silundong commented on PR #4840: URL: https://github.com/apache/calcite/pull/4840#issuecomment-4152946230
> decorrelating join's condition is harder and can complicate resulting tree sometime. on the other hand decorrelating filter is logically better Making `FilterJoinRule` handle correlated subqueries in JOIN ON condition would make the logic significantly more complex. In addition, the current subquery removal rule already provide a optimization, and their effect is essentially the same as pushing down correlated subqueries in ON condition. Considering the issues mentioned above, I would prefer to prohibit pushing down correlated subqueries. That said, if the issues above can all be addressed properly, that would also be good. But I suspect this would require more rounds of careful review. -- 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]
