - {{UNBOUNDED FOLLOWING}} = {{min(sys.maxsize, _JAVA_MAX_LONG)}}
> Pros:
> - Prevents hard to spot errors in the user code.
> Cons:
> - Unnecessary complicated rules in the Spark code.
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