Qifan Chen has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/17637 )

Change subject: IMPALA-10766: Better selectivity for =,not distinct
......................................................................


Patch Set 5:

(3 comments)

Looks very good. Thanks a lot for the follow-up work!

http://gerrit.cloudera.org:8080/#/c/17637/5/fe/src/main/java/org/apache/impala/analysis/BinaryPredicate.java
File fe/src/main/java/org/apache/impala/analysis/BinaryPredicate.java:

http://gerrit.cloudera.org:8080/#/c/17637/5/fe/src/main/java/org/apache/impala/analysis/BinaryPredicate.java@250
PS5, Line 250: rChildIsNull
nit. Do we need to worry about left child is null here, or not since the left 
child is always a column reference?


http://gerrit.cloudera.org:8080/#/c/17637/5/fe/src/main/java/org/apache/impala/analysis/BinaryPredicate.java@280
PS5, Line 280: // For = and !=, all null values are false
             :           // For is distinct from null, all null values are false
             :           // For is not distinct from non-null, all null values 
are false
nit. may combine them into a single sentence:

For =, !=, "is distinct from null" and "is not distinct from non-null", all 
null values must be excluded.


http://gerrit.cloudera.org:8080/#/c/17637/5/fe/src/main/java/org/apache/impala/analysis/BinaryPredicate.java@284
PS5, Line 284: Operator.NOT_DISTINCT && rChildIsNull)
Another case here is "is distinct from not-null".



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: Ib8ec62f2355a7036125cc0d261b790644b9f4b60
Gerrit-Change-Number: 17637
Gerrit-PatchSet: 5
Gerrit-Owner: liuyao <[email protected]>
Gerrit-Reviewer: Aman Sinha <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Qifan Chen <[email protected]>
Gerrit-Reviewer: Zoltan Borok-Nagy <[email protected]>
Gerrit-Reviewer: liuyao <[email protected]>
Gerrit-Comment-Date: Fri, 09 Jul 2021 17:55:28 +0000
Gerrit-HasComments: Yes

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