Aman Sinha has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/15683 )

Change subject: IMPALA-3741 [part 2]: Push runtime bloom filter to Kudu
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Patch Set 3:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/15683/3/common/thrift/PlanNodes.thrift
File common/thrift/PlanNodes.thrift:

http://gerrit.cloudera.org:8080/#/c/15683/3/common/thrift/PlanNodes.thrift@124
PS3, Line 124:   BLOOM_MIN_MAX = 2
In the case of both Bloom and Min-Max filters, is the order of evaluation 
determined by Kudu ?  For columns that are not sorted (partially sorted within 
each tablet), the Min-Max filters could potentially not eliminate much and be 
wasted effort, so Bloom filter should be evaluated first.  On the other hand, 
for sorted columns,  it would make sense to apply Min-Max filters first since 
Bloom filter has false positives.

It seems that for a specific column, creating two types of filters would incur 
overhead during execution - since both have to be sent to coordinator and 
broadcast to executors.  Any thoughts on that ?



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I9100076f68ea299ddb6ec8bc027cac7a47f5d754
Gerrit-Change-Number: 15683
Gerrit-PatchSet: 3
Gerrit-Owner: Wenzhe Zhou <[email protected]>
Gerrit-Reviewer: Aman Sinha <[email protected]>
Gerrit-Reviewer: Bankim Bhavsar <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Thomas Tauber-Marshall <[email protected]>
Gerrit-Reviewer: Wenzhe Zhou <[email protected]>
Gerrit-Comment-Date: Fri, 10 Apr 2020 02:08:39 +0000
Gerrit-HasComments: Yes

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