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Commit 33c8a490 authored by gatorsmile's avatar gatorsmile Committed by Michael Armbrust
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[SPARK-12989][SQL] Delaying Alias Cleanup after ExtractWindowExpressions

JIRA: https://issues.apache.org/jira/browse/SPARK-12989

In the rule `ExtractWindowExpressions`, we simply replace alias by the corresponding attribute. However, this will cause an issue exposed by the following case:

```scala
val data = Seq(("a", "b", "c", 3), ("c", "b", "a", 3)).toDF("A", "B", "C", "num")
  .withColumn("Data", struct("A", "B", "C"))
  .drop("A")
  .drop("B")
  .drop("C")

val winSpec = Window.partitionBy("Data.A", "Data.B").orderBy($"num".desc)
data.select($"*", max("num").over(winSpec) as "max").explain(true)
```
In this case, both `Data.A` and `Data.B` are `alias` in `WindowSpecDefinition`. If we replace these alias expression by their alias names, we are unable to know what they are since they will not be put in `missingExpr` too.

Author: gatorsmile <gatorsmile@gmail.com>
Author: xiaoli <lixiao1983@gmail.com>
Author: Xiao Li <xiaoli@Xiaos-MacBook-Pro.local>

Closes #10963 from gatorsmile/seletStarAfterColDrop.
parent 6075573a
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