Fix reading parquet column with unused dictionary #15942
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A parquet file produced by Impala was found to have an empty dictionary which is not used in the encoding of data pages in the column. For such a case we cannot rely on ColumnChunkMetaData#hasDictionaryPage as that checks for whether the data pages are also encoded using the dictionary. This change removes usage of hasDictionaryPage to fix query failures with such files.
skrzypo987
approved these changes
Feb 2, 2023
sopel39
approved these changes
Feb 2, 2023
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Description
Fix reading parquet column with unused dictionary
A parquet file produced by Impala was found to have an empty dictionary
which is not used in the encoding of data pages in the column.
For such a case we cannot rely on
ColumnChunkMetaData#hasDictionaryPageas that checks for whether the data pages are also encoded using the dictionary.
This change removes usage of hasDictionaryPage to fix query failures with such files.
Additional context and related issues
E.g. error stacktrace
This is a regression from changes in PR #15374 in release 405.
File is produced by Impala and contains an empty unused dictionary in
op_umpnandop_telcolumnspages result.txt
footer_result.txt
Release notes
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(x) Release notes are required, with the following suggested text: