[jira] [Created] (SPARK-33035) Updates the obsoleted entries of attribute mapping in QueryPlan#transformUpWithNewOutput

["Takeshi Yamamuro (Jira)" <ji...@apache.org>]

Takeshi Yamamuro created SPARK-33035:
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             Summary: Updates the obsoleted entries of attribute mapping in QueryPlan#transformUpWithNewOutput
                 Key: SPARK-33035
                 URL: https://issues.apache.org/jira/browse/SPARK-33035
             Project: Spark
          Issue Type: Bug
          Components: SQL
    Affects Versions: 3.0.1, 3.1.0
            Reporter: Takeshi Yamamuro


This ticket aims at fixing corner-case bugs in the `QueryPlan#transformUpWithNewOutput` that is used to propagate updated `ExprId`s in a bottom-up way. Let's say we have a rule to simply assign new `ExprId`s in a projection list like this;
{code}
case class TestRule extends Rule[LogicalPlan] {
  override def apply(plan: LogicalPlan): LogicalPlan = plan.transformUpWithNewOutput {
    case p @ Project(projList, _) =>
      val newPlan = p.copy(projectList = projList.map { _.transform {
        // Assigns a new `ExprId` for references
        case a: AttributeReference => Alias(a, a.name)()
      }}.asInstanceOf[Seq[NamedExpression]])

      val attrMapping = p.output.zip(newPlan.output)
      newPlan -> attrMapping
  }
}
{code}
Then, this rule is applied into a plan below;
{code}
(3) Project [a#5, b#6]
+- (2) Project [a#5, b#6]
   +- (1) Project [a#5, b#6]
      +- LocalRelation <empty>, [a#5, b#6]
{code}
In the first transformation, the rule assigns new `ExprId`s in `(1) Project` (e.g., a#5 AS a#7, b#6 AS b#8). In the second transformation, the rule corrects the input references of `(2) Project`  first by using attribute mapping given from `(1) Project` (a#5->a#7 and b#6->b#8) and then assigns new `ExprId`s (e.g., a#7 AS a#9, b#8 AS b#10). But, in the third transformation, the rule fails because it tries to correct the references of `(3) Project` by using incorrect attribute mapping (a#7->a#9 and b#8->b#10) even though the correct one is a#5->a#9 and b#6->b#10. 




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