alamb commented on code in PR #4618:
URL: https://github.com/apache/arrow-datafusion/pull/4618#discussion_r1051118427
##########
datafusion/optimizer/src/optimizer.rs:
##########
@@ -147,6 +154,44 @@ pub struct Optimizer {
pub rules: Vec<Arc<dyn OptimizerRule + Send + Sync>>,
}
+/// If a rule is with `ApplyOrder`, it means the optimizer will derive to
handle children instead of
+/// recursively handling in rule.
+/// We just need handle a subtree pattern itself.
+///
+/// Notice: **sometime** result after optimize still can be optimized, we need
apply again.
+///
+/// Usage Example: Merge Limit (subtree pattern is: Limit-Limit)
Review Comment:
Thank you
--
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]
