diff --git a/core/src/main/java/org/opensearch/sql/analysis/Analyzer.java b/core/src/main/java/org/opensearch/sql/analysis/Analyzer.java
index 9f78b245942..f4b9abe8330 100644
--- a/core/src/main/java/org/opensearch/sql/analysis/Analyzer.java
+++ b/core/src/main/java/org/opensearch/sql/analysis/Analyzer.java
@@ -380,8 +380,7 @@ public LogicalPlan visitRareTopN(RareTopN node, AnalysisContext context) {
     fields.forEach(
         field -> newEnv.define(new Symbol(Namespace.FIELD_NAME, field.toString()), field.type()));
 
-    List<Argument> options = node.getArguments();
-    Integer noOfResults = (Integer) options.get(0).getValue().getValue();
+    Integer noOfResults = node.getNoOfResults();
 
     return new LogicalRareTopN(child, node.getCommandType(), noOfResults, fields, groupBys);
   }
diff --git a/core/src/main/java/org/opensearch/sql/ast/dsl/AstDSL.java b/core/src/main/java/org/opensearch/sql/ast/dsl/AstDSL.java
index 86b2343ace1..67cc893c5b0 100644
--- a/core/src/main/java/org/opensearch/sql/ast/dsl/AstDSL.java
+++ b/core/src/main/java/org/opensearch/sql/ast/dsl/AstDSL.java
@@ -540,8 +540,16 @@ public static RareTopN rareTopN(
       List<Argument> noOfResults,
       List<UnresolvedExpression> groupList,
       Field... fields) {
-    return new RareTopN(input, commandType, noOfResults, Arrays.asList(fields), groupList)
-        .attach(input);
+    Integer N =
+        (Integer)
+            Argument.ArgumentMap.of(noOfResults)
+                .getOrDefault("noOfResults", new Literal(10, DataType.INTEGER))
+                .getValue();
+    List<Argument> removed =
+        noOfResults.stream()
+            .filter(argument -> !argument.getArgName().equals("noOfResults"))
+            .toList();
+    return new RareTopN(commandType, N, removed, Arrays.asList(fields), groupList).attach(input);
   }
 
   public static Limit limit(UnresolvedPlan input, Integer limit, Integer offset) {
diff --git a/core/src/main/java/org/opensearch/sql/ast/expression/Argument.java b/core/src/main/java/org/opensearch/sql/ast/expression/Argument.java
index 0e0e032e22b..607e27b7de9 100644
--- a/core/src/main/java/org/opensearch/sql/ast/expression/Argument.java
+++ b/core/src/main/java/org/opensearch/sql/ast/expression/Argument.java
@@ -37,6 +37,8 @@ public <R, C> R accept(AbstractNodeVisitor<R, C> nodeVisitor, C context) {
   }
 
   /** ArgumentMap is a helper class to get argument value by name. */
+  @EqualsAndHashCode
+  @ToString
   public static class ArgumentMap {
     private final Map<String, Literal> map;
 
diff --git a/core/src/main/java/org/opensearch/sql/ast/tree/RareTopN.java b/core/src/main/java/org/opensearch/sql/ast/tree/RareTopN.java
index 3fd3aa3a2c0..6c543ddc8c3 100644
--- a/core/src/main/java/org/opensearch/sql/ast/tree/RareTopN.java
+++ b/core/src/main/java/org/opensearch/sql/ast/tree/RareTopN.java
@@ -7,7 +7,6 @@
 
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import lombok.AllArgsConstructor;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
@@ -24,12 +23,11 @@
 @ToString
 @EqualsAndHashCode(callSuper = false)
 @RequiredArgsConstructor
-@AllArgsConstructor
 public class RareTopN extends UnresolvedPlan {
 
   private UnresolvedPlan child;
   private final CommandType commandType;
-  // arguments: noOfResults: Integer, countField: String, showCount: Boolean
+  private final Integer noOfResults;
   private final List<Argument> arguments;
   private final List<Field> fields;
   private final List<UnresolvedExpression> groupExprList;
@@ -54,4 +52,10 @@ public enum CommandType {
     TOP,
     RARE
   }
+
+  public enum Option {
+    countField,
+    showCount,
+    useNull,
+  }
 }
diff --git a/core/src/main/java/org/opensearch/sql/calcite/CalciteRelNodeVisitor.java b/core/src/main/java/org/opensearch/sql/calcite/CalciteRelNodeVisitor.java
index 2c90f059986..67151519274 100644
--- a/core/src/main/java/org/opensearch/sql/calcite/CalciteRelNodeVisitor.java
+++ b/core/src/main/java/org/opensearch/sql/calcite/CalciteRelNodeVisitor.java
@@ -15,9 +15,9 @@
 import static org.opensearch.sql.ast.tree.Sort.SortOrder.ASC;
 import static org.opensearch.sql.ast.tree.Sort.SortOrder.DESC;
 import static org.opensearch.sql.calcite.utils.PlanUtils.ROW_NUMBER_COLUMN_FOR_DEDUP;
-import static org.opensearch.sql.calcite.utils.PlanUtils.ROW_NUMBER_COLUMN_NAME;
 import static org.opensearch.sql.calcite.utils.PlanUtils.ROW_NUMBER_COLUMN_NAME_MAIN;
 import static org.opensearch.sql.calcite.utils.PlanUtils.ROW_NUMBER_COLUMN_NAME_SUBSEARCH;
+import static org.opensearch.sql.calcite.utils.PlanUtils.ROW_NUMBER_COLUMN_NAME_TOP_RARE;
 import static org.opensearch.sql.calcite.utils.PlanUtils.getRelation;
 import static org.opensearch.sql.calcite.utils.PlanUtils.getRexCall;
 import static org.opensearch.sql.calcite.utils.PlanUtils.transformPlanToAttachChild;
@@ -1128,22 +1128,7 @@ public RelNode visitAggregation(Aggregation node, CalcitePlanContext context) {
     Pair<List<RexNode>, List<AggCall>> aggregationAttributes =
         aggregateWithTrimming(groupExprList, aggExprList, context);
     if (toAddHintsOnAggregate) {
-      final RelHint statHits =
-          RelHint.builder("stats_args").hintOption(Argument.BUCKET_NULLABLE, "false").build();
-      assert context.relBuilder.peek() instanceof LogicalAggregate
-          : "Stats hits should be added to LogicalAggregate";
-      context.relBuilder.hints(statHits);
-      context
-          .relBuilder
-          .getCluster()
-          .setHintStrategies(
-              HintStrategyTable.builder()
-                  .hintStrategy(
-                      "stats_args",
-                      (hint, rel) -> {
-                        return rel instanceof LogicalAggregate;
-                      })
-                  .build());
+      addIgnoreNullBucketHintToAggregate(context);
     }
 
     // schema reordering
@@ -1862,9 +1847,8 @@ public RelNode visitKmeans(Kmeans node, CalcitePlanContext context) {
   @Override
   public RelNode visitRareTopN(RareTopN node, CalcitePlanContext context) {
     visitChildren(node, context);
-
-    ArgumentMap arguments = ArgumentMap.of(node.getArguments());
-    String countFieldName = (String) arguments.get("countField").getValue();
+    ArgumentMap argumentMap = ArgumentMap.of(node.getArguments());
+    String countFieldName = (String) argumentMap.get(RareTopN.Option.countField.name()).getValue();
     if (context.relBuilder.peek().getRowType().getFieldNames().contains(countFieldName)) {
       throw new IllegalArgumentException(
           "Field `"
@@ -1879,8 +1863,27 @@ public RelNode visitRareTopN(RareTopN node, CalcitePlanContext context) {
     groupExprList.addAll(fieldList);
     List<UnresolvedExpression> aggExprList =
         List.of(AstDSL.alias(countFieldName, AstDSL.aggregate("count", null)));
+
+    // if usenull=false, add a isNotNull before Aggregate and the hint to this Aggregate
+    Boolean bucketNullable = (Boolean) argumentMap.get(RareTopN.Option.useNull.name()).getValue();
+    boolean toAddHintsOnAggregate = false;
+    if (!bucketNullable && !groupExprList.isEmpty()) {
+      toAddHintsOnAggregate = true;
+      // add isNotNull filter before aggregation to filter out null bucket
+      List<RexNode> groupByList =
+          groupExprList.stream().map(expr -> rexVisitor.analyze(expr, context)).toList();
+      context.relBuilder.filter(
+          PlanUtils.getSelectColumns(groupByList).stream()
+              .map(context.relBuilder::field)
+              .map(context.relBuilder::isNotNull)
+              .toList());
+    }
     aggregateWithTrimming(groupExprList, aggExprList, context);
 
