Convert Parquet to CSV

python csv command-line parquet
Joe picture Joe · Jul 6, 2018 · Viewed 22.6k times · Source

How to convert Parquet to CSV from a local file system (e.g. python, some library etc.) but WITHOUT Spark? (trying to find as simple and minimalistic solution as possible because need to automate everything and not much resources).

I tried with e.g. parquet-tools on my Mac but data output did not look correct.

Need to make output so that when data is not present in some columns - CSV will have corresponding NULL (empty column between 2 commas)..

Thanks.

Answer

Uwe L. Korn picture Uwe L. Korn · Jul 7, 2018

You can do this by using the Python packages pandas and pyarrow (pyarrow is an optional dependency of pandas that you need for this feature).

import pandas as pd
df = pd.read_parquet('filename.parquet')
df.to_csv('filename.csv')

When you need to make modifications to the contents in the file, you can standard pandas operations on df.

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