[
https://issues.apache.org/jira/browse/SPARK-25942?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Wenchen Fan resolved SPARK-25942.
---------------------------------
Resolution: Fixed
Fix Version/s: 3.0.0
Issue resolved by pull request 22944
[https://github.com/apache/spark/pull/22944]
> Aggregate expressions shouldn't be resolved on AppendColumns
> ------------------------------------------------------------
>
> Key: SPARK-25942
> URL: https://issues.apache.org/jira/browse/SPARK-25942
> Project: Spark
> Issue Type: Bug
> Components: SQL
> Affects Versions: 2.4.0
> Reporter: Liang-Chi Hsieh
> Assignee: Liang-Chi Hsieh
> Priority: Major
> Fix For: 3.0.0
>
>
> Dataset.groupByKey will bring in new attributes from serializer. If key type
> is the same as original Dataset's object type, they have same serializer
> output and so the attribute names will conflict.
> This won't be a problem at most of cases, if we don't refer conflict
> attributes:
> {code:java}
> val ds: Dataset[(ClassData, Long)] = Seq(ClassData("one", 1),
> ClassData("two", 2)).toDS()
> .map(c => ClassData(c.a, c.b + 1))
> .groupByKey(p => p).count()
> {code}
> But if we use conflict attributes, `Analyzer` will complain about ambiguous
> references:
> {code}
> val ds = Seq(1, 2, 3).toDS()
> val agg = ds.groupByKey(_ >= 2).agg(sum("value").as[Long], sum($"value" +
> 1).as[Long])
> {code}
>
> {code:java}
> org.apache.spark.sql.AnalysisException: Reference 'value' is ambiguous, could
> be: value, value.;
> [info] at
> org.apache.spark.sql.catalyst.expressions.package$AttributeSeq.resolve(package.scala:247)
> [info] at
> org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.resolveChildren(LogicalPlan.scala:101)
> [info] at
> org.apache.spark.sql.catalyst.analysis.Analyzer$ResolveReferences$$anonfun$38.apply(Analyzer.scala:889)
> [info] at
> org.apache.spark.sql.catalyst.analysis.Analyzer$ResolveReferences$$anonfun$38.apply(Analyzer.scala:891)
> ...
> {code}
> Based on the API document and implementation details of
> KeyValueGroupedDataset, we should not allow aggregate expressions on
> KeyValueGroupedDataset to access key attributes.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org
