Csaba Ringhofer has uploaded this change for review. ( 
http://gerrit.cloudera.org:8080/19506


Change subject: IMPALA-11924: Cap runtime filter NDV with build key NDV
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IMPALA-11924: Cap runtime filter NDV with build key NDV

Before this patch the NDV used for bloom filter sizing was based only
on the cardinality of the build side. This is ok for FK/PK joins but
can highly overestimate NDV if the build key column's NDV is smaller
than the number of rows.

This change takes the minimum of NDV (not changed by selectiveness)
and cardinality (reduced by selectiveness).

Testing:
- found no test for bloom filter sizes, only verified manually that
  the example in the ticket is fixed.

Change-Id: Idaa46789663cb2e6d29f518757d89c85ff8e4d1a
---
M fe/src/main/java/org/apache/impala/planner/RuntimeFilterGenerator.java
1 file changed, 19 insertions(+), 2 deletions(-)



  git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/06/19506/1
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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: Idaa46789663cb2e6d29f518757d89c85ff8e4d1a
Gerrit-Change-Number: 19506
Gerrit-PatchSet: 1
Gerrit-Owner: Csaba Ringhofer <[email protected]>

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