Skip to content

Add comment for AddDistinctForSemiJoinBuild optimizer #25254

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

Merged
feilong-liu merged 1 commit into from
Jun 6, 2025
Merged

Add comment for AddDistinctForSemiJoinBuild optimizer #25254

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
23 changes: 23 additions & 0 deletions ...main/java/com/facebook/presto/sql/planner/iterative/rule/AddDistinctForSemiJoinBuild.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -34,6 +34,29 @@
import static com.facebook.presto.spi.plan.AggregationNode.singleGroupingSet;
import static com.facebook.presto.sql.planner.plan.Patterns.semiJoin;

/**
* Add a distinct aggregation under the build side of semi join, for example:
* Rewrite query from
* <pre>
* - SemiJoin
* l.col in r.col
* - scan l
* col
* - scan r
* col
* </pre>
* into
* <pre>
* - SemiJoin
* l.col in r.col
* - scan l
* col
* - Aggregate
* group by r.col
* - scan r
* col
* </pre>
*/
public class AddDistinctForSemiJoinBuild
implements Rule<SemiJoinNode>
{
Expand Down
Loading