Hello Bharath Vissapragada, Impala Public Jenkins,
I'd like you to reexamine a change. Please visit
http://gerrit.cloudera.org:8080/14036
to look at the new patch set (#3).
Change subject: IMPALA-8848: fix UNION missing input cardinality bug
......................................................................
IMPALA-8848: fix UNION missing input cardinality bug
If a UNION has children, and none of those children has
a known cardinality, then we can make no reasonable
estimate of the output cardinality, so the planner
should consider the output cardinality to be unknown.
The previous behaviour was to report a cardinality of
0, which is unsafe because the planner may make further
decisions under the incorrect assumption that the output
of the UNION is tiny.
Testing:
An existing CardinalityTest already tested this but had
the wrong estimate.
Change-Id: Ic3ed670ffb685d8ff24824933ca303f3219737bb
---
M fe/src/main/java/org/apache/impala/planner/UnionNode.java
M fe/src/test/java/org/apache/impala/planner/CardinalityTest.java
2 files changed, 27 insertions(+), 4 deletions(-)
git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/36/14036/3
--
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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: newpatchset
Gerrit-Change-Id: Ic3ed670ffb685d8ff24824933ca303f3219737bb
Gerrit-Change-Number: 14036
Gerrit-PatchSet: 3
Gerrit-Owner: Tim Armstrong <tarmstr...@cloudera.com>
Gerrit-Reviewer: Bharath Vissapragada <bhara...@cloudera.com>
Gerrit-Reviewer: Impala Public Jenkins <impala-public-jenk...@cloudera.com>
