cloud-fan commented on a change in pull request #25215:
[SPARK-28445][SQL][Python] Fix error when PythonUDF is used in both group by
and aggregate expression
URL: https://github.com/apache/spark/pull/25215#discussion_r309992580
##########
File path:
sql/core/src/main/scala/org/apache/spark/sql/execution/python/ExtractPythonUDFs.scala
##########
@@ -81,6 +81,64 @@ object ExtractPythonUDFFromAggregate extends
Rule[LogicalPlan] {
}
}
+/**
+ * Extracts PythonUDFs in logical aggregate, which are used in grouping keys,
evaluate them
+ * before aggregate.
+ * This must be executed after `ExtractPythonUDFFromAggregate` rule and before
`ExtractPythonUDFs`.
+ */
+object ExtractGroupingPythonUDFFromAggregate extends Rule[LogicalPlan] {
+ private def hasScalarPythonUDF(e: Expression): Boolean = {
+ e.find(PythonUDF.isScalarPythonUDF).isDefined
+ }
+
+ private def extract(agg: Aggregate): LogicalPlan = {
+ val projList = new ArrayBuffer[NamedExpression]()
+ val groupingExpr = new ArrayBuffer[Expression]()
+ val attributeMap = mutable.HashMap[PythonUDF, NamedExpression]()
+
+ agg.groupingExpressions.foreach { expr =>
+ if (hasScalarPythonUDF(expr)) {
+ val newE = expr transformDown {
+ case p: PythonUDF =>
+ // This is just a sanity check, the rule PullOutNondeterministic
should
+ // already pull out those nondeterministic expressions.
+ assert(p.udfDeterministic, "Non-determinstic PythonUDFs should not
appear " +
+ "in grouping expression")
+ val alias = Alias(p, "groupingPythonUDF")()
+ projList += alias
+ attributeMap += ((p.canonicalized.asInstanceOf[PythonUDF],
alias.toAttribute))
Review comment:
nit: if a python udf is handled before, this will replace it with a new
attribute?
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
With regards,
Apache Git Services
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]