NGA-TRAN opened a new issue, #19655: URL: https://github.com/apache/datafusion/issues/19655
### Is your feature request related to a problem or challenge? We have a use case where the query groups by columns that are implicitly sorted, and we would like DataFusion to recognize that ordering so it can apply pipeline aggregation. Consider the following query: ```SQL SELECT ... FROM t GROUP BY a, b; ``` In our data, the input is explicitly sorted only by `a`. However, `b` is always unique within each `(a, b)` pair, which means the data is implicitly sorted by `(a, b)` even though only `a` appears in the physical sort order. If DataFusion could infer or be informed that the data is effectively sorted by (a, b), it would be able to use pipeline aggregation, resulting in better performance. This is related to https://github.com/apache/datafusion/issues/16899 ### Describe the solution you'd like We need to define and propagate the uniqueness-based sort order. ### Describe alternatives you've considered _No response_ ### Additional context _No response_ -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
