Steven Mellinger created PARQUET-182:
----------------------------------------
Summary: FilteredRecordReader skips rows it shouldn't for schema
with optional columns
Key: PARQUET-182
URL: https://issues.apache.org/jira/browse/PARQUET-182
Project: Parquet
Issue Type: Bug
Components: parquet-mr
Affects Versions: 1.6.0rc2, 1.5.0
Environment: Linux, Java7
Reporter: Steven Mellinger
Priority: Blocker
When using UnboundRecordFilter with nested AND/OR filters over OPTIONAL
columns, there seems to be a case with a mismatch between the current record's
column value and the value read during filtering.
The structure of my filter predicate that results in incorrect filtering is: (x
&& (y || z))
When I step through it with a debugger I can see that the value being read from
the ColumnReader inside my Predicate is different than the value for that row.
Looking deeper there seems to be a buffer with dictionary keys in
RunLenghBitPackingHybridDecoder (I am using RLE). There are only two different
keys in this array, [0,1], whereas my optional column has three different
values, [null,0,1]. If I had a column with values 5,10,10,null,10, and keys 0
-> 5 and 1 -> 10, the buffer would hold 0,1,1,1,0, and in the case that it
reads the last row, would return 0 -> 5.
So it seems that nothing is keeping track of where nulls appear.
Hope someone can take a look, as it is a blocker for my project.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
