diff --git a/.gitignore b/.gitignore
index 1108a44..d748fde 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,4 +4,7 @@
 .project
 ClusterControllerService
 asterix-app/rttest
-asterix-app/mdtest
\ No newline at end of file
+asterix-app/mdtest/
+asterix-app/opttest/
+build
+asterix_logs
\ No newline at end of file
diff --git a/asterix-algebra/src/main/java/edu/uci/ics/asterix/translator/AqlExpressionToPlanTranslator.java b/asterix-algebra/src/main/java/edu/uci/ics/asterix/translator/AqlExpressionToPlanTranslator.java
index eed0f80..09fc2b9 100644
--- a/asterix-algebra/src/main/java/edu/uci/ics/asterix/translator/AqlExpressionToPlanTranslator.java
+++ b/asterix-algebra/src/main/java/edu/uci/ics/asterix/translator/AqlExpressionToPlanTranslator.java
@@ -196,7 +196,7 @@
 
             List<Mutable<ILogicalExpression>> writeExprList = new ArrayList<Mutable<ILogicalExpression>>(1);
             writeExprList.add(new MutableObject<ILogicalExpression>(new VariableReferenceExpression(resVar)));
-            ResultSetSinkId rssId = new ResultSetSinkId(metadataProvider.getResultSetId(), resultNodeName);
+            ResultSetSinkId rssId = new ResultSetSinkId(metadataProvider.getResultSetId());
             ResultSetDataSink sink = new ResultSetDataSink(rssId, null);
             topOp = new DistributeResultOperator(writeExprList, sink);
             topOp.getInputs().add(new MutableObject<ILogicalOperator>(project));
diff --git a/asterix-app/src/main/java/edu/uci/ics/asterix/api/common/AsterixHyracksIntegrationUtil.java b/asterix-app/src/main/java/edu/uci/ics/asterix/api/common/AsterixHyracksIntegrationUtil.java
index d207acb..272050f 100644
--- a/asterix-app/src/main/java/edu/uci/ics/asterix/api/common/AsterixHyracksIntegrationUtil.java
+++ b/asterix-app/src/main/java/edu/uci/ics/asterix/api/common/AsterixHyracksIntegrationUtil.java
@@ -48,6 +48,7 @@
         ncConfig1.clusterNetIPAddress = "127.0.0.1";
         ncConfig1.dataIPAddress = "127.0.0.1";
         ncConfig1.datasetIPAddress = "127.0.0.1";
+        ncConfig1.resultHistorySize = 1000;
         ncConfig1.nodeId = NC1_ID;
         ncConfig1.appNCMainClass = NCApplicationEntryPoint.class.getName();
         nc1 = new NodeControllerService(ncConfig1);
@@ -59,6 +60,7 @@
         ncConfig2.clusterNetIPAddress = "127.0.0.1";
         ncConfig2.dataIPAddress = "127.0.0.1";
         ncConfig2.datasetIPAddress = "127.0.0.1";
+        ncConfig2.resultHistorySize = 1000;
         ncConfig2.nodeId = NC2_ID;
         ncConfig2.appNCMainClass = NCApplicationEntryPoint.class.getName();
         nc2 = new NodeControllerService(ncConfig2);
diff --git a/asterix-app/src/main/java/edu/uci/ics/asterix/result/ResultReader.java b/asterix-app/src/main/java/edu/uci/ics/asterix/result/ResultReader.java
index 48bde1c..48ba0b1 100644
--- a/asterix-app/src/main/java/edu/uci/ics/asterix/result/ResultReader.java
+++ b/asterix-app/src/main/java/edu/uci/ics/asterix/result/ResultReader.java
@@ -19,7 +19,7 @@
 import edu.uci.ics.asterix.common.config.GlobalConfig;
 import edu.uci.ics.hyracks.api.client.IHyracksClientConnection;
 import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
-import edu.uci.ics.hyracks.api.dataset.DatasetDirectoryRecord.Status;
+import edu.uci.ics.hyracks.api.dataset.DatasetJobRecord.Status;
 import edu.uci.ics.hyracks.api.dataset.IHyracksDataset;
 import edu.uci.ics.hyracks.api.dataset.IHyracksDatasetReader;
 import edu.uci.ics.hyracks.api.dataset.ResultSetId;
diff --git a/asterix-app/src/test/java/edu/uci/ics/asterix/test/metadata/MetadataTest.java b/asterix-app/src/test/java/edu/uci/ics/asterix/test/metadata/MetadataTest.java
index 6339c07..dfbd305 100644
--- a/asterix-app/src/test/java/edu/uci/ics/asterix/test/metadata/MetadataTest.java
+++ b/asterix-app/src/test/java/edu/uci/ics/asterix/test/metadata/MetadataTest.java
@@ -15,12 +15,16 @@
 package edu.uci.ics.asterix.test.metadata;
 
 import java.io.File;
-import java.util.List;
+import java.util.ArrayList;
+import java.util.Collection;
 
 import org.apache.commons.io.FileUtils;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameters;
 
 import edu.uci.ics.asterix.api.common.AsterixHyracksIntegrationUtil;
 import edu.uci.ics.asterix.common.config.GlobalConfig;
@@ -30,13 +34,15 @@
 /**
  * Executes the Metadata tests.
  */
+@RunWith(Parameterized.class)
 public class MetadataTest {
 
+    private TestCaseContext tcCtx;
+
     private static final String PATH_ACTUAL = "mdtest/";
     private static final String PATH_BASE = "src/test/resources/metadata/";
     private static final String TEST_CONFIG_FILE_NAME = "asterix-build-configuration.xml";
     private static final String WEB_SERVER_PORT = "19002";
-    private static List<TestCaseContext> testCaseCollection;
 
     @BeforeClass
     public static void setUp() throws Exception {
@@ -51,8 +57,7 @@
         }
 
         AsterixHyracksIntegrationUtil.init();
-        TestCaseContext.Builder b = new TestCaseContext.Builder();
-        testCaseCollection = b.build(new File(PATH_BASE));
+
     }
 
     @AfterClass
@@ -75,11 +80,23 @@
         }
     }
 
-    @Test
-    public void test() throws Exception {
-        for (TestCaseContext testCaseCtx : testCaseCollection) {
-            TestsUtils.executeTest(PATH_ACTUAL, testCaseCtx);
+    @Parameters
+    public static Collection<Object[]> tests() throws Exception {
+        Collection<Object[]> testArgs = new ArrayList<Object[]>();
+        TestCaseContext.Builder b = new TestCaseContext.Builder();
+        for (TestCaseContext ctx : b.build(new File(PATH_BASE))) {
+            testArgs.add(new Object[] { ctx });
         }
+        return testArgs;
     }
 
-}
+    public MetadataTest(TestCaseContext tcCtx) {
+        this.tcCtx = tcCtx;
+    }
+
+    @Test
+    public void test() throws Exception {
+        TestsUtils.executeTest(PATH_ACTUAL, tcCtx);
+    }
+
+}
\ No newline at end of file
diff --git a/asterix-app/src/test/java/edu/uci/ics/asterix/test/optimizer/OptimizerTest.java b/asterix-app/src/test/java/edu/uci/ics/asterix/test/optimizer/OptimizerTest.java
index bb66d0d..0f1f8b5 100644
--- a/asterix-app/src/test/java/edu/uci/ics/asterix/test/optimizer/OptimizerTest.java
+++ b/asterix-app/src/test/java/edu/uci/ics/asterix/test/optimizer/OptimizerTest.java
@@ -58,12 +58,12 @@
         System.setProperty(GlobalConfig.WEB_SERVER_PORT_PROPERTY, "19002");
         File outdir = new File(PATH_ACTUAL);
         outdir.mkdirs();
-        
+
         File log = new File("asterix_logs");
         if (log.exists()) {
-            FileUtils.deleteDirectory(log); 
+            FileUtils.deleteDirectory(log);
         }
-        
+
         AsterixHyracksIntegrationUtil.init();
         // Set the node resolver to be the identity resolver that expects node names 
         // to be node controller ids; a valid assumption in test environment. 
@@ -79,10 +79,10 @@
         if (files == null || files.length == 0) {
             outdir.delete();
         }
-        
+
         File log = new File("asterix_logs");
         if (log.exists()) {
-            FileUtils.deleteDirectory(log); 
+            FileUtils.deleteDirectory(log);
         }
     }
 
@@ -138,7 +138,7 @@
             }
             Assume.assumeTrue(!skipped);
 
