Wenzhe Zhou has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/15250 )

Change subject: IMPALA-6689: Speed up point lookup for Kudu primary key
......................................................................


Patch Set 3:

(2 comments)

http://gerrit.cloudera.org:8080/#/c/15250/2/fe/src/main/java/org/apache/impala/planner/KuduScanNode.java
File fe/src/main/java/org/apache/impala/planner/KuduScanNode.java:

http://gerrit.cloudera.org:8080/#/c/15250/2/fe/src/main/java/org/apache/impala/planner/KuduScanNode.java@288
PS2, Line 288:     inputCardinality_ = cardinality_ = kuduTable_.getNumRows();
             :     if (isPointLookupQuery_) {
             :       cardin
> Limit 0 is a common trick for determining the schema of a query without exe
set cardinality as min(1, kuduTable_.getNumRows())


http://gerrit.cloudera.org:8080/#/c/15250/2/fe/src/main/java/org/apache/impala/planner/KuduScanNode.java@395
PS2, Line 395:           if (rpcTable.getSchema().getColumn(colName).isKey()) {
> This is assuming that we don't have duplicate equality predicates assigned
Verified that planner will generate an empty plan node for query with 
duplicated equivalence predicate. Will add comment for the assumption.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I4631cd4d1a528a1152b5cdcb268426f2ba1a0c08
Gerrit-Change-Number: 15250
Gerrit-PatchSet: 3
Gerrit-Owner: Wenzhe Zhou <[email protected]>
Gerrit-Reviewer: Anurag Mantripragada <[email protected]>
Gerrit-Reviewer: Csaba Ringhofer <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Quanlong Huang <[email protected]>
Gerrit-Reviewer: Thomas Tauber-Marshall <[email protected]>
Gerrit-Reviewer: Tim Armstrong <[email protected]>
Gerrit-Reviewer: Wenzhe Zhou <[email protected]>
Gerrit-Comment-Date: Fri, 21 Feb 2020 00:47:56 +0000
Gerrit-HasComments: Yes

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