You signed in with another tab or window. Reload to refresh your session.You signed out in another tab or window. Reload to refresh your session.You switched accounts on another tab or window. Reload to refresh your session.Dismiss alert
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
During PushDownProjection optimization, it does not properly account for distinct, as it will attempt to push directly through the distinct, from input plan:
Projection: data.id
Distinct:
Projection: data.id, data.data
TableScan: data
Will generate output plan:
Projection: data.id
Distinct:
TableScan: data projection=[id]
Where it has inadvertently removed the data.data projection during the push down and hence leading to incorrect distinct behaviour.
What changes are included in this PR?
Properly handle distincts during recursion in PushDownProjection, to 'restart' the traversal with all required columns (derived from schema of the distinct) rather than using the input required columns.
After fix, the above plan output will instead be:
Projection: data.id
Distinct:
TableScan: data projection=[id, data]
Benchmark runs are scheduled for baseline = ceff6cb and contender = c4f4dff. c4f4dff is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Skipped ⚠️ Benchmarking of arrow-datafusion-commits is not supported on ec2-t3-xlarge-us-east-2] ec2-t3-xlarge-us-east-2
[Skipped ⚠️ Benchmarking of arrow-datafusion-commits is not supported on test-mac-arm] test-mac-arm
[Skipped ⚠️ Benchmarking of arrow-datafusion-commits is not supported on ursa-i9-9960x] ursa-i9-9960x
[Skipped ⚠️ Benchmarking of arrow-datafusion-commits is not supported on ursa-thinkcentre-m75q] ursa-thinkcentre-m75q
Buildkite builds:
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python, R. Runs only benchmarks with cloud = True
test-mac-arm: Supported benchmark langs: C++, Python, R
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Which issue does this PR close?
Closes #4667
Rationale for this change
During PushDownProjection optimization, it does not properly account for distinct, as it will attempt to push directly through the distinct, from input plan:
Will generate output plan:
Where it has inadvertently removed the
data.dataprojection during the push down and hence leading to incorrect distinct behaviour.What changes are included in this PR?
Properly handle distincts during recursion in PushDownProjection, to 'restart' the traversal with all required columns (derived from schema of the distinct) rather than using the input required columns.
After fix, the above plan output will instead be:
Are these changes tested?
New unit test in push_down_projection
Are there any user-facing changes?