-            LOGGER.severe("RUN TEST: \"" + queryFile.getPath() + "\"");
+            LOGGER.info("RUN TEST: \"" + queryFile.getPath() + "\"");
             Reader query = new BufferedReader(new InputStreamReader(new FileInputStream(queryFile), "UTF-8"));
             PrintWriter plan = new PrintWriter(actualFile);
             AsterixJavaClient asterix = new AsterixJavaClient(
@@ -180,7 +180,7 @@
                     throw new Exception("Result for " + queryFile + " changed at line " + num + ":\n< \n> "
                             + lineActual);
                 }
-                LOGGER.severe("Test \"" + queryFile.getPath() + "\" PASSED!");
+                LOGGER.info("Test \"" + queryFile.getPath() + "\" PASSED!");
                 actualFile.delete();
             } finally {
                 readerExpected.close();
diff --git a/asterix-app/src/test/java/edu/uci/ics/asterix/test/runtime/ExecutionTest.java b/asterix-app/src/test/java/edu/uci/ics/asterix/test/runtime/ExecutionTest.java
index 6478d0a..2289484 100644
--- a/asterix-app/src/test/java/edu/uci/ics/asterix/test/runtime/ExecutionTest.java
+++ b/asterix-app/src/test/java/edu/uci/ics/asterix/test/runtime/ExecutionTest.java
@@ -1,7 +1,8 @@
 package edu.uci.ics.asterix.test.runtime;
 
 import java.io.File;
-import java.util.List;
+import java.util.ArrayList;
+import java.util.Collection;
 
 import org.apache.commons.io.FileUtils;
 import org.junit.AfterClass;
@@ -9,6 +10,7 @@
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameters;
 
 import edu.uci.ics.asterix.api.common.AsterixHyracksIntegrationUtil;
 import edu.uci.ics.asterix.common.config.GlobalConfig;
@@ -20,71 +22,76 @@
 /**
  * Runs the runtime test cases under 'asterix-app/src/test/resources/runtimets'.
  */
-//@RunWith(Parameterized.class)
+@RunWith(Parameterized.class)
 public class ExecutionTest {
-	private static final String PATH_ACTUAL = "rttest/";
-	private static final String PATH_BASE = "src/test/resources/runtimets/";
+    private static final String PATH_ACTUAL = "rttest/";
+    private static final String PATH_BASE = "src/test/resources/runtimets/";
 
-	private static final String TEST_CONFIG_FILE_NAME = "asterix-build-configuration.xml";
-	private static final String[] ASTERIX_DATA_DIRS = new String[] { "nc1data",
-			"nc2data" };
+    private static final String TEST_CONFIG_FILE_NAME = "asterix-build-configuration.xml";
+    private static final String[] ASTERIX_DATA_DIRS = new String[] { "nc1data", "nc2data" };
 
-	private static List<TestCaseContext> testCaseCollection;
+    @BeforeClass
+    public static void setUp() throws Exception {
+        System.setProperty(GlobalConfig.CONFIG_FILE_PROPERTY, TEST_CONFIG_FILE_NAME);
+        System.setProperty(GlobalConfig.WEB_SERVER_PORT_PROPERTY, "19002");
+        File outdir = new File(PATH_ACTUAL);
+        outdir.mkdirs();
 
-	@BeforeClass
-	public static void setUp() throws Exception {
-		System.setProperty(GlobalConfig.CONFIG_FILE_PROPERTY,
-				TEST_CONFIG_FILE_NAME);
-		System.setProperty(GlobalConfig.WEB_SERVER_PORT_PROPERTY, "19002");
-		File outdir = new File(PATH_ACTUAL);
-		outdir.mkdirs();
+        File log = new File("asterix_logs");
+        if (log.exists()) {
+            FileUtils.deleteDirectory(log);
+        }
 
-		File log = new File("asterix_logs");
-		if (log.exists()) {
-			FileUtils.deleteDirectory(log);
-		}
+        AsterixHyracksIntegrationUtil.init();
 
-		AsterixHyracksIntegrationUtil.init();
+        // TODO: Uncomment when hadoop version is upgraded and adapters are
+        // ported. 
+        HDFSCluster.getInstance().setup();
 
-		// TODO: Uncomment when hadoop version is upgraded and adapters are
-		// ported.
-		HDFSCluster.getInstance().setup();
+        // Set the node resolver to be the identity resolver that expects node names 
+        // to be node controller ids; a valid assumption in test environment. 
+        System.setProperty(FileSystemBasedAdapter.NODE_RESOLVER_FACTORY_PROPERTY,
+                IdentitiyResolverFactory.class.getName());
+    }
 
-		// Set the node resolver to be the identity resolver that expects node
-		// names
-		// to be node controller ids; a valid assumption in test environment.
-		System.setProperty(
-				FileSystemBasedAdapter.NODE_RESOLVER_FACTORY_PROPERTY,
-				IdentitiyResolverFactory.class.getName());
-		TestCaseContext.Builder b = new TestCaseContext.Builder();
-		testCaseCollection = b.build(new File(PATH_BASE));
-	}
+    @AfterClass
+    public static void tearDown() throws Exception {
+        AsterixHyracksIntegrationUtil.deinit();
+        File outdir = new File(PATH_ACTUAL);
+        File[] files = outdir.listFiles();
+        if (files == null || files.length == 0) {
+            outdir.delete();
+        }
+        // clean up the files written by the ASTERIX storage manager
+        for (String d : ASTERIX_DATA_DIRS) {
+            TestsUtils.deleteRec(new File(d));
+        }
 
-	@AfterClass
-	public static void tearDown() throws Exception {
-		AsterixHyracksIntegrationUtil.deinit();
-		File outdir = new File(PATH_ACTUAL);
-		File[] files = outdir.listFiles();
-		if (files == null || files.length == 0) {
-			outdir.delete();
-		}
-		// clean up the files written by the ASTERIX storage manager
-		for (String d : ASTERIX_DATA_DIRS) {
-			TestsUtils.deleteRec(new File(d));
-		}
+        File log = new File("asterix_logs");
+        if (log.exists()) {
+            FileUtils.deleteDirectory(log);
+        }
+        HDFSCluster.getInstance().cleanup();
+    }
 
-		File log = new File("asterix_logs");
-		if (log.exists()) {
-			FileUtils.deleteDirectory(log);
-		}
-		HDFSCluster.getInstance().cleanup();
-	}
+    @Parameters
+    public static Collection<Object[]> tests() throws Exception {
+        Collection<Object[]> testArgs = new ArrayList<Object[]>();
+        TestCaseContext.Builder b = new TestCaseContext.Builder();
+        for (TestCaseContext ctx : b.build(new File(PATH_BASE))) {
+            testArgs.add(new Object[] { ctx });
+        }
+        return testArgs;
+    }
 
-	@Test
-	public void test() throws Exception {
-		for (TestCaseContext testCaseCtx : testCaseCollection) {
-			TestsUtils.executeTest(PATH_ACTUAL, testCaseCtx);
-		}
+    private TestCaseContext tcCtx;
 
-	}
+    public ExecutionTest(TestCaseContext tcCtx) {
+        this.tcCtx = tcCtx;
+    }
+
+    @Test
+    public void test() throws Exception {
+        TestsUtils.executeTest(PATH_ACTUAL, tcCtx);
+    }
 }
diff --git a/asterix-app/src/test/resources/logging.properties b/asterix-app/src/test/resources/logging.properties
index deb88307..6f8cd00 100644
--- a/asterix-app/src/test/resources/logging.properties
+++ b/asterix-app/src/test/resources/logging.properties
@@ -60,6 +60,7 @@
 # For example, set the com.xyz.foo logger to only log SEVERE
 # messages:
 
