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risingwavelabs · Feb 7, 2024 · c709cb4 · c709cb4
1 parent 1fa68b0
commit c709cb4
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/frontend/src/optimizer/rule/pull_up_correlated_predicate_agg_rule.rs b/src/frontend/src/optimizer/rule/pull_up_correlated_predicate_agg_rule.rs
@@ -44,7 +44,7 @@ use crate::utils::{Condition, IndexSet};
 /// After:
 ///
 /// ```text
-///     LogicalApply [yyy = xxx]
+///     LogicalJoin [yyy = xxx]
 ///    /            \
 ///  LHS          Project
 ///                 |
@@ -144,6 +144,7 @@ impl Rule for PullUpCorrelatedPredicateAggRule {
         let new_bottom_proj: PlanRef = LogicalProject::new(filter, bottom_proj_exprs).into();
 
         // If there is a count aggregate, bail out and leave for general subquery unnesting to deal.
+        // When group by is empty, count would return 0 instead of null.
         if agg_calls
             .iter()
             .any(|agg_call| agg_call.agg_kind == AggKind::Count)