+    if (toAddHintsOnAggregate) {
+      addIgnoreNullBucketHintToAggregate(context);
+    }
+
     // 2. add a window column
     List<RexNode> partitionKeys = rexVisitor.analyze(node.getGroupExprList(), context);
     RexNode countField;
@@ -1899,26 +1902,46 @@ public RelNode visitRareTopN(RareTopN node, CalcitePlanContext context) {
             List.of(countField),
             WindowFrame.toCurrentRow());
     context.relBuilder.projectPlus(
-        context.relBuilder.alias(rowNumberWindowOver, ROW_NUMBER_COLUMN_NAME));
+        context.relBuilder.alias(rowNumberWindowOver, ROW_NUMBER_COLUMN_NAME_TOP_RARE));
 
     // 3. filter row_number() <= k in each partition
-    Integer N = (Integer) arguments.get("noOfResults").getValue();
+    int k = node.getNoOfResults();
     context.relBuilder.filter(
         context.relBuilder.lessThanOrEqual(
-            context.relBuilder.field(ROW_NUMBER_COLUMN_NAME), context.relBuilder.literal(N)));
+            context.relBuilder.field(ROW_NUMBER_COLUMN_NAME_TOP_RARE),
+            context.relBuilder.literal(k)));
 
     // 4. project final output. the default output is group by list + field list
-    Boolean showCount = (Boolean) arguments.get("showCount").getValue();
+    Boolean showCount = (Boolean) argumentMap.get(RareTopN.Option.showCount.name()).getValue();
     if (showCount) {
-      context.relBuilder.projectExcept(context.relBuilder.field(ROW_NUMBER_COLUMN_NAME));
+      context.relBuilder.projectExcept(context.relBuilder.field(ROW_NUMBER_COLUMN_NAME_TOP_RARE));
     } else {
       context.relBuilder.projectExcept(
-          context.relBuilder.field(ROW_NUMBER_COLUMN_NAME),
+          context.relBuilder.field(ROW_NUMBER_COLUMN_NAME_TOP_RARE),
           context.relBuilder.field(countFieldName));
     }
     return context.relBuilder.peek();
   }
 
+  private static void addIgnoreNullBucketHintToAggregate(CalcitePlanContext context) {
+    final RelHint statHits =
+        RelHint.builder("stats_args").hintOption(Argument.BUCKET_NULLABLE, "false").build();
+    assert context.relBuilder.peek() instanceof LogicalAggregate
+        : "Stats hits should be added to LogicalAggregate";
+    context.relBuilder.hints(statHits);
+    context
+        .relBuilder
+        .getCluster()
+        .setHintStrategies(
+            HintStrategyTable.builder()
+                .hintStrategy(
+                    "stats_args",
+                    (hint, rel) -> {
+                      return rel instanceof LogicalAggregate;
+                    })
+                .build());
+  }
+
   @Override
   public RelNode visitTableFunction(TableFunction node, CalcitePlanContext context) {
     throw new CalciteUnsupportedException("Table function is unsupported in Calcite");
diff --git a/core/src/main/java/org/opensearch/sql/calcite/utils/PlanUtils.java b/core/src/main/java/org/opensearch/sql/calcite/utils/PlanUtils.java
index 153135c5cf8..3e7b97ea1a6 100644
--- a/core/src/main/java/org/opensearch/sql/calcite/utils/PlanUtils.java
+++ b/core/src/main/java/org/opensearch/sql/calcite/utils/PlanUtils.java
@@ -62,7 +62,7 @@ public interface PlanUtils {
   /** this is only for dedup command, do not reuse it in other command */
   String ROW_NUMBER_COLUMN_FOR_DEDUP = "_row_number_dedup_";
 
-  String ROW_NUMBER_COLUMN_NAME = "_row_number_";
+  String ROW_NUMBER_COLUMN_NAME_TOP_RARE = "_row_number_top_rare_";
   String ROW_NUMBER_COLUMN_NAME_MAIN = "_row_number_main_";
   String ROW_NUMBER_COLUMN_NAME_SUBSEARCH = "_row_number_subsearch_";
 
diff --git a/docs/user/ppl/admin/settings.rst b/docs/user/ppl/admin/settings.rst
index 88db0a59bd2..d99cdc6c2d0 100644
--- a/docs/user/ppl/admin/settings.rst
+++ b/docs/user/ppl/admin/settings.rst
@@ -211,6 +211,7 @@ The behaviours it controlled includes:
 
 - The default value of argument ``bucket_nullable`` in ``stats`` command. Check `stats command <../cmd/stats.rst>`_ for details.
 - The return value of ``divide`` and ``/`` operator. Check `expressions <../functions/expressions.rst>`_ for details.
+- The default value of argument ``usenull`` in ``top`` and ``rare`` commands. Check `top command <../cmd/top.rst>`_  and `rare command <../cmd/rare.rst>`_ for details.
 
 Example 1
 -------
diff --git a/docs/user/ppl/cmd/rare.rst b/docs/user/ppl/cmd/rare.rst
index 8d2011cc1b2..d16dc4878dd 100644
--- a/docs/user/ppl/cmd/rare.rst
+++ b/docs/user/ppl/cmd/rare.rst
@@ -1,6 +1,6 @@
-=============
+====
 rare
-=============
+====
 
 .. rubric:: Table of contents
 
@@ -10,13 +10,13 @@ rare
 
 
 Description
-============
+===========
 | Using ``rare`` command to find the least common tuple of values of all fields in the field list.
 
 **Note**: A maximum of 10 results is returned for each distinct tuple of values of the group-by fields.
 
 Syntax
-============
+======
 rare <field-list> [by-clause]
 
 rare [rare-options] <field-list> [by-clause] ``(available from 3.1.0+)``
@@ -26,10 +26,13 @@ rare [rare-options] <field-list> [by-clause] ``(available from 3.1.0+)``
 * rare-options: optional. options for the rare command. Supported syntax is [countfield=<string>] [showcount=<bool>].
 * showcount=<bool>: optional. whether to create a field in output that represent a count of the tuple of values. Default value is ``true``.
 * countfield=<string>: optional. the name of the field that contains count. Default value is ``'count'``.
+* usenull=<bool>: optional (since 3.4.0). whether to output the null value. The default value of ``usenull`` is determined by ``plugins.ppl.syntax.legacy.preferred``:
 
+ * When ``plugins.ppl.syntax.legacy.preferred=true``, ``usenull`` defaults to ``true``
+ * When ``plugins.ppl.syntax.legacy.preferred=false``, ``usenull`` defaults to ``false``
 
 Example 1: Find the least common values in a field
-===========================================
+==================================================
 
 The example finds least common gender of all the accounts.
 
@@ -46,7 +49,7 @@ PPL query::
 
 
 Example 2: Find the least common values organized by gender
-====================================================
+===========================================================
 
 The example finds least common age of all the accounts group by gender.
 
@@ -66,12 +69,10 @@ PPL query::
 Example 3: Rare command with Calcite enabled
 ============================================
 
-The example finds least common gender of all the accounts when ``plugins.calcite.enabled`` is true.
-
 PPL query::
 
-    PPL> source=accounts | rare gender;
-    fetched row
+    os> source=accounts | rare gender;
+    fetched rows / total rows = 2/2
     +--------+-------+
     | gender | count |
     |--------+-------|
@@ -83,12 +84,10 @@ PPL query::
 Example 4: Specify the count field option
 =========================================
 
-The example specifies the count field when ``plugins.calcite.enabled`` is true.
-
 PPL query::
 
-    PPL> source=accounts | rare countfield='cnt' gender;
-    fetched row
+    os> source=accounts | rare countfield='cnt' gender;
+    fetched rows / total rows = 2/2
     +--------+-----+
     | gender | cnt |
     |--------+-----|
@@ -96,6 +95,36 @@ PPL query::
     | M      | 3   |
     +--------+-----+
 
+
+Example 5: Specify the usenull field option
+===========================================
+
+PPL query::
+
+    os> source=accounts | rare usenull=false email;
+    fetched rows / total rows = 3/3
+    +-----------------------+-------+
+    | email                 | count |
+    |-----------------------+-------|
+    | amberduke@pyrami.com  | 1     |
+    | daleadams@boink.com   | 1     |
+    | hattiebond@netagy.com | 1     |
+    +-----------------------+-------+
+
+PPL query::
+
+    os> source=accounts | rare usenull=true email;
+    fetched rows / total rows = 4/4
+    +-----------------------+-------+
+    | email                 | count |
+    |-----------------------+-------|
+    | null                  | 1     |
+    | amberduke@pyrami.com  | 1     |
+    | daleadams@boink.com   | 1     |
+    | hattiebond@netagy.com | 1     |
+    +-----------------------+-------+
+
+
 Limitations
 ===========
 The ``rare`` command is not rewritten to OpenSearch DSL, it is only executed on the coordination node.
diff --git a/docs/user/ppl/cmd/top.rst b/docs/user/ppl/cmd/top.rst
index 5f4bfb9b4b6..a786d7ed9a9 100644
--- a/docs/user/ppl/cmd/top.rst
+++ b/docs/user/ppl/cmd/top.rst
@@ -1,6 +1,6 @@
-=============
+===
 top
-=============
+===
 
 .. rubric:: Table of contents
 
@@ -10,12 +10,12 @@ top
 
 
 Description
-============
+===========
 | Using ``top`` command to find the most common tuple of values of all fields in the field list.
 