+edu.uci.ics.asterix.test.level = INFO
 #edu.uci.ics.asterix.level = FINE
 #edu.uci.ics.algebricks.level = FINE
 #edu.uci.ics.hyracks.level = INFO
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-multipred.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-multipred.plan
index 5a5b715..e87dd88 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-multipred.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-multipred.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_01.plan
index c81244a..8315f2b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- HYBRID_HASH_JOIN [$$7][$$10]  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_02.plan
index abbed4a..6269a2b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join-neg_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- HYBRID_HASH_JOIN [$$9][$$8]  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_01.plan
index 0f3828c..c8fd4cb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_02.plan
index c1c1f33..be25081 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_03.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_03.plan
index 2ecd027..f847790 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_04.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_04.plan
index 2bc4b23..8e1be33 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_05.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_05.plan
index fa60146..d3134f2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_05.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-equi-join_05.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_01.plan
index 0f0c06b..66ec32d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_02.plan
index 5cb2903..28645d5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-ge-join_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_01.plan
index 0f0c06b..66ec32d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_02.plan
index 5cb2903..28645d5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-gt-join_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_01.plan
index 0f0c06b..66ec32d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_02.plan
index 5cb2903..28645d5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-le-join_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_01.plan
index 0f0c06b..66ec32d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_02.plan
index 5cb2903..28645d5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/primary-lt-join_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multiindex.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multiindex.plan
index be64ee5..a22212e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multiindex.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multiindex.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multipred.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multipred.plan
index 96632a5..0438a5d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multipred.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join-multipred.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_01.plan
index fac45f2..77aba01 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_02.plan
index fac45f2..77aba01 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_03.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_03.plan
index fac45f2..77aba01 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index-join/secondary-equi-join_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-01.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-01.plan
index 426a99d..3d9e18f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-02.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-02.plan
index 426a99d..3d9e18f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-03.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-03.plan
index 426a99d..3d9e18f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-04.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-04.plan
index 426a99d..3d9e18f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-05.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-05.plan
index 426a99d..3d9e18f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-05.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-05.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-06.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-06.plan
index 426a99d..3d9e18f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-06.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-06.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-07.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-07.plan
index 426a99d..3d9e18f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-07.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-07.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-08.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-08.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-08.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-08.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-09.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-09.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-09.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-09.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-10.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-10.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-10.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-10.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-11.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-11.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-11.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-11.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-12.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-12.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-12.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-12.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-13.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-13.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-13.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-13.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-14.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-14.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-14.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-14.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-15.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-15.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-15.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-15.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-16.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-16.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-16.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-16.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-17.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-17.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-17.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-17.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-18.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-18.plan
index a78e43f..011cf66 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-18.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-18.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-19.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-19.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-19.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-19.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-20.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-20.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-20.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-20.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-21.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-21.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-21.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-21.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-22.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-22.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-22.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-22.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-23.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-23.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-23.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-23.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-24.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-24.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-24.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-24.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-25.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-25.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-25.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-25.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-26.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-26.plan
index 50b1c04..6f13ebb 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-26.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-26.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- BTREE_SEARCH  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-27.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-27.plan
index 40853fa..632a813 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-27.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-27.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-28.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-28.plan
index 5021595..d85d357 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-28.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-28.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-29.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-29.plan
index 5021595..d85d357 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-29.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-29.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-30.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-30.plan
index 5021595..d85d357 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-30.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-primary-30.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-31.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-31.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-31.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-31.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-32.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-32.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-32.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-32.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-33.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-33.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-33.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-33.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-34.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-34.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-34.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-34.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-35.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-35.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-35.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-35.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-36.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-36.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-36.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-36.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-37.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-37.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-37.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-37.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-38.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-38.plan
index 2110116..ef8a923 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-38.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-38.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-39.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-39.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-39.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-39.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-40.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-40.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-40.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-40.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-41.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-41.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-41.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-41.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-42.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-42.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-42.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-42.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-43.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-43.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-43.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-43.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-44.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-44.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-44.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-44.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-45.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-45.plan
index 7087a22..4b4412e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-45.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-45.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-46.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-46.plan
index 7087a22..4b4412e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-46.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-46.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-47.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-47.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-47.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-47.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-48.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-48.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-48.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-48.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-49.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-49.plan
index 7087a22..4b4412e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-49.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-49.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-50.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-50.plan
index 7087a22..4b4412e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-50.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-50.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-51.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-51.plan
index 7087a22..4b4412e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-51.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-51.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-52.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-52.plan
index a48d23a..001e10b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-52.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-52.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-53.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-53.plan
index a48d23a..001e10b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-53.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-53.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-54.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-54.plan
index a48d23a..001e10b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-54.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-54.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-55.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-55.plan
index a48d23a..001e10b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-55.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-55.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-56.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-56.plan
index f18d0ad..e12cdd8 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-56.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-56.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-57.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-57.plan
index f18d0ad..e12cdd8 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-57.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-57.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-58.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-58.plan
index 5b0ae2a..d7667d6 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-58.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-58.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-59.plan b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-59.plan
index 7087a22..4b4412e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-59.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/btree-index/btree-secondary-59.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-complex.plan b/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-complex.plan
index 8d2b4d8..10b5853 100644
--- a/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-complex.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-complex.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-simple.plan b/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-simple.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-simple.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/consolidate-selects-simple.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/count-tweets.plan b/asterix-app/src/test/resources/optimizerts/results/count-tweets.plan
index f24833e..600795f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/count-tweets.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/count-tweets.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/cust_group_no_agg.plan b/asterix-app/src/test/resources/optimizerts/results/cust_group_no_agg.plan
index a1242ff..ab9747f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/cust_group_no_agg.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/cust_group_no_agg.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- SORT_MERGE_EXCHANGE [$$1(ASC) ]  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- PRE_CLUSTERED_GROUP_BY[$$6]  |PARTITIONED|
             {
               -- AGGREGATE  |LOCAL|
diff --git a/asterix-app/src/test/resources/optimizerts/results/denorm-cust-order.plan b/asterix-app/src/test/resources/optimizerts/results/denorm-cust-order.plan
index 80f0a9d..86bafc3 100644
--- a/asterix-app/src/test/resources/optimizerts/results/denorm-cust-order.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/denorm-cust-order.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/fj-phase1.plan b/asterix-app/src/test/resources/optimizerts/results/fj-phase1.plan
index 0b44c4d..494b208 100644
--- a/asterix-app/src/test/resources/optimizerts/results/fj-phase1.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/fj-phase1.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check-panic.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check-panic.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check-panic.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check-panic.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check.plan
index 7aa19a6..d7a4c06 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-check.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-panic.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-panic.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-panic.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance-panic.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance.plan
index 7aa19a6..d7a4c06 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-edit-distance.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-edit-distance.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-edit-distance.plan
index b5ea9d7..021f810 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-edit-distance.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-edit-distance.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-jaccard.plan
index 504d5bf..aec97d2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard-check.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard-check.plan
index f0adce8..2a2ccc4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard-check.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard-check.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard.plan
index f0adce8..2a2ccc4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ngram-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-fuzzyeq-jaccard.plan
index 7aa19a6..d7a4c06 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard-check.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard-check.plan
index 504d5bf..aec97d2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard-check.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard-check.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard.plan
index 504d5bf..aec97d2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/olist-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-fuzzyeq-jaccard.plan
index 7aa19a6..d7a4c06 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard-check.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard-check.plan
index 504d5bf..aec97d2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard-check.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard-check.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard.plan
index 504d5bf..aec97d2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/ulist-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-fuzzyeq-jaccard.plan
index 504d5bf..aec97d2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard-check.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard-check.plan
index f0adce8..2a2ccc4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard-check.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard-check.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard.plan
index f0adce8..2a2ccc4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-basic/word-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_01.plan
index 96697b6..3028f9a 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_02.plan
index 96697b6..3028f9a 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic-nopanic_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- STREAM_SELECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let-panic.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let.plan
index 504d5bf..aec97d2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-edit-distance-check-let.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-let.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-let.plan
index 7ae3ecd..78e761f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-let.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-let.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-multi-let.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-multi-let.plan
index db4c5c5..57730fe 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-multi-let.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ngram-jaccard-check-multi-let.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/olist-jaccard-check-let.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/olist-jaccard-check-let.plan
index f0adce8..2a2ccc4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/olist-jaccard-check-let.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/olist-jaccard-check-let.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ulist-jaccard-check-let.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ulist-jaccard-check-let.plan
index f0adce8..2a2ccc4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ulist-jaccard-check-let.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/ulist-jaccard-check-let.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-let.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-let.plan
index 7ae3ecd..78e761f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-let.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-let.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-multi-let.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-multi-let.plan
index db4c5c5..57730fe 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-multi-let.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-complex/word-jaccard-check-multi-let.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance-inline.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance-inline.plan
index 73ba563..0fab288 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance-inline.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance-inline.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- UNION_ALL  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance.plan
index 37d4f2c..f7d3cb4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-edit-distance.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- UNION_ALL  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-edit-distance.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-edit-distance.plan
index 22cb67b..1be3fb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-edit-distance.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-edit-distance.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- UNION_ALL  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-jaccard.plan
index df958f7..7c74f83 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard-inline.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard-inline.plan
index 50966d0..c5534d6 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard-inline.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard-inline.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard.plan
index 0bb698c..fdbf50f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ngram-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance-inline.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance-inline.plan
index 73ba563..0fab288 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance-inline.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance-inline.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- UNION_ALL  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance.plan
index 37d4f2c..f7d3cb4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-edit-distance.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- UNION_ALL  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-edit-distance.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-edit-distance.plan
index 22cb67b..1be3fb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-edit-distance.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-edit-distance.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- UNION_ALL  |PARTITIONED|
       -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-jaccard.plan
index 294d740..88c4469 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard-inline.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard-inline.plan
index 141fd9d..8b6b08b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard-inline.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard-inline.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard.plan
index a70fe23..ba9879d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/olist-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-fuzzyeq-jaccard.plan
index 294d740..88c4469 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard-inline.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard-inline.plan
index 141fd9d..8b6b08b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard-inline.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard-inline.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard.plan
index a70fe23..ba9879d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/ulist-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-fuzzyeq-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-fuzzyeq-jaccard.plan
index df958f7..7c74f83 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-fuzzyeq-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-fuzzyeq-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard-inline.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard-inline.plan
