Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

fix: Average expression in Comet Final should handle all null inputs from partial Spark aggregation #261

Merged
merged 1 commit into from
Apr 12, 2024
Merged

fix: Average expression in Comet Final should handle all null inputs from partial Spark aggregation #261

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
12 changes: 9 additions & 3 deletions core/src/execution/datafusion/expressions/avg.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -176,9 +176,15 @@ impl Accumulator for AvgAccumulator {
}

fn evaluate(&mut self) -> Result<ScalarValue> {
Ok(ScalarValue::Float64(
self.sum.map(|f| f / self.count as f64),
))
if self.count == 0 {
// If all input are nulls, count will be 0 and we will get null after the division.
// This is consistent with Spark Average implementation.
Ok(ScalarValue::Float64(None))
} else {
Ok(ScalarValue::Float64(
self.sum.map(|f| f / self.count as f64),
))
Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Actually the GroupsAccumulator below has correctly implemented this behavior. Only AvgAccumulator has this issue.

}
}

fn size(&self) -> usize {
Expand Down
15 changes: 15 additions & 0 deletions spark/src/test/scala/org/apache/comet/exec/CometAggregateSuite.scala
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -40,6 +40,21 @@ import org.apache.comet.CometSparkSessionExtensions.isSpark34Plus
class CometAggregateSuite extends CometTestBase with AdaptiveSparkPlanHelper {
import testImplicits._

test(
"Average expression in Comet Final should handle " +
"all null inputs from partial Spark aggregation") {
withTempView("allNulls") {
allNulls.createOrReplaceTempView("allNulls")
withSQLConf(
CometConf.COMET_ENABLED.key -> "true",
CometConf.COMET_EXEC_SHUFFLE_ENABLED.key -> "true",
CometConf.COMET_COLUMNAR_SHUFFLE_ENABLED.key -> "true") {
val df = sql("select sum(a), avg(a) from allNulls")
checkSparkAnswer(df)
}
}
}

test("Aggregation without aggregate expressions should use correct result expressions") {
withSQLConf(
CometConf.COMET_ENABLED.key -> "true",
Expand Down
Loading