 
 Syntax
-============
+======
 top [N] <field-list> [by-clause]
 
 top [N] [top-options] <field-list> [by-clause] ``(available from 3.1.0+)``
@@ -26,10 +26,13 @@ top [N] [top-options] <field-list> [by-clause] ``(available from 3.1.0+)``
 * top-options: optional. options for the top command. Supported syntax is [countfield=<string>] [showcount=<bool>].
 * showcount=<bool>: optional. whether to create a field in output that represent a count of the tuple of values. Default value is ``true``.
 * countfield=<string>: optional. the name of the field that contains count. Default value is ``'count'``.
+* usenull=<bool>: optional (since 3.4.0). whether to output the null value. The default value of ``usenull`` is determined by ``plugins.ppl.syntax.legacy.preferred``:
 
+ * When ``plugins.ppl.syntax.legacy.preferred=true``, ``usenull`` defaults to ``true``
+ * When ``plugins.ppl.syntax.legacy.preferred=false``, ``usenull`` defaults to ``false``
 
 Example 1: Find the most common values in a field
-===========================================
+=================================================
 
 The example finds most common gender of all the accounts.
 
@@ -45,7 +48,7 @@ PPL query::
     +--------+
 
 Example 2: Find the most common values in a field
-===========================================
+=================================================
 
 The example finds most common gender of all the accounts.
 
@@ -60,7 +63,7 @@ PPL query::
     +--------+
 
 Example 2: Find the most common values organized by gender
-====================================================
+==========================================================
 
 The example finds most common age of all the accounts group by gender.
 
@@ -78,12 +81,10 @@ PPL query::
 Example 3: Top command with Calcite enabled
 ===========================================
 
-The example finds most common gender of all the accounts when ``plugins.calcite.enabled`` is true.
-
 PPL query::
 
-    PPL> source=accounts | top gender;
-    fetched row
+    os> source=accounts | top gender;
+    fetched rows / total rows = 2/2
     +--------+-------+
     | gender | count |
     |--------+-------|
@@ -95,12 +96,10 @@ PPL query::
 Example 4: Specify the count field option
 =========================================
 
-The example specifies the count field when ``plugins.calcite.enabled`` is true.
-
 PPL query::
 
-    PPL> source=accounts | top countfield='cnt' gender;
-    fetched row
+    os> source=accounts | top countfield='cnt' gender;
+    fetched rows / total rows = 2/2
     +--------+-----+
     | gender | cnt |
     |--------+-----|
@@ -108,6 +107,36 @@ PPL query::
     | F      | 1   |
     +--------+-----+
 
+
+Example 5: Specify the usenull field option
+===========================================
+
+PPL query::
+
+    os> source=accounts | top usenull=false email;
+    fetched rows / total rows = 3/3
+    +-----------------------+-------+
+    | email                 | count |
+    |-----------------------+-------|
+    | amberduke@pyrami.com  | 1     |
+    | daleadams@boink.com   | 1     |
+    | hattiebond@netagy.com | 1     |
+    +-----------------------+-------+
+
+PPL query::
+
+    os> source=accounts | top usenull=true email;
+    fetched rows / total rows = 4/4
+    +-----------------------+-------+
+    | email                 | count |
+    |-----------------------+-------|
+    | null                  | 1     |
+    | amberduke@pyrami.com  | 1     |
+    | daleadams@boink.com   | 1     |
+    | hattiebond@netagy.com | 1     |
+    +-----------------------+-------+
+
+
 Limitations
 ===========
 The ``top`` command is not rewritten to OpenSearch DSL, it is only executed on the coordination node.
diff --git a/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteExplainIT.java b/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteExplainIT.java
index 81936ffbfb1..d874b09bdd6 100644
--- a/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteExplainIT.java
+++ b/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteExplainIT.java
@@ -22,6 +22,7 @@
 import org.junit.Assume;
 import org.junit.Ignore;
 import org.junit.Test;
+import org.opensearch.sql.common.setting.Settings;
 import org.opensearch.sql.ppl.ExplainIT;
 
 public class CalciteExplainIT extends ExplainIT {
@@ -1266,6 +1267,60 @@ public void testReplaceCommandExplain() throws IOException {
                 TEST_INDEX_ACCOUNT)));
   }
 
+  @Test
+  public void testExplainRareCommandUseNull() throws IOException {
+    String expected = loadExpectedPlan("explain_rare_usenull_false.yaml");
+    assertYamlEqualsIgnoreId(
+        expected,
+        explainQueryYaml(
+            String.format("source=%s | rare 2 usenull=false state by gender", TEST_INDEX_ACCOUNT)));
+    expected = loadExpectedPlan("explain_rare_usenull_true.yaml");
+    assertYamlEqualsIgnoreId(
+        expected,
+        explainQueryYaml(
+            String.format("source=%s | rare 2 usenull=true state by gender", TEST_INDEX_ACCOUNT)));
+    withSettings(
+        Settings.Key.PPL_SYNTAX_LEGACY_PREFERRED,
+        "false",
+        () -> {
+          try {
+            assertYamlEqualsIgnoreId(
+                loadExpectedPlan("explain_rare_usenull_false.yaml"),
+                explainQueryYaml(
+                    String.format("source=%s | rare 2 state by gender", TEST_INDEX_ACCOUNT)));
+          } catch (IOException e) {
+            throw new RuntimeException(e);
+          }
+        });
+  }
+
+  @Test
+  public void testExplainTopCommandUseNull() throws IOException {
+    String expected = loadExpectedPlan("explain_top_usenull_false.yaml");
+    assertYamlEqualsIgnoreId(
+        expected,
+        explainQueryYaml(
+            String.format("source=%s | top 2 usenull=false state by gender", TEST_INDEX_ACCOUNT)));
+    expected = loadExpectedPlan("explain_top_usenull_true.yaml");
+    assertYamlEqualsIgnoreId(
+        expected,
+        explainQueryYaml(
+            String.format("source=%s | top 2 usenull=true state by gender", TEST_INDEX_ACCOUNT)));
+    withSettings(
+        Settings.Key.PPL_SYNTAX_LEGACY_PREFERRED,
+        "false",
+        () -> {
+          try {
+            assertYamlEqualsIgnoreId(
+                loadExpectedPlan("explain_top_usenull_false.yaml"),
+                explainQueryYaml(
+                    String.format("source=%s | top 2 state by gender", TEST_INDEX_ACCOUNT)));
+          } catch (IOException e) {
+            throw new RuntimeException(e);
+          }
+        });
+  }
+
   // Test cases for verifying the fix of https://github.com/opensearch-project/sql/issues/4571
   @Test
   public void testPushDownMinOrMaxAggOnDerivedField() throws IOException {
diff --git a/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteRareCommandIT.java b/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteRareCommandIT.java
index eaf59e09a73..9689b7385bb 100644
--- a/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteRareCommandIT.java
+++ b/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteRareCommandIT.java
@@ -5,6 +5,15 @@
 
 package org.opensearch.sql.calcite.remote;
 
+import static org.opensearch.sql.legacy.TestsConstants.TEST_INDEX_BANK_WITH_NULL_VALUES;
+import static org.opensearch.sql.util.MatcherUtils.schema;
+import static org.opensearch.sql.util.MatcherUtils.verifyNumOfRows;
+import static org.opensearch.sql.util.MatcherUtils.verifySchemaInOrder;
+
+import java.io.IOException;
+import org.json.JSONObject;
+import org.junit.Test;
+import org.opensearch.sql.common.setting.Settings;
 import org.opensearch.sql.ppl.RareCommandIT;
 
 public class CalciteRareCommandIT extends RareCommandIT {
@@ -12,5 +21,42 @@ public class CalciteRareCommandIT extends RareCommandIT {
   public void init() throws Exception {
     super.init();
     enableCalcite();
+    loadIndex(Index.BANK_WITH_NULL_VALUES);
+  }
+
+  @Test
+  public void testRareCommandUseNull() throws IOException {
+    JSONObject result =
+        executeQuery(String.format("source=%s | rare age", TEST_INDEX_BANK_WITH_NULL_VALUES));
+    verifySchemaInOrder(result, schema("age", "int"), schema("count", "bigint"));
+    verifyNumOfRows(result, 6);
+  }
+
+  @Test
+  public void testRareCommandUseNullFalse() throws IOException {
+    JSONObject result =
+        executeQuery(
+            String.format("source=%s | rare usenull=false age", TEST_INDEX_BANK_WITH_NULL_VALUES));
+    verifySchemaInOrder(result, schema("age", "int"), schema("count", "bigint"));
+    verifyNumOfRows(result, 5);
+  }
+
+  @Test
+  public void testRareCommandLegacyFalse() throws IOException {
+    withSettings(
+        Settings.Key.PPL_SYNTAX_LEGACY_PREFERRED,
+        "false",
+        () -> {
+          JSONObject result;
+          try {
+            result =
+                executeQuery(
+                    String.format("source=%s | rare age", TEST_INDEX_BANK_WITH_NULL_VALUES));
+          } catch (IOException e) {
+            throw new RuntimeException(e);
+          }
+          verifySchemaInOrder(result, schema("age", "int"), schema("count", "bigint"));
+          verifyNumOfRows(result, 5);
+        });
   }
 }
diff --git a/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteTopCommandIT.java b/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteTopCommandIT.java
index 76a8b1e49cf..e555576a9cd 100644
--- a/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteTopCommandIT.java
+++ b/integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteTopCommandIT.java
@@ -5,6 +5,15 @@
 
 package org.opensearch.sql.calcite.remote;
 