index 50966d0..c5534d6 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard-inline.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard-inline.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard.plan
index 0bb698c..fdbf50f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join-noeqjoin/word-jaccard.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_01.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_02.plan
index 2181d95..1800e75 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_03.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_04.plan
index dc42118..abd2c39 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_01.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_02.plan
index 2181d95..1800e75 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_03.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_04.plan
index 43dbff9..dffe718 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-edit-distance_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_01.plan
index 25c87b0..65be14f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_02.plan
index 98aa0ef..bfee1a5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_03.plan
index 98aa0ef..bfee1a5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-edit-distance_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_01.plan
index 700ebb7..ab5cf83 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_02.plan
index 69948aa..7877b30 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_03.plan
index 700ebb7..ab5cf83 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-fuzzyeq-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_01.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_02.plan
index d23a6f5..4b767ab 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_03.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_04.plan
index 1d1cd5f..77b00ff 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_01.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_02.plan
index d23a6f5..4b767ab 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_03.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_04.plan
index d1b8f79..32d7e09 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ngram-jaccard_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_01.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_02.plan
index 2181d95..1800e75 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_03.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_04.plan
index dc42118..abd2c39 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_01.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_02.plan
index 2181d95..1800e75 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_03.plan
index 63c5436..a04e378 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_04.plan
index 43dbff9..dffe718 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-edit-distance_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_01.plan
index 98aa0ef..bfee1a5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_02.plan
index 25c87b0..65be14f 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_03.plan
index 98aa0ef..bfee1a5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-edit-distance_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_01.plan
index 4cef1ae..2a4e9de 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_02.plan
index a21a7b5..06826c1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_03.plan
index 4cef1ae..2a4e9de 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-fuzzyeq-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_01.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_02.plan
index 6d8460a..3d0f3f1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_03.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_04.plan
index 4a4430c..156dd43 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_01.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_02.plan
index 6d8460a..3d0f3f1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_03.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_04.plan
index b6a694e..47f5c91 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/olist-jaccard_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_01.plan
index 4cef1ae..2a4e9de 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_02.plan
index a21a7b5..06826c1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_03.plan
index 4cef1ae..2a4e9de 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-fuzzyeq-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_01.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_02.plan
index 6d8460a..3d0f3f1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_03.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_04.plan
index 4a4430c..156dd43 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_01.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_02.plan
index 6d8460a..3d0f3f1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_03.plan
index 44328ef..7c16cef 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_04.plan
index b6a694e..47f5c91 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/ulist-jaccard_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_01.plan
index 700ebb7..ab5cf83 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_02.plan
index 69948aa..7877b30 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_03.plan
index 700ebb7..ab5cf83 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-fuzzyeq-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_01.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_02.plan
index b77169d..0fced26 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_03.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_04.plan
index 1d1cd5f..77b00ff 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_01.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_01.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_02.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_02.plan
index d23a6f5..4b767ab 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_03.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_03.plan
index 901e0f4..3f7ecb1 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_04.plan b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_04.plan
index d1b8f79..32d7e09 100644
--- a/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/inverted-index-join/word-jaccard_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/join-super-key_01.plan b/asterix-app/src/test/resources/optimizerts/results/join-super-key_01.plan
index 011f8be..8149181 100644
--- a/asterix-app/src/test/resources/optimizerts/results/join-super-key_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/join-super-key_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/join-super-key_02.plan b/asterix-app/src/test/resources/optimizerts/results/join-super-key_02.plan
index 591ddbf..92adb3d 100644
--- a/asterix-app/src/test/resources/optimizerts/results/join-super-key_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/join-super-key_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/loj-super-key_01.plan b/asterix-app/src/test/resources/optimizerts/results/loj-super-key_01.plan
index 7dac263..60e9899 100644
--- a/asterix-app/src/test/resources/optimizerts/results/loj-super-key_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/loj-super-key_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/loj-super-key_02.plan b/asterix-app/src/test/resources/optimizerts/results/loj-super-key_02.plan
index 63a3b4e..78159b2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/loj-super-key_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/loj-super-key_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/nested_loj2.plan b/asterix-app/src/test/resources/optimizerts/results/nested_loj2.plan
index f0e1d55..41ae699 100644
--- a/asterix-app/src/test/resources/optimizerts/results/nested_loj2.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/nested_loj2.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/nested_loj3.plan b/asterix-app/src/test/resources/optimizerts/results/nested_loj3.plan
index b68ef76..6d0e32e 100644
--- a/asterix-app/src/test/resources/optimizerts/results/nested_loj3.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/nested_loj3.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/noncollocated.plan b/asterix-app/src/test/resources/optimizerts/results/noncollocated.plan
index f1e1f5d..e92a84c 100644
--- a/asterix-app/src/test/resources/optimizerts/results/noncollocated.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/noncollocated.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/orders-aggreg.plan b/asterix-app/src/test/resources/optimizerts/results/orders-aggreg.plan
index f32df8e..08ad861 100644
--- a/asterix-app/src/test/resources/optimizerts/results/orders-aggreg.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/orders-aggreg.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/orders-composite-index-search.plan b/asterix-app/src/test/resources/optimizerts/results/orders-composite-index-search.plan
index 089064b..39a9eda 100644
--- a/asterix-app/src/test/resources/optimizerts/results/orders-composite-index-search.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/orders-composite-index-search.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/orders-index-search-open.plan b/asterix-app/src/test/resources/optimizerts/results/orders-index-search-open.plan
index 66b693c..b78849b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/orders-index-search-open.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/orders-index-search-open.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/orders-index-search.plan b/asterix-app/src/test/resources/optimizerts/results/orders-index-search.plan
index 66b693c..b78849b 100644
--- a/asterix-app/src/test/resources/optimizerts/results/orders-index-search.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/orders-index-search.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/prim-idx-search-open.plan b/asterix-app/src/test/resources/optimizerts/results/prim-idx-search-open.plan
index e8b196d..2a91fc5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/prim-idx-search-open.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/prim-idx-search-open.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/prim-idx-search.plan b/asterix-app/src/test/resources/optimizerts/results/prim-idx-search.plan
index e8b196d..2a91fc5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/prim-idx-search.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/prim-idx-search.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/pull_select_above_eq_join.plan b/asterix-app/src/test/resources/optimizerts/results/pull_select_above_eq_join.plan
index d50a885..b0d8e64 100644
--- a/asterix-app/src/test/resources/optimizerts/results/pull_select_above_eq_join.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/pull_select_above_eq_join.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/push-project-through-group.plan b/asterix-app/src/test/resources/optimizerts/results/push-project-through-group.plan
index 94273ad..86bcdac 100644
--- a/asterix-app/src/test/resources/optimizerts/results/push-project-through-group.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/push-project-through-group.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/q1.plan b/asterix-app/src/test/resources/optimizerts/results/q1.plan
index 2695827..aa5daa2 100644
--- a/asterix-app/src/test/resources/optimizerts/results/q1.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/q1.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_01.plan b/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_01.plan
index 2f98801..64fdc8c 100644
--- a/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_02.plan b/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_02.plan
index 2f98801..64fdc8c 100644
--- a/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_03.plan b/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_03.plan
index 2f98801..64fdc8c 100644
--- a/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/rtree-index-join/spatial-intersect-point_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index-open.plan b/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index-open.plan
index f7382d8..1845ed7 100644
--- a/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index-open.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index-open.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index.plan b/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index.plan
index f7382d8..1845ed7 100644
--- a/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/rtree-secondary-index.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_PROJECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_01.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_02.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_03.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_04.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_05.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_05.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_05.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_05.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_06.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_06.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_06.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_06.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_07.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_07.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_07.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_07.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_08.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_08.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_08.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-let-to-edit-distance-check_08.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_01.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_02.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_03.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_04.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_05.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_05.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_05.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_05.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_06.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_06.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_06.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_06.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_07.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_07.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_07.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_07.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_08.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_08.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_08.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/edit-distance-to-edit-distance-check_08.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-edit-distance-check.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-edit-distance-check.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-edit-distance-check.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-edit-distance-check.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-jaccard-check.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-jaccard-check.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-jaccard-check.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/fuzzyeq-to-jaccard-check.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_01.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_02.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_03.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_04.plan
index c0e93c8..fcd1fd5 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- STREAM_SELECT  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_05.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_05.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_05.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_05.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_06.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_06.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_06.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_06.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_07.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_07.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_07.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_07.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_08.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_08.plan
index 4d9d3f9..7ec3440 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_08.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-let-to-jaccard-check_08.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ASSIGN  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_01.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_01.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_01.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_01.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_02.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_02.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_02.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_02.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_03.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_03.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_03.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_03.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_04.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_04.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_04.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_04.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_05.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_05.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_05.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_05.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_06.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_06.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_06.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_06.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_07.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_07.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_07.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_07.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_08.plan b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_08.plan
index ae0d5bb..06194e4 100644
--- a/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_08.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/similarity/jaccard-to-jaccard-check_08.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_SELECT  |PARTITIONED|
       -- STREAM_PROJECT  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/optimizerts/results/unnest_list_in_subplan.plan b/asterix-app/src/test/resources/optimizerts/results/unnest_list_in_subplan.plan
index 30a53b3..e9fafd7 100644
--- a/asterix-app/src/test/resources/optimizerts/results/unnest_list_in_subplan.plan
+++ b/asterix-app/src/test/resources/optimizerts/results/unnest_list_in_subplan.plan
@@ -1,5 +1,5 @@
 -- DISTRIBUTE_RESULT  |PARTITIONED|
-  -- RANDOM_MERGE_EXCHANGE  |PARTITIONED|
+  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
     -- STREAM_PROJECT  |PARTITIONED|
       -- ASSIGN  |PARTITIONED|
         -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.1.ddl.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.1.ddl.aql
new file mode 100644
index 0000000..c0bbb1f
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.1.ddl.aql
@@ -0,0 +1,10 @@
+drop dataverse test if exists;
+create dataverse test;
+use dataverse test;
+
+create type Emp as open {
+id:int32,
+name:string ?
+}
+
+create dataset Employee(Emp) primary key id;
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.2.update.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.2.update.aql
new file mode 100644
index 0000000..fa8fb09
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.2.update.aql
@@ -0,0 +1,6 @@
+use dataverse test;
+
+insert into dataset Employee({"id":12,"name":"John Doe"});
+insert into dataset Employee({"id":42});
+insert into dataset Employee({"id":22,"name":"John Smith"});
+insert into dataset Employee({"id":19});
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.3.query.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.3.query.aql
new file mode 100644
index 0000000..8104319
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue395/issue395.3.query.aql
@@ -0,0 +1,4 @@
+use dataverse test;
+
+count(for $l in dataset Employee
+return $l.name)
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.1.ddl.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.1.ddl.aql
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.1.ddl.aql
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.2.update.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.2.update.aql
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.2.update.aql
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.3.query.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.3.query.aql
new file mode 100644
index 0000000..9b0ed8a
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_0/issue412_0.3.query.aql
@@ -0,0 +1,2 @@
+let $l := ["ASTERIX", "Hyracks", null]
+return count($l)
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.1.ddl.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.1.ddl.aql
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.1.ddl.aql
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.2.update.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.2.update.aql
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.2.update.aql
diff --git a/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.3.query.aql b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.3.query.aql
new file mode 100644
index 0000000..f9bc64e
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/aggregate/issue412_1/issue412_1.3.query.aql
@@ -0,0 +1,2 @@
+let $l := [1, 60, null]
+return { "count": count($l), "average": avg($l), "sum": sum($l), "min": min($l), "max": max($l) } 
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/results/aggregate/count_null/count_null.1.adm b/asterix-app/src/test/resources/runtimets/results/aggregate/count_null/count_null.1.adm
index 51d5f4f..df462fe 100644
--- a/asterix-app/src/test/resources/runtimets/results/aggregate/count_null/count_null.1.adm
+++ b/asterix-app/src/test/resources/runtimets/results/aggregate/count_null/count_null.1.adm
@@ -1 +1 @@
-{ "count": null }
\ No newline at end of file
+{ "count": 2 }
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/results/aggregate/issue395/issue395.1.adm b/asterix-app/src/test/resources/runtimets/results/aggregate/issue395/issue395.1.adm
new file mode 100644
index 0000000..bf0d87a
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/results/aggregate/issue395/issue395.1.adm
@@ -0,0 +1 @@
+4
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/results/aggregate/issue412_0/issue412_0.1.adm b/asterix-app/src/test/resources/runtimets/results/aggregate/issue412_0/issue412_0.1.adm
new file mode 100644
index 0000000..e440e5c
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/results/aggregate/issue412_0/issue412_0.1.adm
@@ -0,0 +1 @@
+3
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/results/aggregate/issue412_1/issue412_1.1.adm b/asterix-app/src/test/resources/runtimets/results/aggregate/issue412_1/issue412_1.1.adm
new file mode 100644
index 0000000..7c1107a
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/results/aggregate/issue412_1/issue412_1.1.adm
@@ -0,0 +1 @@
+{ "count": 3, "average": null, "sum": null, "min": null, "max": null }
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/results/aggregate/scalar_count_null/scalar_count_null.1.adm b/asterix-app/src/test/resources/runtimets/results/aggregate/scalar_count_null/scalar_count_null.1.adm
index 1abbc3f..4ff1111 100644
--- a/asterix-app/src/test/resources/runtimets/results/aggregate/scalar_count_null/scalar_count_null.1.adm
+++ b/asterix-app/src/test/resources/runtimets/results/aggregate/scalar_count_null/scalar_count_null.1.adm
@@ -1,7 +1,7 @@
-null
-null
-null
-null
-null
-null
-null
\ No newline at end of file
+4
+4
+4
+4
+4
+4
+4
\ No newline at end of file
diff --git a/asterix-app/src/test/resources/runtimets/results/spatial/create-rtree-index/create-rtree-index.1.adm b/asterix-app/src/test/resources/runtimets/results/spatial/create-rtree-index/create-rtree-index.1.adm
index 6a2a2c6..b9c6dc7 100644
--- a/asterix-app/src/test/resources/runtimets/results/spatial/create-rtree-index/create-rtree-index.1.adm
+++ b/asterix-app/src/test/resources/runtimets/results/spatial/create-rtree-index/create-rtree-index.1.adm
@@ -1,21 +1,21 @@
-1
 2
-3
 4
-5
 6
-7
 8
-9
 10
-11
 12
-13
 14
-15
 16
-17
 18
-19
 20
-21
\ No newline at end of file
+1
+3
+5
+7
+9
+11
+13
+15
+17
+19
+21
diff --git a/asterix-app/src/test/resources/runtimets/testsuite.xml b/asterix-app/src/test/resources/runtimets/testsuite.xml
index 54be5d6..192e171 100644
--- a/asterix-app/src/test/resources/runtimets/testsuite.xml
+++ b/asterix-app/src/test/resources/runtimets/testsuite.xml
@@ -1,6 +1,21 @@
 <test-suite xmlns="urn:xml.testframework.asterix.ics.uci.edu" ResultOffsetPath="results" QueryOffsetPath="queries" QueryFileExtension=".aql">
   <test-group name="aggregate">
     <test-case FilePath="aggregate">
+      <compilation-unit name="issue395">
+        <output-dir compare="Text">issue395</output-dir>
+      </compilation-unit>
+    </test-case>
+    <test-case FilePath="aggregate">
+      <compilation-unit name="issue412_0">
+        <output-dir compare="Text">issue412_0</output-dir>
+      </compilation-unit>
+    </test-case>
+    <test-case FilePath="aggregate">
+      <compilation-unit name="issue412_1">
+        <output-dir compare="Text">issue412_1</output-dir>
+      </compilation-unit>
+    </test-case>
+    <test-case FilePath="aggregate">
       <compilation-unit name="avg_double">
         <output-dir compare="Text">avg_double</output-dir>
       </compilation-unit>
@@ -97,6 +112,9 @@
       </compilation-unit>
     </test-case>
     -->
+    <!-- TODO(madhusudancs): These tests that test for local_<agg>/global_<agg> functions should be removed, but
+    before that we should modify the code to make sure those built-in functions are still defined but not exposed
+    by AQL, so leaving these test cases commented.
     <test-case FilePath="aggregate">
       <compilation-unit name="global-avg_01">
         <output-dir compare="Text">global-avg_01</output-dir>
@@ -167,6 +185,7 @@
         <output-dir compare="Text">local-avg_int8_null</output-dir>
       </compilation-unit>
     </test-case>
+    -->
     <test-case FilePath="aggregate">
       <compilation-unit name="max_empty_01">
         <output-dir compare="Text">max_empty_01</output-dir>
@@ -4192,4 +4211,4 @@
       </compilation-unit>
     </test-case>
   </test-group>
-</test-suite>
\ No newline at end of file
+</test-suite>
diff --git a/asterix-common/src/main/java/edu/uci/ics/asterix/common/config/AsterixProperties.java b/asterix-common/src/main/java/edu/uci/ics/asterix/common/config/AsterixProperties.java
index 20a0d11..04e974d 100644
--- a/asterix-common/src/main/java/edu/uci/ics/asterix/common/config/AsterixProperties.java
+++ b/asterix-common/src/main/java/edu/uci/ics/asterix/common/config/AsterixProperties.java
@@ -247,6 +247,6 @@
             default:
                 level = Level.ALL;
         }
-        Logger.getLogger("edu.uci.ics").setLevel(level);
+        Logger.getLogger(".").setLevel(level);
     }
 }
diff --git a/asterix-common/src/test/java/edu/uci/ics/asterix/test/aql/TestsUtils.java b/asterix-common/src/test/java/edu/uci/ics/asterix/test/aql/TestsUtils.java
index 7e9b08f..8449971 100644
--- a/asterix-common/src/test/java/edu/uci/ics/asterix/test/aql/TestsUtils.java
+++ b/asterix-common/src/test/java/edu/uci/ics/asterix/test/aql/TestsUtils.java
@@ -31,398 +31,369 @@
 import edu.uci.ics.asterix.testframework.context.TestCaseContext;
 import edu.uci.ics.asterix.testframework.context.TestFileContext;
 import edu.uci.ics.asterix.testframework.xml.TestCase.CompilationUnit;
-import edu.uci.ics.hyracks.algebricks.common.exceptions.NotImplementedException;
 
