Cannot read parquet file that was generated from nanoparquet
- Dominant language
- Java
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Description
### Describe the bug, including details regarding any error messages, version, and platform.
When trying to use `MessageColumnIO` to get a record reader, the following error occurs:
```
Exception in thread "main" java.lang.UnsupportedOperationException
at org.apache.parquet.column.values.ValuesReader.readInteger(ValuesReader.java:178)
at org.apache.parquet.column.impl.ColumnReaderBase$ValuesReaderIntIterator.nextInt(ColumnReaderBase.java:830)
at org.apache.parquet.column.impl.ColumnReaderBase.checkRead(ColumnReaderBase.java:663)
at org.apache.parquet.column.impl.ColumnReaderBase.consume(ColumnReaderBase.java:801)
at org.apache.parquet.column.impl.ColumnReaderImpl.consume(ColumnReaderImpl.java:30)
at org.apache.parquet.column.impl.ColumnReaderImpl.(ColumnReaderImpl.java:43)
at org.apache.parquet.column.impl.ColumnReadStoreImpl.getColumnReader(ColumnReadStoreImpl.java:80)
at org.apache.parquet.io.RecordReaderImplementation.(RecordReaderImplementation.java:282)
at org.apache.parquet.io.MessageColumnIO$1.visit(MessageColumnIO.java:141)
at org.apache.parquet.io.MessageColumnIO$1.visit(MessageColumnIO.java:105)
at org.apache.parquet.filter2.compat.FilterCompat$NoOpFilter.accept(FilterCompat.java:180)
at org.apache.parquet.io.MessageColumnIO.getRecordReader(MessageColumnIO.java:105)
```
I expected that this would work. Pyarrow for example can read the file.
Sample file can be found here:
[mtcars_np.zip](https://github.com/user-attachments/files/17649331/mtcars_np.zip)
Nanoparquet can be found here:
https://github.com/r-lib/nanoparquet
Version: 1.14.3
Platform: Linux
### Component(s)
Core
Contributor guide
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Research direction
Start with the stack trace at org.apache.parquet.column.values.ValuesReader.readInteger and the ColumnReaderBase integer-reading path, using the linked mtcars_np.zip file as the reproduction case. Inspect the file's encoding metadata and compare it with what parquet-java 1.14.3 expects; done means MessageColumnIO can read the nanoparquet-generated file without UnsupportedOperationException.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- java
- Domain
- data-engineering
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100