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From "Michael Ho (Code Review)" <ger...@cloudera.org>
Subject [Impala-ASF-CR] IMPALA-6187: Fix missing conjuncts evaluation with empty projection
Date Tue, 28 Nov 2017 02:31:38 GMT
Hello Tim Armstrong, Alex Behm, Dan Hecht, 

I'd like you to reexamine a change. Please visit

    http://gerrit.cloudera.org:8080/8623

to look at the new patch set (#2).

Change subject: IMPALA-6187: Fix missing conjuncts evaluation with empty projection
......................................................................

IMPALA-6187: Fix missing conjuncts evaluation with empty projection

Previously, scanners will assume that there are no conjuncts associated
with a scan node for queries with no materialized slots (e.g. count(*)).
This is not necessarily the case as one can write queries such as
select count(*) from tpch.lineitem where rand() * 10 < 0; or
select count(*) from tpch.lineitem where rand() > <a partition column>.
In which case, the conjuncts should still be evaluated once per row.

This change fixes the problem in the short-circuit handling logic for
count(*) to evaluate the conjuncts once per row and only commits a row
to the output row batch if the conjuncts evaluate to true.

Testing done: Added the example above to the scanner test

Change-Id: Ib530f1fdcd2c6de699977db163b3f6eb38481517
---
M be/src/exec/hdfs-avro-scanner.cc
M be/src/exec/hdfs-parquet-scanner.cc
M be/src/exec/hdfs-rcfile-scanner.cc
M be/src/exec/hdfs-scanner.cc
M be/src/exec/hdfs-scanner.h
M be/src/exec/hdfs-sequence-scanner.cc
M be/src/exec/hdfs-text-scanner.cc
M be/src/exec/kudu-scanner.cc
M be/src/exec/kudu-scanner.h
M be/src/runtime/row-batch.cc
M testdata/workloads/functional-query/queries/QueryTest/kudu-scan-node.test
M testdata/workloads/functional-query/queries/QueryTest/scanners.test
12 files changed, 81 insertions(+), 19 deletions(-)


  git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/23/8623/2
-- 
To view, visit http://gerrit.cloudera.org:8080/8623
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: newpatchset
Gerrit-Change-Id: Ib530f1fdcd2c6de699977db163b3f6eb38481517
Gerrit-Change-Number: 8623
Gerrit-PatchSet: 2
Gerrit-Owner: Michael Ho <kwho@cloudera.com>
Gerrit-Reviewer: Alex Behm <alex.behm@cloudera.com>
Gerrit-Reviewer: Dan Hecht <dhecht@cloudera.com>
Gerrit-Reviewer: Michael Ho <kwho@cloudera.com>
Gerrit-Reviewer: Tim Armstrong <tarmstrong@cloudera.com>

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