Bharath Vissapragada has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/12535 )

Change subject: IMPALA-8014: Incorrect FK/PK cardinality estimation
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Patch Set 4:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/12535/4/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/12535/4/fe/src/main/java/org/apache/impala/planner/JoinNode.java@416
PS4, Line 416: fkCard = Math.max(fkCard, largestKeyCard);
> Pardon my ignorance, isn't fkCard always >= largestKeyCard here? You are ju
Sorry, I meant you are multiplying all lhsNdv() for each slot and comparing it 
to the max among them. Generally I think the else {} block here could use an 
example.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: Id0db82564596b0a9271b89b8e3f7a3cf92d306da
Gerrit-Change-Number: 12535
Gerrit-PatchSet: 4
Gerrit-Owner: Paul Rogers <[email protected]>
Gerrit-Reviewer: Bharath Vissapragada <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Paul Rogers <[email protected]>
Gerrit-Reviewer: Tim Armstrong <[email protected]>
Gerrit-Comment-Date: Fri, 08 Mar 2019 18:27:37 +0000
Gerrit-HasComments: Yes

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