Aleksandr Efimov has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/24605 )

Change subject: IMPALA-15195: Calcite Planner performance improvements for tpcds
......................................................................


Patch Set 8:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/24605/8/java/calcite-planner/src/main/java/org/apache/impala/calcite/schema/FilterSelectivityEstimator.java
File 
java/calcite-planner/src/main/java/org/apache/impala/calcite/schema/FilterSelectivityEstimator.java:

http://gerrit.cloudera.org:8080/#/c/24605/8/java/calcite-planner/src/main/java/org/apache/impala/calcite/schema/FilterSelectivityEstimator.java@267
PS8, Line 267:           return DEFAULT_IS_NULL_PERCENTAGE;
This changed behaviour for semi/anti joins between PS6 and PS8. It used to 
return null here, so getNullPercentage() fell through to the column-origin 
lookup and used the base table's null stats. Now it returns the 2% default 
instead. A SEMI join only exposes left-side columns and doesn't generate nulls, 
so the base-table stats look like the right answer there - this seems to lose 
information for any IN/EXISTS subquery. Intended, or should the semi/anti case 
still fall through?

Small nit while here: the TODO just above is a copy of the one at 280-282 and 
talks about equality conjunctions, but this branch keys off the join type, so 
it reads a bit confusingly.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I0ee6662dc6500ea6ebd9f859de4df1740c51a058
Gerrit-Change-Number: 24605
Gerrit-PatchSet: 8
Gerrit-Owner: Steve Carlin <[email protected]>
Gerrit-Reviewer: Aleksandr Efimov <[email protected]>
Gerrit-Reviewer: Aman Sinha <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Joe McDonnell <[email protected]>
Gerrit-Reviewer: Michael Smith <[email protected]>
Gerrit-Reviewer: Steve Carlin <[email protected]>
Gerrit-Comment-Date: Thu, 06 Aug 2026 19:37:26 +0000
Gerrit-HasComments: Yes

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