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https://issues.apache.org/jira/browse/ARROW-2372?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16439885#comment-16439885
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Kyle Barron commented on ARROW-2372:
------------------------------------

Awesome thanks!

> ArrowIOError: Invalid argument
> ------------------------------
>
>                 Key: ARROW-2372
>                 URL: https://issues.apache.org/jira/browse/ARROW-2372
>             Project: Apache Arrow
>          Issue Type: Bug
>          Components: Python
>    Affects Versions: 0.8.0, 0.9.0
>         Environment: Ubuntu 16.04
>            Reporter: Kyle Barron
>            Priority: Major
>             Fix For: 0.9.1
>
>
> I get an ArrowIOError when reading a specific file that was also written by 
> pyarrow. Specifically, the traceback is:
> {code:python}
> >>> import pyarrow.parquet as pq
> >>> pq.ParquetFile('gaz2016zcta5distancemiles.parquet')
>  ---------------------------------------------------------------------------
>  ArrowIOError Traceback (most recent call last)
>  <ipython-input-18-149f11bf68a5> in <module>()
>  ----> 1 pf = pq.ParquetFile('gaz2016zcta5distancemiles.parquet')
> ~/local/anaconda3/lib/python3.6/site-packages/pyarrow/parquet.py in 
> _init_(self, source, metadata, common_metadata)
>  62 self.reader = ParquetReader()
>  63 source = _ensure_file(source)
>  ---> 64 self.reader.open(source, metadata=metadata)
>  65 self.common_metadata = common_metadata
>  66 self._nested_paths_by_prefix = self._build_nested_paths()
> _parquet.pyx in pyarrow._parquet.ParquetReader.open()
> error.pxi in pyarrow.lib.check_status()
> ArrowIOError: Arrow error: IOError: [Errno 22] Invalid argument
> {code}
> Here's a reproducible example with the specific file I'm working with. I'm 
> converting a 34 GB csv file to parquet in chunks of roughly 2GB each. To get 
> the source data:
> {code:bash}
> wget 
> https://www.nber.org/distance/2016/gaz/zcta5/gaz2016zcta5distancemiles.csv.zip
> unzip gaz2016zcta5distancemiles.csv.zip{code}
> Then the basic idea from the [pyarrow Parquet 
> documentation|https://arrow.apache.org/docs/python/parquet.html#finer-grained-reading-and-writing]
>  is instantiating the writer class; looping over chunks of the csv and 
> writing them to parquet; then closing the writer object.
>  
> {code:python}
> import numpy as np
> import pandas as pd
> import pyarrow as pa
> import pyarrow.parquet as pq
> from pathlib import Path
> zcta_file = Path('gaz2016zcta5distancemiles.csv')
> itr = pd.read_csv(
>     zcta_file,
>     header=0,
>     dtype={'zip1': str, 'zip2': str, 'mi_to_zcta5': np.float64},
>     engine='c',
>     chunksize=64617153)
> schema = pa.schema([
>     pa.field('zip1', pa.string()),
>     pa.field('zip2', pa.string()),
>     pa.field('mi_to_zcta5', pa.float64())])
> writer = pq.ParquetWriter('gaz2016zcta5distancemiles.parquet', schema=schema)
> print(f'Starting conversion')
> i = 0
> for df in itr:
>     i += 1
>     print(f'Finished reading csv block {i}')
>     table = pa.Table.from_pandas(df, preserve_index=False, nthreads=3)
>     writer.write_table(table)
>     print(f'Finished writing parquet block {i}')
> writer.close()
> {code}
> Then running this python script produces the file 
> {code:java}
> gaz2016zcta5distancemiles.parquet{code}
> , but just attempting to read the metadata with `pq.ParquetFile()` produces 
> the above exception.
> I tested this with pyarrow 0.8 and pyarrow 0.9. I assume that pandas would 
> complain on import of the csv if the columns in the data were not `string`, 
> `string`, and `float64`, so I think creating the Parquet schema in that way 
> should be fine.



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