Zoltan Borok-Nagy has uploaded this change for review. ( 
http://gerrit.cloudera.org:8080/16503


Change subject: IMPALA-9952: Fix page index filtering for empty pages
......................................................................

IMPALA-9952: Fix page index filtering for empty pages

As IMPALA-4371 and IMPALA-10186 points out, Impala might write
empty data pages. It usually does that when it has to write a bigger
page than the current page size. If we really need to write empty date
pages is a different question, but we need to handle them correctly
as there are already such files out there.

The corresponding Parquet offset index entries to empty data pages
are invalid PageLocation objects with 'compressed_page_size' = 0.
Before this commit Impala didn't ignore the empty page locations, but
generated a warning. Since invalid page index doesn't fail a scan
by default, Impala continued scanning the file with semi-initialized
page filtering. This resulted in 'Top level rows aren't in sync'
error, or a crash in DEBUG builds.

With this commit Impala ignores empty data pages and still able to
filter the rest of the pages. Also, if the page index is corrupt
for some other reason, Impala correctly resets the page filtering
logic and falls back to regular scanning.

Testing:
* Added unit test for empty data pages
* Added e2e test for empty data pages
* Added e2e test for invalid page index

Change-Id: I4db493fc7c383ed5ef492da29c9b15eeb3d17bb0
---
M be/src/exec/parquet/hdfs-parquet-scanner.cc
M be/src/exec/parquet/hdfs-parquet-scanner.h
M be/src/exec/parquet/parquet-common-test.cc
M be/src/exec/parquet/parquet-common.cc
M testdata/data/README
A testdata/data/alltypes_empty_pages.parquet
A testdata/data/alltypes_invalid_pages.parquet
M testdata/workloads/functional-query/queries/QueryTest/parquet-page-index.test
M tests/query_test/test_parquet_stats.py
9 files changed, 174 insertions(+), 23 deletions(-)



  git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/03/16503/1
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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: I4db493fc7c383ed5ef492da29c9b15eeb3d17bb0
Gerrit-Change-Number: 16503
Gerrit-PatchSet: 1
Gerrit-Owner: Zoltan Borok-Nagy <[email protected]>

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