cloud-fan commented on a change in pull request #25204:
[SPARK-28441][SQL][Python] Fix error when PythonUDF is used in correlated
scalar subquery
URL: https://github.com/apache/spark/pull/25204#discussion_r305670236
##########
File path:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/subquery.scala
##########
@@ -318,17 +318,30 @@ object RewriteCorrelatedScalarSubquery extends
Rule[LogicalPlan] {
/**
* Statically evaluate an expression containing zero or more placeholders,
given a set
- * of bindings for placeholder values.
+ * of bindings for placeholder values, if the expression is evaluable. If it
is not,
+ * bind statically evaluated expression results to an expression.
*/
- private def evalExpr(expr: Expression, bindings: Map[ExprId, Option[Any]]) :
Option[Any] = {
+ private def bindingExpr(
+ expr: Expression,
+ bindings: Map[ExprId, Option[Expression]]): Option[Expression] = {
val rewrittenExpr = expr transform {
case r: AttributeReference =>
bindings(r.exprId) match {
- case Some(v) => Literal.create(v, r.dataType)
+ case Some(v) => v
case None => Literal.default(NullType)
}
}
- Option(rewrittenExpr.eval())
+ if (rewrittenExpr.find(_.isInstanceOf[PythonUDF]).isDefined) {
+ // SPARK-28441: `PythonUDF` can't be statically evaluated.
Review comment:
We can't call `Expression.eval(null)` if it's not foldable, otherwise
exception may be thrown:
1. `AttributeReference.eval(null)` fails with NPE
2. `Nondeterministic.eval(null)` fails because it needs to be initialized
first
Whatever hack we use, I'd expect it makes the expression foldable.
----------------------------------------------------------------
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]