 public class TestsUtils {
 
-	private static final String EXTENSION_AQL_RESULT = "adm";
-	private static final Logger LOGGER = Logger.getLogger(TestsUtils.class
-			.getName());
-	private static Method managixExecuteMethod = null;
+    private static final String EXTENSION_AQL_RESULT = "adm";
+    private static final Logger LOGGER = Logger.getLogger(TestsUtils.class.getName());
+    private static Method managixExecuteMethod = null;
 
-	/**
-	 * Probably does not work well with symlinks.
-	 */
-	public static boolean deleteRec(File path) {
-		if (path.isDirectory()) {
-			for (File f : path.listFiles()) {
-				if (!deleteRec(f)) {
-					return false;
-				}
-			}
-		}
-		return path.delete();
-	}
+    /**
+     * Probably does not work well with symlinks.
+     */
+    public static boolean deleteRec(File path) {
+        if (path.isDirectory()) {
+            for (File f : path.listFiles()) {
+                if (!deleteRec(f)) {
+                    return false;
+                }
+            }
+        }
+        return path.delete();
+    }
 
-	public static void runScriptAndCompareWithResult(File scriptFile,
-			PrintWriter print, File expectedFile, File actualFile)
-			throws Exception {
-		BufferedReader readerExpected = new BufferedReader(
-				new InputStreamReader(new FileInputStream(expectedFile),
-						"UTF-8"));
-		BufferedReader readerActual = new BufferedReader(new InputStreamReader(
-				new FileInputStream(actualFile), "UTF-8"));
-		String lineExpected, lineActual;
-		int num = 1;
-		try {
-			while ((lineExpected = readerExpected.readLine()) != null) {
-				lineActual = readerActual.readLine();
-				// Assert.assertEquals(lineExpected, lineActual);
-				if (lineActual == null) {
-					if (lineExpected.isEmpty()) {
-						continue;
-					}
-					throw new Exception("Result for " + scriptFile
-							+ " changed at line " + num + ":\n< "
-							+ lineExpected + "\n> ");
-				}
+    public static void runScriptAndCompareWithResult(File scriptFile, PrintWriter print, File expectedFile,
+            File actualFile) throws Exception {
+        BufferedReader readerExpected = new BufferedReader(new InputStreamReader(new FileInputStream(expectedFile),
+                "UTF-8"));
+        BufferedReader readerActual = new BufferedReader(
+                new InputStreamReader(new FileInputStream(actualFile), "UTF-8"));
+        String lineExpected, lineActual;
+        int num = 1;
+        try {
+            while ((lineExpected = readerExpected.readLine()) != null) {
+                lineActual = readerActual.readLine();
+                // Assert.assertEquals(lineExpected, lineActual);
+                if (lineActual == null) {
+                    if (lineExpected.isEmpty()) {
+                        continue;
+                    }
+                    throw new Exception("Result for " + scriptFile + " changed at line " + num + ":\n< " + lineExpected
+                            + "\n> ");
+                }
 
