[ARROW-16685] [Python] Using Python's set in inner Table.join has undeterministic behaviour

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 9.0.0
• Component/s: Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/32030
• Assignee: Alessandro Molina
• Reporter: Alenka Frim
• Created: 30/May/22 10:09
• Updated: 11/Jan/23 11:45
• Resolved: 02/Jun/22 10:58

Description

For the inner join of pa.Table we are using Python's set, which causes undeterministic behaviour. This should be fixed so that the ordering of the output columns is stable.

See:

• https://github.com/apache/arrow/pull/13260#issuecomment-1141906725 
• https://github.com/apache/arrow/runs/6615749316?check_suite_focus=true#step:6:5590

Issue Links

• links to: GitHub Pull Request #13281