+import static org.opensearch.sql.legacy.TestsConstants.TEST_INDEX_BANK_WITH_NULL_VALUES;
+import static org.opensearch.sql.util.MatcherUtils.schema;
+import static org.opensearch.sql.util.MatcherUtils.verifyNumOfRows;
+import static org.opensearch.sql.util.MatcherUtils.verifySchemaInOrder;
+
+import java.io.IOException;
+import org.json.JSONObject;
+import org.junit.Test;
+import org.opensearch.sql.common.setting.Settings;
 import org.opensearch.sql.ppl.TopCommandIT;
 
 public class CalciteTopCommandIT extends TopCommandIT {
@@ -12,5 +21,42 @@ public class CalciteTopCommandIT extends TopCommandIT {
   public void init() throws Exception {
     super.init();
     enableCalcite();
+    loadIndex(Index.BANK_WITH_NULL_VALUES);
+  }
+
+  @Test
+  public void testTopCommandUseNull() throws IOException {
+    JSONObject result =
+        executeQuery(String.format("source=%s | top age", TEST_INDEX_BANK_WITH_NULL_VALUES));
+    verifySchemaInOrder(result, schema("age", "int"), schema("count", "bigint"));
+    verifyNumOfRows(result, 6);
+  }
+
+  @Test
+  public void testTopCommandUseNullFalse() throws IOException {
+    JSONObject result =
+        executeQuery(
+            String.format("source=%s | top usenull=false age", TEST_INDEX_BANK_WITH_NULL_VALUES));
+    verifySchemaInOrder(result, schema("age", "int"), schema("count", "bigint"));
+    verifyNumOfRows(result, 5);
+  }
+
+  @Test
+  public void testTopCommandLegacyFalse() throws IOException {
+    withSettings(
+        Settings.Key.PPL_SYNTAX_LEGACY_PREFERRED,
+        "false",
+        () -> {
+          JSONObject result;
+          try {
+            result =
+                executeQuery(
+                    String.format("source=%s | top age", TEST_INDEX_BANK_WITH_NULL_VALUES));
+          } catch (IOException e) {
+            throw new RuntimeException(e);
+          }
+          verifySchemaInOrder(result, schema("age", "int"), schema("count", "bigint"));
+          verifyNumOfRows(result, 5);
+        });
   }
 }
diff --git a/integ-test/src/test/resources/expectedOutput/calcite/explain_rare_usenull_false.yaml b/integ-test/src/test/resources/expectedOutput/calcite/explain_rare_usenull_false.yaml
new file mode 100644
index 00000000000..4557813e9a2
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite/explain_rare_usenull_false.yaml
@@ -0,0 +1,15 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                LogicalFilter(condition=[AND(IS NOT NULL($4), IS NOT NULL($7))])
+                  CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]], PushDownContext=[[AGGREGATION->rel#:LogicalAggregate.NONE.[](input=RelSubset#,group={0, 1},count=COUNT())], OpenSearchRequestBuilder(sourceBuilder={"from":0,"size":0,"timeout":"1m","aggregations":{"composite_buckets":{"composite":{"size":1000,"sources":[{"gender":{"terms":{"field":"gender.keyword","missing_bucket":false,"order":"asc"}}},{"state":{"terms":{"field":"state.keyword","missing_bucket":false,"order":"asc"}}}]}}}}, requestedTotalSize=2147483647, pageSize=null, startFrom=0)])
\ No newline at end of file
diff --git a/integ-test/src/test/resources/expectedOutput/calcite/explain_rare_usenull_true.yaml b/integ-test/src/test/resources/expectedOutput/calcite/explain_rare_usenull_true.yaml
new file mode 100644
index 00000000000..58900d698fd
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite/explain_rare_usenull_true.yaml
@@ -0,0 +1,14 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]], PushDownContext=[[AGGREGATION->rel#:LogicalAggregate.NONE.[](input=RelSubset#,group={0, 1},count=COUNT())], OpenSearchRequestBuilder(sourceBuilder={"from":0,"size":0,"timeout":"1m","aggregations":{"composite_buckets":{"composite":{"size":1000,"sources":[{"gender":{"terms":{"field":"gender.keyword","missing_bucket":true,"missing_order":"first","order":"asc"}}},{"state":{"terms":{"field":"state.keyword","missing_bucket":true,"missing_order":"first","order":"asc"}}}]}}}}, requestedTotalSize=2147483647, pageSize=null, startFrom=0)])
\ No newline at end of file
diff --git a/integ-test/src/test/resources/expectedOutput/calcite/explain_top_usenull_false.yaml b/integ-test/src/test/resources/expectedOutput/calcite/explain_top_usenull_false.yaml
new file mode 100644
index 00000000000..cf2820f4097
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite/explain_top_usenull_false.yaml
@@ -0,0 +1,15 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                LogicalFilter(condition=[AND(IS NOT NULL($4), IS NOT NULL($7))])
+                  CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2 DESC] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]], PushDownContext=[[AGGREGATION->rel#:LogicalAggregate.NONE.[](input=RelSubset#,group={0, 1},count=COUNT())], OpenSearchRequestBuilder(sourceBuilder={"from":0,"size":0,"timeout":"1m","aggregations":{"composite_buckets":{"composite":{"size":1000,"sources":[{"gender":{"terms":{"field":"gender.keyword","missing_bucket":false,"order":"asc"}}},{"state":{"terms":{"field":"state.keyword","missing_bucket":false,"order":"asc"}}}]}}}}, requestedTotalSize=2147483647, pageSize=null, startFrom=0)])
\ No newline at end of file
diff --git a/integ-test/src/test/resources/expectedOutput/calcite/explain_top_usenull_true.yaml b/integ-test/src/test/resources/expectedOutput/calcite/explain_top_usenull_true.yaml
new file mode 100644
index 00000000000..a12cb33592b
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite/explain_top_usenull_true.yaml
@@ -0,0 +1,14 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2 DESC] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]], PushDownContext=[[AGGREGATION->rel#:LogicalAggregate.NONE.[](input=RelSubset#,group={0, 1},count=COUNT())], OpenSearchRequestBuilder(sourceBuilder={"from":0,"size":0,"timeout":"1m","aggregations":{"composite_buckets":{"composite":{"size":1000,"sources":[{"gender":{"terms":{"field":"gender.keyword","missing_bucket":true,"missing_order":"first","order":"asc"}}},{"state":{"terms":{"field":"state.keyword","missing_bucket":true,"missing_order":"first","order":"asc"}}}]}}}}, requestedTotalSize=2147483647, pageSize=null, startFrom=0)])
\ No newline at end of file
diff --git a/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_rare_usenull_false.yaml b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_rare_usenull_false.yaml
new file mode 100644
index 00000000000..5ef75ad3f69
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_rare_usenull_false.yaml
@@ -0,0 +1,17 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                LogicalFilter(condition=[AND(IS NOT NULL($4), IS NOT NULL($7))])
+                  CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          EnumerableAggregate(group=[{4, 7}], count=[COUNT()])
+            EnumerableCalc(expr#0..16=[{inputs}], expr#17=[IS NOT NULL($t4)], expr#18=[IS NOT NULL($t7)], expr#19=[AND($t17, $t18)], proj#0..16=[{exprs}], $condition=[$t19])
+              CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
\ No newline at end of file
diff --git a/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_rare_usenull_true.yaml b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_rare_usenull_true.yaml
new file mode 100644
index 00000000000..3b24078b2b5
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_rare_usenull_true.yaml
@@ -0,0 +1,15 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          EnumerableAggregate(group=[{4, 7}], count=[COUNT()])
+            CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
\ No newline at end of file
diff --git a/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_top_usenull_false.yaml b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_top_usenull_false.yaml
new file mode 100644
index 00000000000..352f9851897
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_top_usenull_false.yaml
@@ -0,0 +1,17 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                LogicalFilter(condition=[AND(IS NOT NULL($4), IS NOT NULL($7))])
+                  CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2 DESC] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          EnumerableAggregate(group=[{4, 7}], count=[COUNT()])
+            EnumerableCalc(expr#0..16=[{inputs}], expr#17=[IS NOT NULL($t4)], expr#18=[IS NOT NULL($t7)], expr#19=[AND($t17, $t18)], proj#0..16=[{exprs}], $condition=[$t19])
+              CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
\ No newline at end of file
diff --git a/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_top_usenull_true.yaml b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_top_usenull_true.yaml
new file mode 100644
index 00000000000..43b1ff58b73
--- /dev/null
+++ b/integ-test/src/test/resources/expectedOutput/calcite_no_pushdown/explain_top_usenull_true.yaml
@@ -0,0 +1,15 @@
+calcite:
+  logical: |
+    LogicalSystemLimit(fetch=[10000], type=[QUERY_SIZE_LIMIT])
+      LogicalProject(gender=[$0], state=[$1], count=[$2])
+        LogicalFilter(condition=[<=($3, 2)])
+          LogicalProject(gender=[$0], state=[$1], count=[$2], _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])
+            LogicalAggregate(group=[{0, 1}], count=[COUNT()])
+              LogicalProject(gender=[$4], state=[$7])
+                CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
+  physical: |
+    EnumerableLimit(fetch=[10000])
+      EnumerableCalc(expr#0..3=[{inputs}], expr#4=[2], expr#5=[<=($t3, $t4)], proj#0..2=[{exprs}], $condition=[$t5])
+        EnumerableWindow(window#0=[window(partition {0} order by [2 DESC] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])
+          EnumerableAggregate(group=[{4, 7}], count=[COUNT()])
+            CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])
\ No newline at end of file
diff --git a/ppl/src/main/antlr/OpenSearchPPLLexer.g4 b/ppl/src/main/antlr/OpenSearchPPLLexer.g4
index ba1e4960bb2..c6d28be69a3 100644
--- a/ppl/src/main/antlr/OpenSearchPPLLexer.g4
+++ b/ppl/src/main/antlr/OpenSearchPPLLexer.g4
@@ -111,6 +111,7 @@ PARTITIONS:                         'PARTITIONS';
 ALLNUM:                             'ALLNUM';
 DELIM:                              'DELIM';
 BUCKET_NULLABLE:                    'BUCKET_NULLABLE';
+USENULL:                            'USENULL';
 CENTROIDS:                          'CENTROIDS';
 ITERATIONS:                         'ITERATIONS';
 DISTANCE_TYPE:                      'DISTANCE_TYPE';
diff --git a/ppl/src/main/antlr/OpenSearchPPLParser.g4 b/ppl/src/main/antlr/OpenSearchPPLParser.g4
index d07af92e93c..3a06b624e47 100644
--- a/ppl/src/main/antlr/OpenSearchPPLParser.g4
+++ b/ppl/src/main/antlr/OpenSearchPPLParser.g4
@@ -59,8 +59,7 @@ commands
    | evalCommand
    | headCommand
    | binCommand
-   | topCommand
-   | rareCommand
+   | rareTopCommand
    | grokCommand
    | parseCommand
    | spathCommand
@@ -309,12 +308,14 @@ logSpanValue
    : LOG_WITH_BASE                                                   # logWithBaseSpan
    ;
 
