GitHub user marmbrus opened a pull request:
https://github.com/apache/spark/pull/2109
[WIP][SPARK-3194][SQL] Add AttributeSet to fix bugs with invalid
comparisons of AttributeReferences
It is common to want to describe sets of attributes that are in various
parts of a query plan.
Github user SparkQA commented on the pull request:
https://github.com/apache/spark/pull/2109#issuecomment-53206312
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Github user SparkQA commented on the pull request:
https://github.com/apache/spark/pull/2109#issuecomment-53206395
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Github user SparkQA commented on the pull request:
https://github.com/apache/spark/pull/2109#issuecomment-53209466
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Github user SparkQA commented on the pull request:
https://github.com/apache/spark/pull/2109#issuecomment-53209493
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Github user chuxi commented on the pull request:
https://github.com/apache/spark/pull/2109#issuecomment-53225175
I think references is used for transformExpression in QueryPlan to make
sure the same attribute just traversed once when Analyzer is explaining the
Attributes in a
