Skip the creation of DistinctLimitNode for global aggregation node #437
Conversation
This file contains 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
kokosing
reviewed
Mar 11, 2019
| @@ -40,7 +40,7 @@ | |||
| */ | |||
| private static boolean isDistinct(AggregationNode node) | |||
| { | |||
| return node.getAggregations().isEmpty() && | |||
| return node.getAggregations().isEmpty() && !node.getGroupingKeys().isEmpty() && | |||
There was a problem hiding this comment.
Please move each condition to separate line
| @@ -40,7 +40,7 @@ | |||
| */ | |||
There was a problem hiding this comment.
Please add tests for queries that were failing previously.
If you are solving prestodb/presto#11276, then please add below query to io.prestosql.tests.AbstractTestAggregations or AbstractTestQueries:
select count(1) from (select sum(field1) from table limit 10) a;
| @@ -134,7 +134,7 @@ public PlanNode visitAggregation(AggregationNode node, RewriteContext<LimitConte | |||
| LimitContext limit = context.get(); | |||
|
|
|||
| if (limit != null && | |||
| node.getAggregations().isEmpty() && | |||
| node.getAggregations().isEmpty() && !node.getGroupingKeys().isEmpty() && | |||
There was a problem hiding this comment.
Please move each condition to separate line
Praveen2112
force-pushed
the
skip_distinct_limit
branch
from
01734cf
to
020dd0f
Compare
|
@kokosing Have resolved the above comments. |
kokosing
approved these changes
Mar 11, 2019
Praveen2112
force-pushed
the
skip_distinct_limit
branch
from
020dd0f
to
c72e056
Compare
martint
requested changes
Mar 11, 2019
| p.limit( | ||
| 1, | ||
| p.aggregation( | ||
| (Consumer<PlanBuilder.AggregationBuilder>) aggregationBuilder -> { |
There was a problem hiding this comment.
The type declaration for the lambda is unnecessary. You can also chain the invocations and shorten the variable name to reduce verbosity:
p.aggregation(builder -> builder
.singleGroupingSet(p.symbol("foo"))
.source(p.values(p.symbol("foo"))))))| @Test | ||
| public void testAggregationWithConstantArgumentsOverScalar() | ||
| { | ||
| assertQuery("SELECT count(1) FROM (SELECT count(custkey) FROM orders LIMIT 10) a"); |
There was a problem hiding this comment.
Extra space between FROM and orders
Praveen2112
force-pushed
the
skip_distinct_limit
branch
from
c72e056
to
3955b22
Compare
|
@martint I have updated the changes |
martint
approved these changes
Mar 12, 2019
Currently if there is a global aggregation node with no aggregation functions and if we try to merge with a limit node we end up creating a DistinctLimitNode which fails when executed because there is no grouping key. So we skip the creation of `DistinctLimitNode` for such aggregation nodes.
Praveen2112
force-pushed
the
skip_distinct_limit
branch
from
3955b22
to
854e814
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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.
Currently if there is a global aggregation node with no aggregation functions and if we try to merge with a limit node we end up creating a
DistinctLimitNodewhich fails when executed because there is no grouping key. So we skip the creation ofDistinctLimitNodefor such aggregationnodes.
This is will solve this issue (prestodb/presto#11276).