-				if (!equalStrings(lineExpected.split("Timestamp")[0],
-						lineActual.split("Timestamp")[0])) {
-					fail("Result for " + scriptFile + " changed at line " + num
-							+ ":\n< " + lineExpected + "\n> " + lineActual);
-				}
+                if (!equalStrings(lineExpected.split("Timestamp")[0], lineActual.split("Timestamp")[0])) {
+                    fail("Result for " + scriptFile + " changed at line " + num + ":\n< " + lineExpected + "\n> "
+                            + lineActual);
+                }
 
-				++num;
-			}
-			lineActual = readerActual.readLine();
-			// Assert.assertEquals(null, lineActual);
-			if (lineActual != null) {
-				throw new Exception("Result for " + scriptFile
-						+ " changed at line " + num + ":\n< \n> " + lineActual);
-			}
-			// actualFile.delete();
-		} finally {
-			readerExpected.close();
-			readerActual.close();
-		}
+                ++num;
+            }
+            lineActual = readerActual.readLine();
+            // Assert.assertEquals(null, lineActual);
+            if (lineActual != null) {
+                throw new Exception("Result for " + scriptFile + " changed at line " + num + ":\n< \n> " + lineActual);
+            }
+            // actualFile.delete();
+        } finally {
+            readerExpected.close();
+            readerActual.close();
+        }
 
-	}
+    }
 
-	private static boolean equalStrings(String s1, String s2) {
-		String[] rowsOne = s1.split("\n");
-		String[] rowsTwo = s2.split("\n");
+    private static boolean equalStrings(String s1, String s2) {
+        String[] rowsOne = s1.split("\n");
+        String[] rowsTwo = s2.split("\n");
 
-		for (int i = 0; i < rowsOne.length; i++) {
-			String row1 = rowsOne[i];
-			String row2 = rowsTwo[i];
+        for (int i = 0; i < rowsOne.length; i++) {
+            String row1 = rowsOne[i];
+            String row2 = rowsTwo[i];
 
-			if (row1.equals(row2))
-				continue;
+            if (row1.equals(row2))
+                continue;
 
-			String[] fields1 = row1.split(" ");
-			String[] fields2 = row2.split(" ");
+            String[] fields1 = row1.split(" ");
+            String[] fields2 = row2.split(" ");
 
-			for (int j = 0; j < fields1.length; j++) {
-				if (fields1[j].equals(fields2[j])) {
-					continue;
-				} else if (fields1[j].indexOf('.') < 0) {
-					return false;
-				} else {
-					fields1[j] = fields1[j].split(",")[0];
-					fields2[j] = fields2[j].split(",")[0];
-					Double double1 = Double.parseDouble(fields1[j]);
-					Double double2 = Double.parseDouble(fields2[j]);
-					float float1 = (float) double1.doubleValue();
-					float float2 = (float) double2.doubleValue();
+            for (int j = 0; j < fields1.length; j++) {
+                if (fields1[j].equals(fields2[j])) {
+                    continue;
+                } else if (fields1[j].indexOf('.') < 0) {
+                    return false;
+                } else {
+                    fields1[j] = fields1[j].split(",")[0];
+                    fields2[j] = fields2[j].split(",")[0];
+                    Double double1 = Double.parseDouble(fields1[j]);
+                    Double double2 = Double.parseDouble(fields2[j]);
+                    float float1 = (float) double1.doubleValue();
+                    float float2 = (float) double2.doubleValue();
 
-					if (Math.abs(float1 - float2) == 0)
-						continue;
-					else {
-						return false;
-					}
-				}
-			}
-		}
-		return true;
-	}
+                    if (Math.abs(float1 - float2) == 0)
+                        continue;
+                    else {
+                        return false;
+                    }
+                }
+            }
+        }
+        return true;
+    }
 
-	public static String aqlExtToResExt(String fname) {
-		int dot = fname.lastIndexOf('.');
-		return fname.substring(0, dot + 1) + EXTENSION_AQL_RESULT;
-	}
+    public static String aqlExtToResExt(String fname) {
+        int dot = fname.lastIndexOf('.');
+        return fname.substring(0, dot + 1) + EXTENSION_AQL_RESULT;
+    }
 
-	public static void writeResultsToFile(File actualFile, JSONObject result)
-			throws IOException, JSONException {
-		BufferedWriter writer = new BufferedWriter(new FileWriter(actualFile));
-		Results res = new Results(result);
-		for (String line : res) {
-			writer.write(line);
-			writer.newLine();
-		}
-		writer.close();
-	}
+    public static void writeResultsToFile(File actualFile, JSONObject result) throws IOException, JSONException {
+        BufferedWriter writer = new BufferedWriter(new FileWriter(actualFile));
+        Results res = new Results(result);
+        for (String line : res) {
+            writer.write(line);
+            writer.newLine();
+        }
+        writer.close();
+    }
 
-	public static class Results implements Iterable<String> {
-		private final JSONArray chunks;
+    public static class Results implements Iterable<String> {
+        private final JSONArray chunks;
 
-		public Results(JSONObject result) throws JSONException {
-			chunks = result.getJSONArray("results");
-		}
+        public Results(JSONObject result) throws JSONException {
+            chunks = result.getJSONArray("results");
+        }
 
-		public Iterator<String> iterator() {
-			return new ResultIterator(chunks);
-		}
-	}
+        public Iterator<String> iterator() {
+            return new ResultIterator(chunks);
+        }
+    }
 
-	public static class ResultIterator implements Iterator<String> {
-		private final JSONArray chunks;
+    public static class ResultIterator implements Iterator<String> {
+        private final JSONArray chunks;
 
-		private int chunkCounter = 0;
-		private int recordCounter = 0;
+        private int chunkCounter = 0;
+        private int recordCounter = 0;
 
-		public ResultIterator(JSONArray chunks) {
-			this.chunks = chunks;
-		}
+        public ResultIterator(JSONArray chunks) {
+            this.chunks = chunks;
+        }
 
-		@Override
-		public boolean hasNext() {
-			JSONArray resultArray;
-			try {
-				resultArray = chunks.getJSONArray(chunkCounter);
-				if (resultArray.getString(recordCounter) != null) {
-					return true;
-				}
-			} catch (JSONException e) {
-				return false;
-			}
-			return false;
-		}
+        @Override
+        public boolean hasNext() {
+            JSONArray resultArray;
+            try {
+                resultArray = chunks.getJSONArray(chunkCounter);
+                if (resultArray.getString(recordCounter) != null) {
+                    return true;
+                }
+            } catch (JSONException e) {
+                return false;
+            }
+            return false;
+        }
 
-		@Override
-		public String next() throws NoSuchElementException {
-			JSONArray resultArray;
-			String item = "";
+        @Override
+        public String next() throws NoSuchElementException {
+            JSONArray resultArray;
+            String item = "";
 
-			try {
-				resultArray = chunks.getJSONArray(chunkCounter);
-				item = resultArray.getString(recordCounter);
-				if (item == null) {
-					throw new NoSuchElementException();
-				}
-				item = item.trim();
+            try {
+                resultArray = chunks.getJSONArray(chunkCounter);
+                item = resultArray.getString(recordCounter);
+                if (item == null) {
+                    throw new NoSuchElementException();
+                }
+                item = item.trim();
 
-				recordCounter++;
-				if (recordCounter >= resultArray.length()) {
-					chunkCounter++;
-					recordCounter = 0;
-				}
-			} catch (JSONException e) {
-				throw new NoSuchElementException(e.getMessage());
-			}
-			return item;
-		}
+                recordCounter++;
+                if (recordCounter >= resultArray.length()) {
+                    chunkCounter++;
+                    recordCounter = 0;
+                }
+            } catch (JSONException e) {
+                throw new NoSuchElementException(e.getMessage());
+            }
+            return item;
+        }
 
-		@Override
-		public void remove() {
-			throw new NotImplementedException();
-		}
-	}
+        @Override
+        public void remove() {
+            throw new UnsupportedOperationException();
+        }
+    }
 
-	// Executes Query and returns results as JSONArray
-	public static JSONObject executeQuery(String str) throws Exception {
+    // Executes Query and returns results as JSONArray
+    public static JSONObject executeQuery(String str) throws Exception {
 
-		final String url = "http://localhost:19101/query";
+        final String url = "http://localhost:19101/query";
 
-		// Create an instance of HttpClient.
-		HttpClient client = new HttpClient();
+        // Create an instance of HttpClient.
+        HttpClient client = new HttpClient();
 
-		// Create a method instance.
-		GetMethod method = new GetMethod(url);
+        // Create a method instance.
+        GetMethod method = new GetMethod(url);
 
