checkpoint: addressed Vinayak's review comments.
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 f1d79f2..14adbcc 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
@@ -250,7 +250,6 @@
physicalRewritesAllLevels.add(new EnforceStructuralPropertiesRule());
physicalRewritesAllLevels.add(new IntroHashPartitionMergeExchange());
physicalRewritesAllLevels.add(new SetClosedRecordConstructorsRule());
- //physicalRewritesAllLevels.add(new PullPositionalVariableFromUnnestRule());
physicalRewritesAllLevels.add(new PushProjectDownRule());
physicalRewritesAllLevels.add(new InsertProjectBeforeUnionRule());
physicalRewritesAllLevels.add(new IntroduceMaterializationForInsertWithSelfScanRule());