-topCommand
-   : TOP (number = integerLiteral)? (COUNTFIELD EQUAL countfield = stringLiteral)? (SHOWCOUNT EQUAL showcount = booleanLiteral)? fieldList (byClause)?
+rareTopCommand
+   : (TOP | RARE) (number = integerLiteral)? rareTopOption* fieldList (byClause)?
    ;
 
-rareCommand
-   : RARE (number = integerLiteral)? (COUNTFIELD EQUAL countfield = stringLiteral)? (SHOWCOUNT EQUAL showcount = booleanLiteral)? fieldList (byClause)?
+rareTopOption
+   : COUNTFIELD EQUAL countField = stringLiteral
+   | SHOWCOUNT EQUAL showCount = booleanLiteral
+   | USENULL EQUAL useNull = booleanLiteral
    ;
 
 grokCommand
@@ -1454,6 +1455,7 @@ searchableKeyWord
    | ALLNUM
    | DELIM
    | BUCKET_NULLABLE
+   | USENULL
    | CENTROIDS
    | ITERATIONS
    | DISTANCE_TYPE
diff --git a/ppl/src/main/java/org/opensearch/sql/ppl/parser/AstBuilder.java b/ppl/src/main/java/org/opensearch/sql/ppl/parser/AstBuilder.java
index b7e33246027..8802dcbf3c9 100644
--- a/ppl/src/main/java/org/opensearch/sql/ppl/parser/AstBuilder.java
+++ b/ppl/src/main/java/org/opensearch/sql/ppl/parser/AstBuilder.java
@@ -696,26 +696,19 @@ private Set<Field> getUniqueFieldSet(FieldListContext ctx) {
     return uniqueFields;
   }
 
-  /** Rare command. */
+  /** Rare and Top commands. */
   @Override
-  public UnresolvedPlan visitRareCommand(OpenSearchPPLParser.RareCommandContext ctx) {
+  public UnresolvedPlan visitRareTopCommand(OpenSearchPPLParser.RareTopCommandContext ctx) {
     List<UnresolvedExpression> groupList =
         ctx.byClause() == null ? emptyList() : getGroupByList(ctx.byClause());
+    Integer noOfResults =
+        ctx.number != null
+            ? (Integer) ((Literal) expressionBuilder.visitIntegerLiteral(ctx.number)).getValue()
+            : 10;
     return new RareTopN(
-        CommandType.RARE,
-        ArgumentFactory.getArgumentList(ctx),
-        getFieldList(ctx.fieldList()),
-        groupList);
-  }
-
-  /** Top command. */
-  @Override
-  public UnresolvedPlan visitTopCommand(OpenSearchPPLParser.TopCommandContext ctx) {
-    List<UnresolvedExpression> groupList =
-        ctx.byClause() == null ? emptyList() : getGroupByList(ctx.byClause());
-    return new RareTopN(
-        CommandType.TOP,
-        ArgumentFactory.getArgumentList(ctx),
+        ctx.TOP() != null ? CommandType.TOP : CommandType.RARE,
+        noOfResults,
+        ArgumentFactory.getArgumentList(ctx, settings),
         getFieldList(ctx.fieldList()),
         groupList);
   }
diff --git a/ppl/src/main/java/org/opensearch/sql/ppl/utils/ArgumentFactory.java b/ppl/src/main/java/org/opensearch/sql/ppl/utils/ArgumentFactory.java
index 8f58e41f5e3..85481da2426 100644
--- a/ppl/src/main/java/org/opensearch/sql/ppl/utils/ArgumentFactory.java
+++ b/ppl/src/main/java/org/opensearch/sql/ppl/utils/ArgumentFactory.java
@@ -9,11 +9,13 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
 import org.antlr.v4.runtime.ParserRuleContext;
 import org.opensearch.sql.ast.expression.Argument;
 import org.opensearch.sql.ast.expression.DataType;
 import org.opensearch.sql.ast.expression.Literal;
 import org.opensearch.sql.ast.tree.Join;
+import org.opensearch.sql.ast.tree.RareTopN;
 import org.opensearch.sql.common.setting.Settings;
 import org.opensearch.sql.common.utils.StringUtils;
 import org.opensearch.sql.exception.SemanticCheckException;
@@ -25,10 +27,8 @@
 import org.opensearch.sql.ppl.antlr.parser.OpenSearchPPLParser.FieldsCommandContext;
 import org.opensearch.sql.ppl.antlr.parser.OpenSearchPPLParser.IntegerLiteralContext;
 import org.opensearch.sql.ppl.antlr.parser.OpenSearchPPLParser.PrefixSortFieldContext;
-import org.opensearch.sql.ppl.antlr.parser.OpenSearchPPLParser.RareCommandContext;
 import org.opensearch.sql.ppl.antlr.parser.OpenSearchPPLParser.SortFieldContext;
 import org.opensearch.sql.ppl.antlr.parser.OpenSearchPPLParser.SuffixSortFieldContext;
-import org.opensearch.sql.ppl.antlr.parser.OpenSearchPPLParser.TopCommandContext;
 
 /** Util class to get all arguments as a list from the PPL command. */
 public class ArgumentFactory {
@@ -179,42 +179,37 @@ private static Argument getTypeArgument(OpenSearchPPLParser.SortFieldExpressionC
     }
   }
 