-		method.setQueryString(new NameValuePair[] { new NameValuePair("query",
-				str) });
+        method.setQueryString(new NameValuePair[] { new NameValuePair("query", str) });
 
-		// Provide custom retry handler is necessary
-		method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,
-				new DefaultHttpMethodRetryHandler(3, false));
+        // Provide custom retry handler is necessary
+        method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler(3, false));
 
-		JSONObject result = null;
+        JSONObject result = null;
 
-		try {
-			// Execute the method.
-			int statusCode = client.executeMethod(method);
+        try {
+            // Execute the method.
+            int statusCode = client.executeMethod(method);
 
-			// Check if the method was executed successfully.
-			if (statusCode != HttpStatus.SC_OK) {
-				System.err.println("Method failed: " + method.getStatusLine());
-			}
+            // Check if the method was executed successfully.
+            if (statusCode != HttpStatus.SC_OK) {
+                System.err.println("Method failed: " + method.getStatusLine());
+            }
 
-			// Read the response body as String.
-			String responseBody = method.getResponseBodyAsString();
+            // Read the response body as String.
+            String responseBody = method.getResponseBodyAsString();
 
-			result = new JSONObject(responseBody);
-		} catch (Exception e) {
-			System.out.println(e.getMessage());
-			e.printStackTrace();
-		}
-		return result;
-	}
+            result = new JSONObject(responseBody);
+        } catch (Exception e) {
+            System.out.println(e.getMessage());
+            e.printStackTrace();
+        }
+        return result;
+    }
 
-	// To execute Update statements
-	// Insert and Delete statements are executed here
-	public static void executeUpdate(String str) throws Exception {
-		final String url = "http://localhost:19101/update";
+    // To execute Update statements
+    // Insert and Delete statements are executed here
+    public static void executeUpdate(String str) throws Exception {
+        final String url = "http://localhost:19101/update";
 
-		// Create an instance of HttpClient.
-		HttpClient client = new HttpClient();
+        // Create an instance of HttpClient.
+        HttpClient client = new HttpClient();
 
-		// Create a method instance.
-		GetMethod method = new GetMethod(url);
+        // Create a method instance.
+        GetMethod method = new GetMethod(url);
 
-		method.setQueryString(new NameValuePair[] { new NameValuePair(
-				"statements", str) });
+        method.setQueryString(new NameValuePair[] { new NameValuePair("statements", str) });
 
-		// Provide custom retry handler is necessary
-		method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,
-				new DefaultHttpMethodRetryHandler(3, false));
+        // Provide custom retry handler is necessary
+        method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler(3, false));
 
-		// Execute the method.
-		int statusCode = client.executeMethod(method);
+        // Execute the method.
+        int statusCode = client.executeMethod(method);
 
-		// Check if the method was executed successfully.
-		if (statusCode != HttpStatus.SC_OK) {
-			System.err.println("Method failed: " + method.getStatusLine());
-		}
-	}
+        // Check if the method was executed successfully.
+        if (statusCode != HttpStatus.SC_OK) {
+            System.err.println("Method failed: " + method.getStatusLine());
+        }
+    }
 
-	// To execute DDL and Update statements
-	// create type statement
-	// create dataset statement
-	// create index statement
-	// create dataverse statement
-	// create function statement
-	public static void executeDDL(String str) throws Exception {
-		final String url = "http://localhost:19101/ddl";
+    // To execute DDL and Update statements
+    // create type statement
+    // create dataset statement
+    // create index statement
+    // create dataverse statement
+    // create function statement
+    public static void executeDDL(String str) throws Exception {
+        final String url = "http://localhost:19101/ddl";
 
-		// Create an instance of HttpClient.
-		HttpClient client = new HttpClient();
+        // Create an instance of HttpClient.
+        HttpClient client = new HttpClient();
 
-		// Create a method instance.
-		GetMethod method = new GetMethod(url);
+        // Create a method instance.
+        GetMethod method = new GetMethod(url);
 
-		method.setQueryString(new NameValuePair[] { new NameValuePair("ddl",
-				str) });
+        method.setQueryString(new NameValuePair[] { new NameValuePair("ddl", str) });
 
-		// Provide custom retry handler is necessary
-		method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,
-				new DefaultHttpMethodRetryHandler(3, false));
+        // Provide custom retry handler is necessary
+        method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler(3, false));
 
-		// Execute the method.
-		int statusCode = client.executeMethod(method);
+        // Execute the method.
+        int statusCode = client.executeMethod(method);
 
-		// Check if the method was executed successfully.
-		if (statusCode != HttpStatus.SC_OK) {
-			System.err.println("Method failed: " + method.getStatusLine());
-		}
-	}
+        // Check if the method was executed successfully.
+        if (statusCode != HttpStatus.SC_OK) {
+            System.err.println("Method failed: " + method.getStatusLine());
+        }
+    }
 
-	// Method that reads a DDL/Update/Query File
-	// and returns the contents as a string
-	// This string is later passed to REST API for execution.
-	public static String readTestFile(File testFile) throws Exception {
-		BufferedReader reader = new BufferedReader(new FileReader(testFile));
-		String line = null;
-		StringBuilder stringBuilder = new StringBuilder();
-		String ls = System.getProperty("line.separator");
+    // Method that reads a DDL/Update/Query File
+    // and returns the contents as a string
+    // This string is later passed to REST API for execution.
+    public static String readTestFile(File testFile) throws Exception {
+        BufferedReader reader = new BufferedReader(new FileReader(testFile));
+        String line = null;
+        StringBuilder stringBuilder = new StringBuilder();
+        String ls = System.getProperty("line.separator");
 
-		while ((line = reader.readLine()) != null) {
-			stringBuilder.append(line);
-			stringBuilder.append(ls);
-		}
+        while ((line = reader.readLine()) != null) {
+            stringBuilder.append(line);
+            stringBuilder.append(ls);
+        }
 
-		return stringBuilder.toString();
-	}
+        return stringBuilder.toString();
+    }
 
-	public static void executeManagixCommand(String command)
-			throws ClassNotFoundException, NoSuchMethodException,
-			SecurityException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
-		if (managixExecuteMethod == null) {
-			Class clazz = Class
-					.forName("edu.uci.ics.asterix.installer.test.AsterixInstallerIntegrationUtil");
-			managixExecuteMethod = clazz.getMethod("executeCommand",
-					String.class);
-		}
-		managixExecuteMethod.invoke(null, command);
-	}
+    public static void executeManagixCommand(String command) throws ClassNotFoundException, NoSuchMethodException,
+            SecurityException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
+        if (managixExecuteMethod == null) {
+            Class clazz = Class.forName("edu.uci.ics.asterix.installer.test.AsterixInstallerIntegrationUtil");
+            managixExecuteMethod = clazz.getMethod("executeCommand", String.class);
+        }
+        managixExecuteMethod.invoke(null, command);
+    }
 
-	public static void executeTest(String actualPath,
-			TestCaseContext testCaseCtx) throws Exception {
+    public static void executeTest(String actualPath, TestCaseContext testCaseCtx) throws Exception {
 
-		File testFile;
-		File expectedResultFile;
-		String statement;
-		List<TestFileContext> expectedResultFileCtxs;
-		List<TestFileContext> testFileCtxs;
+        File testFile;
+        File expectedResultFile;
+        String statement;
+        List<TestFileContext> expectedResultFileCtxs;
+        List<TestFileContext> testFileCtxs;
 
-		int queryCount = 0;
-		JSONObject result;
+        int queryCount = 0;
+        JSONObject result;
 
-		List<CompilationUnit> cUnits = testCaseCtx.getTestCase()
-				.getCompilationUnit();
-		for (CompilationUnit cUnit : cUnits) {
-			LOGGER.info("[TEST]: " + testCaseCtx.getTestCase().getFilePath()
-					+ "/" + cUnit.getName());
+        List<CompilationUnit> cUnits = testCaseCtx.getTestCase().getCompilationUnit();
+        for (CompilationUnit cUnit : cUnits) {
+            LOGGER.info("[TEST]: " + testCaseCtx.getTestCase().getFilePath() + "/" + cUnit.getName());
 
-			testFileCtxs = testCaseCtx.getTestFiles(cUnit);
-			expectedResultFileCtxs = testCaseCtx.getExpectedResultFiles(cUnit);
+            testFileCtxs = testCaseCtx.getTestFiles(cUnit);
+            expectedResultFileCtxs = testCaseCtx.getExpectedResultFiles(cUnit);
 
-			for (TestFileContext ctx : testFileCtxs) {
-				testFile = ctx.getFile();
-				statement = TestsUtils.readTestFile(testFile);
-				try {
-					switch (ctx.getType()) {
-					case "ddl":
-						TestsUtils.executeDDL(statement);
-						break;
-					case "update":
-						TestsUtils.executeUpdate(statement);
-						break;
-					case "query":
-						result = TestsUtils.executeQuery(statement);
-						if (!cUnit.getExpectedError().isEmpty()) {
-							if (!result.has("error")) {
-								throw new Exception("Test \"" + testFile
-										+ "\" FAILED!");
-							}
-						} else {
-							expectedResultFile = expectedResultFileCtxs.get(
-									queryCount).getFile();
+            for (TestFileContext ctx : testFileCtxs) {
+                testFile = ctx.getFile();
+                statement = TestsUtils.readTestFile(testFile);
+                try {
+                    switch (ctx.getType()) {
+                        case "ddl":
+                            TestsUtils.executeDDL(statement);
+                            break;
+                        case "update":
+                            TestsUtils.executeUpdate(statement);
+                            break;
+                        case "query":
+                            result = TestsUtils.executeQuery(statement);
+                            if (!cUnit.getExpectedError().isEmpty()) {
+                                if (!result.has("error")) {
+                                    throw new Exception("Test \"" + testFile + "\" FAILED!");
+                                }
+                            } else {
+                                expectedResultFile = expectedResultFileCtxs.get(queryCount).getFile();
 
