reflect PushDownLimitRule -> CopyDownLimitRule name change
diff --git a/asterix-algebra/src/main/java/edu/uci/ics/asterix/optimizer/base/RuleCollections.java b/asterix-algebra/src/main/java/edu/uci/ics/asterix/optimizer/base/RuleCollections.java
index d1006c7..118a7ac 100644
--- a/asterix-algebra/src/main/java/edu/uci/ics/asterix/optimizer/base/RuleCollections.java
+++ b/asterix-algebra/src/main/java/edu/uci/ics/asterix/optimizer/base/RuleCollections.java
@@ -90,7 +90,7 @@
 import edu.uci.ics.hyracks.algebricks.rewriter.rules.PullSelectOutOfEqJoin;
 import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushAssignBelowUnionAllRule;
 import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushAssignDownThroughProductRule;
-import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushLimitDownRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.CopyLimitDownRule;
 import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushNestedOrderByUnderPreSortedGroupByRule;
 import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushProjectDownRule;
 import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushSelectDownRule;
@@ -271,7 +271,7 @@
     public final static List<IAlgebraicRewriteRule> buildPhysicalRewritesTopLevelRuleCollection() {
         List<IAlgebraicRewriteRule> physicalRewritesTopLevel = new LinkedList<IAlgebraicRewriteRule>();
         physicalRewritesTopLevel.add(new PushNestedOrderByUnderPreSortedGroupByRule());
-        physicalRewritesTopLevel.add(new PushLimitDownRule());
+        physicalRewritesTopLevel.add(new CopyLimitDownRule());
         physicalRewritesTopLevel.add(new IntroduceProjectsRule());
         physicalRewritesTopLevel.add(new SetAlgebricksPhysicalOperatorsRule());
         physicalRewritesTopLevel.add(new IntroduceRapidFrameFlushProjectAssignRule());