Steve Carlin has posted comments on this change. ( http://gerrit.cloudera.org:8080/24556 )
Change subject: IMPALA-15127: Support HBO for UnionNode cardinality ...................................................................... Patch Set 10: Code-Review+1 (1 comment) http://gerrit.cloudera.org:8080/#/c/24556/8/fe/src/main/java/org/apache/impala/planner/UnionNode.java File fe/src/main/java/org/apache/impala/planner/UnionNode.java: http://gerrit.cloudera.org:8080/#/c/24556/8/fe/src/main/java/org/apache/impala/planner/UnionNode.java@376 PS8, Line 376: StringBuilder sb = new StringBuilder(statsType.name()).append(":UnionNode:"); > I think it's still better than nothing. E.g. the following two queries only I can't say for sure if it's better than nothing because if the cardinality barely changes by adding N constants versus N+1 constants, then it's a missed opportunity to use HBO stats. A false negative rather than a false positive. But I won't argue this any further :) I don't think there's a right or wrong answer here. -- To view, visit http://gerrit.cloudera.org:8080/24556 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: Ie228f530bdcb171d3b717966673164bf9a4c45c8 Gerrit-Change-Number: 24556 Gerrit-PatchSet: 10 Gerrit-Owner: Quanlong Huang <[email protected]> Gerrit-Reviewer: Aleksandr Efimov <[email protected]> Gerrit-Reviewer: Aman Sinha <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Quanlong Huang <[email protected]> Gerrit-Reviewer: Steve Carlin <[email protected]> Gerrit-Comment-Date: Wed, 05 Aug 2026 13:58:39 +0000 Gerrit-HasComments: Yes
