Skip to content

[SPARK-11949][SQL] Check bitmasks to set nullable property #10067

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

Closed
wants to merge 2 commits into from
Closed

[SPARK-11949][SQL] Check bitmasks to set nullable property #10067

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
69be01d
Check bitmasks to set nullable property.
viirya Dec 1, 2015
723d24a
For comment.
viirya Dec 1, 2015
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
13 changes: 9 additions & 4 deletions sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -223,10 +223,15 @@ class Analyzer(
case other => Alias(other, other.toString)()
}

// TODO: We need to use bitmasks to determine which grouping expressions need to be
// set as nullable. For example, if we have GROUPING SETS ((a,b), a), we do not need
// to change the nullability of a.
val attributeMap = groupByAliases.map(a => (a -> a.toAttribute.withNullability(true))).toMap
val nonNullBitmask = x.bitmasks.reduce(_ & _)

val attributeMap = groupByAliases.zipWithIndex.map { case (a, idx) =>
if ((nonNullBitmask & 1 << idx) == 0) {
(a -> a.toAttribute.withNullability(true))
} else {
(a -> a.toAttribute)
}
}.toMap
Copy link
Contributor

@yhuai yhuai Dec 1, 2015

Choose a reason for hiding this comment

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

c87531b#commitcomment-14712726 looks like a good idea.

Copy link
Member Author

@viirya viirya Dec 1, 2015

Choose a reason for hiding this comment

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

I think we did the same thing? I can't see the difference between this and @hvanhovell's suggestion?

Copy link
Contributor

@hvanhovell hvanhovell Dec 1, 2015

Choose a reason for hiding this comment

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

It is the same thing. I only suggested to aggregate the bitmap in advance: val nonNullBitmask = x.bitmasks.reduce(_ & _) and to use the nonNullBitmask to check for (non) nullability in the loop. It should be a tiny tiny tiny bit quicker (no re-iteration required , and less one closure).

Copy link
Member Author

@viirya viirya Dec 1, 2015

Choose a reason for hiding this comment

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

Thanks. That's cool. I updated this according to your suggestion.


val aggregations: Seq[NamedExpression] = x.aggregations.map {
// If an expression is an aggregate (contains a AggregateExpression) then we dont change
Expand Down