-  /**
-   * Get list of {@link Argument}.
-   *
-   * @param ctx TopCommandContext instance
-   * @return the list of arguments fetched from the top command
-   */
-  public static List<Argument> getArgumentList(TopCommandContext ctx) {
-    return Arrays.asList(
-        ctx.number != null
-            ? new Argument("noOfResults", getArgumentValue(ctx.number))
-            : new Argument("noOfResults", new Literal(10, DataType.INTEGER)),
-        ctx.countfield != null
-            ? new Argument("countField", getArgumentValue(ctx.countfield))
-            : new Argument("countField", new Literal("count", DataType.STRING)),
-        ctx.showcount != null
-            ? new Argument("showCount", getArgumentValue(ctx.showcount))
-            : new Argument("showCount", new Literal(true, DataType.BOOLEAN)));
-  }
-
   /**
    * Get list of {@link Argument}.
    *
    * @param ctx RareCommandContext instance
+   * @param settings Settings instance
    * @return the list of argument with default number of results for the rare command
    */
-  public static List<Argument> getArgumentList(RareCommandContext ctx) {
-    return Arrays.asList(
-        ctx.number != null
-            ? new Argument("noOfResults", getArgumentValue(ctx.number))
-            : new Argument("noOfResults", new Literal(10, DataType.INTEGER)),
-        ctx.countfield != null
-            ? new Argument("countField", getArgumentValue(ctx.countfield))
-            : new Argument("countField", new Literal("count", DataType.STRING)),
-        ctx.showcount != null
-            ? new Argument("showCount", getArgumentValue(ctx.showcount))
-            : new Argument("showCount", new Literal(true, DataType.BOOLEAN)));
+  public static List<Argument> getArgumentList(
+      OpenSearchPPLParser.RareTopCommandContext ctx, Settings settings) {
+    List<Argument> list = new ArrayList<>();
+    Optional<OpenSearchPPLParser.RareTopOptionContext> opt =
+        ctx.rareTopOption().stream().filter(op -> op.countField != null).findFirst();
+    list.add(
+        new Argument(
+            RareTopN.Option.countField.name(),
+            opt.isPresent()
+                ? getArgumentValue(opt.get().countField)
+                : new Literal("count", DataType.STRING)));
+    opt = ctx.rareTopOption().stream().filter(op -> op.showCount != null).findFirst();
+    list.add(
+        new Argument(
+            RareTopN.Option.showCount.name(),
+            opt.isPresent() ? getArgumentValue(opt.get().showCount) : Literal.TRUE));
+    opt = ctx.rareTopOption().stream().filter(op -> op.useNull != null).findFirst();
+    list.add(
+        new Argument(
+            RareTopN.Option.useNull.name(),
+            opt.isPresent()
+                ? getArgumentValue(opt.get().useNull)
+                : legacyPreferred(settings) ? Literal.TRUE : Literal.FALSE));
+    return list;
   }
 
   /**
diff --git a/ppl/src/main/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizer.java b/ppl/src/main/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizer.java
index e392a682cef..f8c935175d0 100644
--- a/ppl/src/main/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizer.java
+++ b/ppl/src/main/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizer.java
@@ -382,14 +382,16 @@ public String visitWindow(Window node, String context) {
   public String visitRareTopN(RareTopN node, String context) {
     final String child = node.getChild().get(0).accept(this, context);
     ArgumentMap arguments = ArgumentMap.of(node.getArguments());
-    Integer noOfResults = (Integer) arguments.get("noOfResults").getValue();
-    String countField = (String) arguments.get("countField").getValue();
-    Boolean showCount = (Boolean) arguments.get("showCount").getValue();
+    Integer noOfResults = node.getNoOfResults();
+    String countField = (String) arguments.get(RareTopN.Option.countField.name()).getValue();
+    Boolean showCount = (Boolean) arguments.get(RareTopN.Option.showCount.name()).getValue();
+    Boolean useNull = (Boolean) arguments.get(RareTopN.Option.useNull.name()).getValue();
     String fields = visitFieldList(node.getFields());
     String group = visitExpressionList(node.getGroupExprList());
     String options =
         isCalciteEnabled(settings)
-            ? StringUtils.format("countield='%s' showcount=%s ", countField, showCount)
+            ? StringUtils.format(
+                "countield='%s' showcount=%s usenull=%s ", countField, showCount, useNull)
             : "";
     return StringUtils.format(
         "%s | %s %d %s%s",
diff --git a/ppl/src/test/java/org/opensearch/sql/ppl/calcite/CalcitePPLRareTopNTest.java b/ppl/src/test/java/org/opensearch/sql/ppl/calcite/CalcitePPLRareTopNTest.java
index 23dab511671..a4167b432ad 100644
--- a/ppl/src/test/java/org/opensearch/sql/ppl/calcite/CalcitePPLRareTopNTest.java
+++ b/ppl/src/test/java/org/opensearch/sql/ppl/calcite/CalcitePPLRareTopNTest.java
@@ -26,8 +26,8 @@ public void testRare() {
     String expectedLogical =
         "LogicalProject(JOB=[$0], count=[$1])\n"
             + "  LogicalFilter(condition=[<=($2, 10)])\n"
-            + "    LogicalProject(JOB=[$0], count=[$1], _row_number_=[ROW_NUMBER() OVER (ORDER BY"
-            + " $1)])\n"
+            + "    LogicalProject(JOB=[$0], count=[$1], _row_number_top_rare_=[ROW_NUMBER() OVER"
+            + " (ORDER BY $1)])\n"
             + "      LogicalAggregate(group=[{0}], count=[COUNT()])\n"
             + "        LogicalProject(JOB=[$2])\n"
             + "          LogicalTableScan(table=[[scott, EMP]])\n";
@@ -45,10 +45,10 @@ public void testRare() {
     String expectedSparkSql =
         "SELECT `JOB`, `count`\n"
             + "FROM (SELECT `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (ORDER BY COUNT(*) NULLS"
-            + " LAST) `_row_number_`\n"
+            + " LAST) `_row_number_top_rare_`\n"
             + "FROM `scott`.`EMP`\n"
             + "GROUP BY `JOB`) `t1`\n"
-            + "WHERE `_row_number_` <= 10";
+            + "WHERE `_row_number_top_rare_` <= 10";
     verifyPPLToSparkSQL(root, expectedSparkSql);
   }
 
@@ -59,8 +59,8 @@ public void testRareBy() {
     String expectedLogical =
         "LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2])\n"
             + "  LogicalFilter(condition=[<=($3, 10)])\n"
-            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2], _row_number_=[ROW_NUMBER()"
-            + " OVER (PARTITION BY $0 ORDER BY $2)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])\n"
             + "      LogicalAggregate(group=[{0, 1}], count=[COUNT()])\n"
             + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
             + "          LogicalTableScan(table=[[scott, EMP]])\n";
@@ -82,10 +82,10 @@ public void testRareBy() {
     String expectedSparkSql =
         "SELECT `DEPTNO`, `JOB`, `count`\n"
             + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (PARTITION BY"
-            + " `DEPTNO` ORDER BY COUNT(*) NULLS LAST) `_row_number_`\n"
+            + " `DEPTNO` ORDER BY COUNT(*) NULLS LAST) `_row_number_top_rare_`\n"
             + "FROM `scott`.`EMP`\n"
             + "GROUP BY `DEPTNO`, `JOB`) `t1`\n"
-            + "WHERE `_row_number_` <= 10";
+            + "WHERE `_row_number_top_rare_` <= 10";
     verifyPPLToSparkSQL(root, expectedSparkSql);
   }
 
@@ -96,8 +96,8 @@ public void testRareDisableShowCount() {
     String expectedLogical =
         "LogicalProject(DEPTNO=[$0], JOB=[$1])\n"
             + "  LogicalFilter(condition=[<=($3, 10)])\n"
-            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2], _row_number_=[ROW_NUMBER()"
-            + " OVER (PARTITION BY $0 ORDER BY $2)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])\n"
             + "      LogicalAggregate(group=[{0, 1}], count=[COUNT()])\n"
             + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
             + "          LogicalTableScan(table=[[scott, EMP]])\n";
@@ -119,10 +119,10 @@ public void testRareDisableShowCount() {
     String expectedSparkSql =
         "SELECT `DEPTNO`, `JOB`\n"
             + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (PARTITION BY"
-            + " `DEPTNO` ORDER BY COUNT(*) NULLS LAST) `_row_number_`\n"
+            + " `DEPTNO` ORDER BY COUNT(*) NULLS LAST) `_row_number_top_rare_`\n"
             + "FROM `scott`.`EMP`\n"
             + "GROUP BY `DEPTNO`, `JOB`) `t1`\n"
-            + "WHERE `_row_number_` <= 10";
+            + "WHERE `_row_number_top_rare_` <= 10";
     verifyPPLToSparkSQL(root, expectedSparkSql);
   }
 
