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https://issues.apache.org/jira/browse/PARQUET-182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14637495#comment-14637495
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Alex Levenson commented on PARQUET-182:
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Hi [~stevemel]
Yes, I'm surprised nobody else has run into this, I don't know how many people
are using the unbound record filter, or if they are using it on optional
columns / nested schemas.
As a quick work-around, you could give the filter2 api a try. Have you seen
this API? It accomplishes the same goal, and also potentially applies filters
to metadata about chunks of data which can be a huge win in some cases.
> 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: 1.5.0, 1.6.0, 1.7.0
> Environment: Linux, Java7/Java8
> Reporter: Steven Mellinger
> Priority: Blocker
> Fix For: 1.9.0
>
>
> 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.
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