-							File actualFile = new File(actualPath
-									+ File.separator
-									+ testCaseCtx.getTestCase().getFilePath()
-											.replace(File.separator, "_") + "_"
-									+ cUnit.getName() + ".adm");
+                                File actualFile = new File(actualPath + File.separator
+                                        + testCaseCtx.getTestCase().getFilePath().replace(File.separator, "_") + "_"
+                                        + cUnit.getName() + ".adm");
 
-							File actualResultFile = testCaseCtx
-									.getActualResultFile(cUnit, new File(
-											actualPath));
-							actualResultFile.getParentFile().mkdirs();
+                                File actualResultFile = testCaseCtx.getActualResultFile(cUnit, new File(actualPath));
+                                actualResultFile.getParentFile().mkdirs();
 
-							TestsUtils.writeResultsToFile(actualFile, result);
+                                TestsUtils.writeResultsToFile(actualFile, result);
 
-							TestsUtils.runScriptAndCompareWithResult(testFile,
-									new PrintWriter(System.err),
-									expectedResultFile, actualFile);
-						}
-						queryCount++;
-						break;
-					case "mgx":
-						executeManagixCommand(statement);
-						break;
-					default:
-						throw new IllegalArgumentException(
-								"No statements of type " + ctx.getType());
-					}
-				} catch (Exception e) {
-					if (cUnit.getExpectedError().isEmpty()) {
-						throw new Exception(
-								"Test \"" + testFile + "\" FAILED!", e);
-					}
-				}
-			}
-		}
+                                TestsUtils.runScriptAndCompareWithResult(testFile, new PrintWriter(System.err),
+                                        expectedResultFile, actualFile);
+                            }
+                            queryCount++;
+                            break;
+                        case "mgx":
+                            executeManagixCommand(statement);
+                            break;
+                        default:
+                            throw new IllegalArgumentException("No statements of type " + ctx.getType());
+                    }
+                } catch (Exception e) {
+                    if (cUnit.getExpectedError().isEmpty()) {
+                        throw new Exception("Test \"" + testFile + "\" FAILED!", e);
+                    }
+                }
+            }
+        }
 
-	}
+    }
 }
diff --git a/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/AqlMetadataProvider.java b/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/AqlMetadataProvider.java
index 5e759b1..8bbddec 100644
--- a/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/AqlMetadataProvider.java
+++ b/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/AqlMetadataProvider.java
@@ -643,7 +643,6 @@
         ResultSetDataSink rsds = (ResultSetDataSink) sink;
         ResultSetSinkId rssId = (ResultSetSinkId) rsds.getId();
         ResultSetId rsId = rssId.getResultSetId();
-        String nodeName = rssId.getResultNodeName();
 
         ResultWriterOperatorDescriptor resultWriter = null;
         try {
@@ -654,8 +653,7 @@
             throw new AlgebricksException(e);
         }
 
-        AlgebricksPartitionConstraint apc = new AlgebricksAbsolutePartitionConstraint(new String[] { nodeName });
-        return new Pair<IOperatorDescriptor, AlgebricksPartitionConstraint>(resultWriter, apc);
+        return new Pair<IOperatorDescriptor, AlgebricksPartitionConstraint>(resultWriter, null);
     }
 
     @Override
diff --git a/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetDataSink.java b/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetDataSink.java
index 53513d2..ad91111 100644
--- a/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetDataSink.java
+++ b/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetDataSink.java
@@ -17,6 +17,8 @@
 
 import edu.uci.ics.hyracks.algebricks.core.algebra.metadata.IDataSink;
 import edu.uci.ics.hyracks.algebricks.core.algebra.properties.IPartitioningProperty;
+import edu.uci.ics.hyracks.algebricks.core.algebra.properties.RandomPartitioningProperty;
+import edu.uci.ics.hyracks.algebricks.core.algebra.properties.ResultSetDomain;
 
 public class ResultSetDataSink implements IDataSink {
 
@@ -40,7 +42,6 @@
 
     @Override
     public IPartitioningProperty getPartitioningProperty() {
-        return IPartitioningProperty.UNPARTITIONED;
+        return new RandomPartitioningProperty(new ResultSetDomain());
     }
-
 }
diff --git a/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetSinkId.java b/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetSinkId.java
index fc5152f..1eb4336 100644
--- a/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetSinkId.java
+++ b/asterix-metadata/src/main/java/edu/uci/ics/asterix/metadata/declared/ResultSetSinkId.java
@@ -20,23 +20,16 @@
 
     private final ResultSetId resultSetId;
 
-    private final String resultNodeName;
-
-    public ResultSetSinkId(ResultSetId resultSetId, String resultNodeName) {
+    public ResultSetSinkId(ResultSetId resultSetId) {
         this.resultSetId = resultSetId;
-        this.resultNodeName = resultNodeName;
     }
 
     @Override
     public String toString() {
-        return "ResultSetId: " + resultSetId + "@" + resultNodeName;
+        return "ResultSetId: " + resultSetId;
     }
 
     public ResultSetId getResultSetId() {
         return resultSetId;
     }
-
-    public String getResultNodeName() {
-        return resultNodeName;
-    }
 }
diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/om/typecomputer/impl/ScalarVersionOfAggregateResultType.java b/asterix-om/src/main/java/edu/uci/ics/asterix/om/typecomputer/impl/ScalarVersionOfAggregateResultType.java
index c8ba938..9126065 100644
--- a/asterix-om/src/main/java/edu/uci/ics/asterix/om/typecomputer/impl/ScalarVersionOfAggregateResultType.java
+++ b/asterix-om/src/main/java/edu/uci/ics/asterix/om/typecomputer/impl/ScalarVersionOfAggregateResultType.java
@@ -1,6 +1,5 @@
 package edu.uci.ics.asterix.om.typecomputer.impl;
 
-
 import edu.uci.ics.asterix.om.typecomputer.base.IResultTypeComputer;
 import edu.uci.ics.asterix.om.types.ATypeTag;
 import edu.uci.ics.asterix.om.types.AUnionType;
diff --git a/asterix-runtime/src/main/java/edu/uci/ics/asterix/runtime/aggregates/std/CountAggregateFunction.java b/asterix-runtime/src/main/java/edu/uci/ics/asterix/runtime/aggregates/std/CountAggregateFunction.java
index e4d015b..82c1e8a 100644
--- a/asterix-runtime/src/main/java/edu/uci/ics/asterix/runtime/aggregates/std/CountAggregateFunction.java
+++ b/asterix-runtime/src/main/java/edu/uci/ics/asterix/runtime/aggregates/std/CountAggregateFunction.java
@@ -6,7 +6,6 @@
 import edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider;
 import edu.uci.ics.asterix.om.base.AInt32;
 import edu.uci.ics.asterix.om.base.AMutableInt32;
-import edu.uci.ics.asterix.om.base.ANull;
 import edu.uci.ics.asterix.om.types.ATypeTag;
 import edu.uci.ics.asterix.om.types.BuiltinType;
 import edu.uci.ics.asterix.om.types.EnumDeserializer;
@@ -20,19 +19,15 @@
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.IFrameTupleReference;
 
 /**
- * count(NULL) returns NULL.
+ * COUNT returns the number of items in the given list. Note that COUNT(NULL) is not allowed.
  */
 public class CountAggregateFunction implements ICopyAggregateFunction {
     private AMutableInt32 result = new AMutableInt32(-1);
     @SuppressWarnings("unchecked")
     private ISerializerDeserializer<AInt32> int32Serde = AqlSerializerDeserializerProvider.INSTANCE
             .getSerializerDeserializer(BuiltinType.AINT32);
-    @SuppressWarnings("unchecked")
-    private ISerializerDeserializer<ANull> nullSerde = AqlSerializerDeserializerProvider.INSTANCE
-            .getSerializerDeserializer(BuiltinType.ANULL);
     private ArrayBackedValueStorage inputVal = new ArrayBackedValueStorage();
     private ICopyEvaluator eval;
-    private boolean metNull;
     private int cnt;
     private DataOutput out;
 
@@ -44,7 +39,6 @@
     @Override
     public void init() {
         cnt = 0;
-        metNull = false;
     }
 
     @Override
@@ -53,9 +47,7 @@
         eval.evaluate(tuple);
         ATypeTag typeTag = EnumDeserializer.ATYPETAGDESERIALIZER.deserialize(inputVal.getByteArray()[0]);
         // Ignore SYSTEM_NULL.
-        if (typeTag == ATypeTag.NULL) {
-            metNull = true;
-        } else {
+        if (typeTag != ATypeTag.SYSTEM_NULL) {
             cnt++;
         }
     }
@@ -63,12 +55,8 @@
     @Override
     public void finish() throws AlgebricksException {
         try {
-            if (metNull) {
-                nullSerde.serialize(ANull.NULL, out);
-            } else {
-                result.setValue(cnt);
-                int32Serde.serialize(result, out);
-            }
+            result.setValue(cnt);
+            int32Serde.serialize(result, out);
         } catch (IOException e) {
             throw new AlgebricksException(e);
         }