Bankim Bhavsar 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
> Instead of 'are not sorted(partially sorted within each tablet)',  I meant
This is my understanding, I'll check further within Kudu team.

When the predicate pushed to Kudu includes partition key columns then pruning 
using min-max filter will be done first eliminating bunch of files containing 
column values namely cfiles.

When the predicate doesn't include partition key columns then all column values 
will need to be scanned and as per current implementation for every column 
value first Bloom filter will be checked before checking for range/min-max 
values[1]. So in case of non-partition key columns whether min-max filter will 
help depends upon whether min-max filter values are simply min and max of the 
values inserted in the Bloom filter or not derived from the values inserted in 
the Bloom filter. For the former case, I agree supplying min-max filter with 
Bloom filter won't help.

[1] 
https://github.com/apache/kudu/blob/master/src/kudu/common/column_predicate.h#L332



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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 03:23:19 +0000
Gerrit-HasComments: Yes

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