How can I convert local ORC files to CSV?

问题

I have an ORC file on my local machine and I need any reasonable format from it (e.g. CSV, JSON, YAML, ...).

How can I convert ORC to CSV?

回答1:

1. Download
2. Extract the files, go to the java folder and execute maven: mvn install
3. Use ORC-Tools

This is how I use them - you will likely need to adjust the paths:

java -jar ~/.m2/repository/org/apache/orc/orc-tools/1.5.4/orc-tools-1.5.4-uber.jar data ~/your_file.orc > output.json

The output is JSON Lines which is easy to convert to CSV. First I needed to remove the last two lines from the output. Then:

import pandas as pd

df = pd.read_json('output.json', lines=True)
df.to_csv('output.csv')

来源：https://stackoverflow.com/questions/54482815/how-can-i-convert-local-orc-files-to-csv