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ulysses-you · ulysses-you · commit 2f55ec034ade · 2020-11-17T22:36:58.000+08:00
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala
@@ -1451,6 +1451,7 @@ object PushPredicateThroughJoin extends Rule[LogicalPlan] with PredicateHelper {
 }
 
 /**
+ * This rule optimizes Limit operators by:
  * 1. Eliminate [[Limit]] operators if it's child max row <= limit.
  * 2. Combines two adjacent [[Limit]] operators into one, merging the
  *    expressions into one single expression.

Original file line number	Diff line number	Diff line change
`@@ -1451,6 +1451,7 @@ object PushPredicateThroughJoin extends Rule[LogicalPlan] with PredicateHelper {`
`1451`	`1451`	`}`
`1452`	`1452`
`1453`	`1453`	`/**`
	`1454`	`+ * This rule optimizes Limit operators by:`
`1454`	`1455`	`* 1. Eliminate [[Limit]] operators if it's child max row <= limit.`
`1455`	`1456`	`* 2. Combines two adjacent [[Limit]] operators into one, merging the`
`1456`	`1457`	`* expressions into one single expression.`