Kurt Deschler has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/19682 )

Change subject: IMPALA-12006: Improve cardinality estimation for joins 
involving multiple conjuncts
......................................................................


Patch Set 1:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/19682/1/fe/src/main/java/org/apache/impala/planner/JoinNode.java
File fe/src/main/java/org/apache/impala/planner/JoinNode.java:

http://gerrit.cloudera.org:8080/#/c/19682/1/fe/src/main/java/org/apache/impala/planner/JoinNode.java@421
PS1, Line 421:         if 
(analyzer.getQueryOptions().isUse_multiplied_selectivity_for_join()) {
It would be more flexible to allow a correlation coefficient between 0-1 here 
instead of just 2 modes. The product would be divided by the coefficient then 
take the min of the (scaled) product and the inputs as the final cardinality. 
Coefficient 0 should result in the original min selectivity.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I845d778a58404af834f7501fc8157a5a4b4bcc35
Gerrit-Change-Number: 19682
Gerrit-PatchSet: 1
Gerrit-Owner: Aman Sinha <[email protected]>
Gerrit-Reviewer: Aman Sinha <[email protected]>
Gerrit-Reviewer: Csaba Ringhofer <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Kurt Deschler <[email protected]>
Gerrit-Reviewer: Quanlong Huang <[email protected]>
Gerrit-Comment-Date: Wed, 05 Apr 2023 13:44:57 +0000
Gerrit-HasComments: Yes

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