@@ -133,8 +133,8 @@ public void testRareCountField() {
     String expectedLogical =
         "LogicalProject(DEPTNO=[$0], JOB=[$1], my_cnt=[$2])\n"
             + "  LogicalFilter(condition=[<=($3, 10)])\n"
-            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], my_cnt=[$2], _row_number_=[ROW_NUMBER()"
-            + " OVER (PARTITION BY $0 ORDER BY $2)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], my_cnt=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])\n"
             + "      LogicalAggregate(group=[{0, 1}], my_cnt=[COUNT()])\n"
             + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
             + "          LogicalTableScan(table=[[scott, EMP]])\n";
@@ -156,10 +156,49 @@ public void testRareCountField() {
     String expectedSparkSql =
         "SELECT `DEPTNO`, `JOB`, `my_cnt`\n"
             + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `my_cnt`, ROW_NUMBER() OVER (PARTITION BY"
-            + " `DEPTNO` ORDER BY COUNT(*) NULLS LAST) `_row_number_`\n"
+            + " `DEPTNO` ORDER BY COUNT(*) NULLS LAST) `_row_number_top_rare_`\n"
             + "FROM `scott`.`EMP`\n"
             + "GROUP BY `DEPTNO`, `JOB`) `t1`\n"
-            + "WHERE `_row_number_` <= 10";
+            + "WHERE `_row_number_top_rare_` <= 10";
+    verifyPPLToSparkSQL(root, expectedSparkSql);
+  }
+
+  @Test
+  public void testRareUseNullFalse() {
+    String ppl = "source=EMP | rare usenull=false JOB by DEPTNO";
+    RelNode root = getRelNode(ppl);
+    String expectedLogical =
+        "LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2])\n"
+            + "  LogicalFilter(condition=[<=($3, 10)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2)])\n"
+            + "      LogicalAggregate(group=[{0, 1}], count=[COUNT()])\n"
+            + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
+            + "          LogicalFilter(condition=[AND(IS NOT NULL($7), IS NOT NULL($2))])\n"
+            + "            LogicalTableScan(table=[[scott, EMP]])\n";
+    verifyLogical(root, expectedLogical);
+
+    String expectedResult =
+        ""
+            + "DEPTNO=20; JOB=MANAGER; count=1\n"
+            + "DEPTNO=20; JOB=CLERK; count=2\n"
+            + "DEPTNO=20; JOB=ANALYST; count=2\n"
+            + "DEPTNO=10; JOB=MANAGER; count=1\n"
+            + "DEPTNO=10; JOB=CLERK; count=1\n"
+            + "DEPTNO=10; JOB=PRESIDENT; count=1\n"
+            + "DEPTNO=30; JOB=MANAGER; count=1\n"
+            + "DEPTNO=30; JOB=CLERK; count=1\n"
+            + "DEPTNO=30; JOB=SALESMAN; count=4\n";
+    verifyResult(root, expectedResult);
+
+    String expectedSparkSql =
+        "SELECT `DEPTNO`, `JOB`, `count`\n"
+            + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (PARTITION BY"
+            + " `DEPTNO` ORDER BY COUNT(*) NULLS LAST) `_row_number_top_rare_`\n"
+            + "FROM `scott`.`EMP`\n"
+            + "WHERE `DEPTNO` IS NOT NULL AND `JOB` IS NOT NULL\n"
+            + "GROUP BY `DEPTNO`, `JOB`) `t2`\n"
+            + "WHERE `_row_number_top_rare_` <= 10";
     verifyPPLToSparkSQL(root, expectedSparkSql);
   }
 
