Dandandan commented on issue #17169: URL: https://github.com/apache/datafusion/issues/17169#issuecomment-3189945322
* Another thing is that datafusion will store the data for each unique combination, rather than only once for each unique value. For columns with larger data and muliple columns in group by it could save memory to dictionary encode the columns in the group by (I think there is an issue for it somewhere to explore the idea) and reference them using index * For queries like distinct it could be better to remove duplicates through sorting rather than to use hash aggregation. In a query like the example, it would make even more sense as the result needs to be sorted anyway -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org
