adriangb commented on code in PR #16641:
URL: https://github.com/apache/datafusion/pull/16641#discussion_r2180250971
##########
datafusion/physical-optimizer/src/enforce_sorting/sort_pushdown.rs:
##########
@@ -668,6 +668,15 @@ fn handle_hash_join(
plan: &HashJoinExec,
parent_required: OrderingRequirements,
) -> Result<Option<Vec<Option<OrderingRequirements>>>> {
+ // Anti-joins (LeftAnti or RightAnti) do not preserve meaningful input
order,
+ // so sorting beforehand cannot be relied on. Bail out early for both
flavors:
+ match plan.join_type() {
+ JoinType::LeftAnti | JoinType::RightAnti => {
+ return Ok(None);
+ }
+ _ => {}
+ }
Review Comment:
amazing!
> you can't push down a a limit below any operator that changes the
cardinality of the data
one question here: can we push down operators that have a limit (`LIMIT`
itself but also `TopK`) past other operators that change cardinality? e.g.
`HashJoinExec`? I feel like maybe what we should do is call
`ExecutionPlan::cardinality_effect` on the plan we are pushing down and the
plan we are pushing through and only allow the pushdown if they are both
`CardinalityEffect::Equal`.
--
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