@@ -182,4 +221,187 @@ public void failWithDuplicatedName() {
           is("Field `DEPTNO` is existed, change the count field by setting countfield='xyz'"));
     }
   }
+
+  @Test
+  public void testTop() {
+    String ppl = "source=EMP | top JOB";
+    RelNode root = getRelNode(ppl);
+    String expectedLogical =
+        "LogicalProject(JOB=[$0], count=[$1])\n"
+            + "  LogicalFilter(condition=[<=($2, 10)])\n"
+            + "    LogicalProject(JOB=[$0], count=[$1], _row_number_top_rare_=[ROW_NUMBER() OVER"
+            + " (ORDER BY $1 DESC)])\n"
+            + "      LogicalAggregate(group=[{0}], count=[COUNT()])\n"
+            + "        LogicalProject(JOB=[$2])\n"
+            + "          LogicalTableScan(table=[[scott, EMP]])\n";
+    verifyLogical(root, expectedLogical);
+
+    String expectedResult =
+        ""
+            + "JOB=SALESMAN; count=4\n"
+            + "JOB=CLERK; count=4\n"
+            + "JOB=MANAGER; count=3\n"
+            + "JOB=ANALYST; count=2\n"
+            + "JOB=PRESIDENT; count=1\n";
+    verifyResult(root, expectedResult);
+
+    String expectedSparkSql =
+        "SELECT `JOB`, `count`\n"
+            + "FROM (SELECT `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (ORDER BY COUNT(*) DESC"
+            + " NULLS FIRST) `_row_number_top_rare_`\n"
+            + "FROM `scott`.`EMP`\n"
+            + "GROUP BY `JOB`) `t1`\n"
+            + "WHERE `_row_number_top_rare_` <= 10";
+    verifyPPLToSparkSQL(root, expectedSparkSql);
+  }
+
+  @Test
+  public void testTopBy() {
+    String ppl = "source=EMP | top JOB by DEPTNO";
+    RelNode root = getRelNode(ppl);
+    String expectedLogical =
+        "LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2])\n"
+            + "  LogicalFilter(condition=[<=($3, 10)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])\n"
+            + "      LogicalAggregate(group=[{0, 1}], count=[COUNT()])\n"
+            + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
+            + "          LogicalTableScan(table=[[scott, EMP]])\n";
+    verifyLogical(root, expectedLogical);
+
+    String expectedResult =
+        ""
+            + "DEPTNO=20; JOB=CLERK; count=2\n"
+            + "DEPTNO=20; JOB=ANALYST; count=2\n"
+            + "DEPTNO=20; JOB=MANAGER; count=1\n"
+            + "DEPTNO=10; JOB=MANAGER; count=1\n"
+            + "DEPTNO=10; JOB=CLERK; count=1\n"
+            + "DEPTNO=10; JOB=PRESIDENT; count=1\n"
+            + "DEPTNO=30; JOB=SALESMAN; count=4\n"
+            + "DEPTNO=30; JOB=MANAGER; count=1\n"
+            + "DEPTNO=30; JOB=CLERK; count=1\n";
+    verifyResult(root, expectedResult);
+
+    String expectedSparkSql =
+        "SELECT `DEPTNO`, `JOB`, `count`\n"
+            + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (PARTITION BY"
+            + " `DEPTNO` ORDER BY COUNT(*) DESC NULLS FIRST) `_row_number_top_rare_`\n"
+            + "FROM `scott`.`EMP`\n"
+            + "GROUP BY `DEPTNO`, `JOB`) `t1`\n"
+            + "WHERE `_row_number_top_rare_` <= 10";
+    verifyPPLToSparkSQL(root, expectedSparkSql);
+  }
+
+  @Test
+  public void testTopDisableShowCount() {
+    String ppl = "source=EMP | top showcount=false JOB by DEPTNO";
+    RelNode root = getRelNode(ppl);
+    String expectedLogical =
+        "LogicalProject(DEPTNO=[$0], JOB=[$1])\n"
+            + "  LogicalFilter(condition=[<=($3, 10)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])\n"
+            + "      LogicalAggregate(group=[{0, 1}], count=[COUNT()])\n"
+            + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
+            + "          LogicalTableScan(table=[[scott, EMP]])\n";
+    verifyLogical(root, expectedLogical);
+
+    String expectedResult =
+        ""
+            + "DEPTNO=20; JOB=CLERK\n"
+            + "DEPTNO=20; JOB=ANALYST\n"
+            + "DEPTNO=20; JOB=MANAGER\n"
+            + "DEPTNO=10; JOB=MANAGER\n"
+            + "DEPTNO=10; JOB=CLERK\n"
+            + "DEPTNO=10; JOB=PRESIDENT\n"
+            + "DEPTNO=30; JOB=SALESMAN\n"
+            + "DEPTNO=30; JOB=MANAGER\n"
+            + "DEPTNO=30; JOB=CLERK\n";
+    verifyResult(root, expectedResult);
+
+    String expectedSparkSql =
+        "SELECT `DEPTNO`, `JOB`\n"
+            + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (PARTITION BY"
+            + " `DEPTNO` ORDER BY COUNT(*) DESC NULLS FIRST) `_row_number_top_rare_`\n"
+            + "FROM `scott`.`EMP`\n"
+            + "GROUP BY `DEPTNO`, `JOB`) `t1`\n"
+            + "WHERE `_row_number_top_rare_` <= 10";
+    verifyPPLToSparkSQL(root, expectedSparkSql);
+  }
+
+  @Test
+  public void testTopCountField() {
+    String ppl = "source=EMP | top countfield='my_cnt' JOB by DEPTNO";
+    RelNode root = getRelNode(ppl);
+    String expectedLogical =
+        "LogicalProject(DEPTNO=[$0], JOB=[$1], my_cnt=[$2])\n"
+            + "  LogicalFilter(condition=[<=($3, 10)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], my_cnt=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])\n"
+            + "      LogicalAggregate(group=[{0, 1}], my_cnt=[COUNT()])\n"
+            + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
+            + "          LogicalTableScan(table=[[scott, EMP]])\n";
+    verifyLogical(root, expectedLogical);
+
+    String expectedResult =
+        ""
+            + "DEPTNO=20; JOB=CLERK; my_cnt=2\n"
+            + "DEPTNO=20; JOB=ANALYST; my_cnt=2\n"
+            + "DEPTNO=20; JOB=MANAGER; my_cnt=1\n"
+            + "DEPTNO=10; JOB=MANAGER; my_cnt=1\n"
+            + "DEPTNO=10; JOB=CLERK; my_cnt=1\n"
+            + "DEPTNO=10; JOB=PRESIDENT; my_cnt=1\n"
+            + "DEPTNO=30; JOB=SALESMAN; my_cnt=4\n"
+            + "DEPTNO=30; JOB=MANAGER; my_cnt=1\n"
+            + "DEPTNO=30; JOB=CLERK; my_cnt=1\n";
+    verifyResult(root, expectedResult);
+
+    String expectedSparkSql =
+        "SELECT `DEPTNO`, `JOB`, `my_cnt`\n"
+            + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `my_cnt`, ROW_NUMBER() OVER (PARTITION BY"
+            + " `DEPTNO` ORDER BY COUNT(*) DESC NULLS FIRST) `_row_number_top_rare_`\n"
+            + "FROM `scott`.`EMP`\n"
+            + "GROUP BY `DEPTNO`, `JOB`) `t1`\n"
+            + "WHERE `_row_number_top_rare_` <= 10";
+    verifyPPLToSparkSQL(root, expectedSparkSql);
+  }
+
+  @Test
+  public void testTopUseNullFalse() {
+    String ppl = "source=EMP | top usenull=false JOB by DEPTNO";
+    RelNode root = getRelNode(ppl);
+    String expectedLogical =
+        "LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2])\n"
+            + "  LogicalFilter(condition=[<=($3, 10)])\n"
+            + "    LogicalProject(DEPTNO=[$0], JOB=[$1], count=[$2],"
+            + " _row_number_top_rare_=[ROW_NUMBER() OVER (PARTITION BY $0 ORDER BY $2 DESC)])\n"
+            + "      LogicalAggregate(group=[{0, 1}], count=[COUNT()])\n"
+            + "        LogicalProject(DEPTNO=[$7], JOB=[$2])\n"
+            + "          LogicalFilter(condition=[AND(IS NOT NULL($7), IS NOT NULL($2))])\n"
+            + "            LogicalTableScan(table=[[scott, EMP]])\n";
+    verifyLogical(root, expectedLogical);
+
+    String expectedResult =
+        ""
+            + "DEPTNO=20; JOB=CLERK; count=2\n"
+            + "DEPTNO=20; JOB=ANALYST; count=2\n"
+            + "DEPTNO=20; JOB=MANAGER; count=1\n"
+            + "DEPTNO=10; JOB=MANAGER; count=1\n"
+            + "DEPTNO=10; JOB=CLERK; count=1\n"
+            + "DEPTNO=10; JOB=PRESIDENT; count=1\n"
+            + "DEPTNO=30; JOB=SALESMAN; count=4\n"
+            + "DEPTNO=30; JOB=MANAGER; count=1\n"
+            + "DEPTNO=30; JOB=CLERK; count=1\n";
+    verifyResult(root, expectedResult);
+
+    String expectedSparkSql =
+        "SELECT `DEPTNO`, `JOB`, `count`\n"
+            + "FROM (SELECT `DEPTNO`, `JOB`, COUNT(*) `count`, ROW_NUMBER() OVER (PARTITION BY"
+            + " `DEPTNO` ORDER BY COUNT(*) DESC NULLS FIRST) `_row_number_top_rare_`\n"
+            + "FROM `scott`.`EMP`\n"
+            + "WHERE `DEPTNO` IS NOT NULL AND `JOB` IS NOT NULL\n"
+            + "GROUP BY `DEPTNO`, `JOB`) `t2`\n"
+            + "WHERE `_row_number_top_rare_` <= 10";
+    verifyPPLToSparkSQL(root, expectedSparkSql);
+  }
 }
diff --git a/ppl/src/test/java/org/opensearch/sql/ppl/parser/AstBuilderTest.java b/ppl/src/test/java/org/opensearch/sql/ppl/parser/AstBuilderTest.java
index 300c4099e1b..be43b64cfa4 100644
--- a/ppl/src/test/java/org/opensearch/sql/ppl/parser/AstBuilderTest.java
+++ b/ppl/src/test/java/org/opensearch/sql/ppl/parser/AstBuilderTest.java
@@ -729,7 +729,8 @@ public void testRareCommand() {
             exprList(
                 argument("noOfResults", intLiteral(10)),
                 argument("countField", stringLiteral("count")),
-                argument("showCount", booleanLiteral(true))),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(true))),
             emptyList(),
             field("a")));
   }
@@ -744,7 +745,8 @@ public void testRareCommandWithGroupBy() {
             exprList(
                 argument("noOfResults", intLiteral(10)),
                 argument("countField", stringLiteral("count")),
-                argument("showCount", booleanLiteral(true))),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(true))),
             exprList(field("b")),
             field("a")));
   }
@@ -759,7 +761,8 @@ public void testRareCommandWithMultipleFields() {
             exprList(
                 argument("noOfResults", intLiteral(10)),
                 argument("countField", stringLiteral("count")),
-                argument("showCount", booleanLiteral(true))),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(true))),
             exprList(field("c")),
             field("a"),
             field("b")));
@@ -775,7 +778,8 @@ public void testTopCommandWithN() {
             exprList(
                 argument("noOfResults", intLiteral(1)),
                 argument("countField", stringLiteral("count")),
-                argument("showCount", booleanLiteral(true))),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(true))),
             emptyList(),
             field("a")));
   }
@@ -790,7 +794,8 @@ public void testTopCommandWithoutNAndGroupBy() {
             exprList(
                 argument("noOfResults", intLiteral(10)),
                 argument("countField", stringLiteral("count")),
-                argument("showCount", booleanLiteral(true))),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(true))),
             emptyList(),
             field("a")));
   }
@@ -805,7 +810,8 @@ public void testTopCommandWithNAndGroupBy() {
             exprList(
                 argument("noOfResults", intLiteral(1)),
                 argument("countField", stringLiteral("count")),
-                argument("showCount", booleanLiteral(true))),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(true))),
             exprList(field("b")),
             field("a")));
   }
@@ -820,12 +826,46 @@ public void testTopCommandWithMultipleFields() {
             exprList(
                 argument("noOfResults", intLiteral(1)),
                 argument("countField", stringLiteral("count")),
-                argument("showCount", booleanLiteral(true))),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(true))),
             exprList(field("c")),
             field("a"),
             field("b")));
   }
 
+  @Test
+  public void testTopCommandWithUseNullFalse() {
+    assertEqual(
+        "source=t | top 1 usenull=false a by b",
+        rareTopN(
+            relation("t"),
+            CommandType.TOP,
+            exprList(
+                argument("noOfResults", intLiteral(1)),
+                argument("countField", stringLiteral("count")),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(false))),
+            exprList(field("b")),
+            field("a")));
+  }
+
+  @Test
+  public void testTopCommandWithLegacyFalse() {
+    when(settings.getSettingValue(Key.PPL_SYNTAX_LEGACY_PREFERRED)).thenReturn(false);
+    assertEqual(
+        "source=t | top 1 a by b",
+        rareTopN(
+            relation("t"),
+            CommandType.TOP,
+            exprList(
+                argument("noOfResults", intLiteral(1)),
+                argument("countField", stringLiteral("count")),
+                argument("showCount", booleanLiteral(true)),
+                argument("useNull", booleanLiteral(false))),
+            exprList(field("b")),
+            field("a")));
+  }
+
   @Test
   public void testGrokCommand() {
     assertEqual(
diff --git a/ppl/src/test/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizerTest.java b/ppl/src/test/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizerTest.java
index 6de9acacfe1..2f18db5c995 100644
--- a/ppl/src/test/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizerTest.java
+++ b/ppl/src/test/java/org/opensearch/sql/ppl/utils/PPLQueryDataAnonymizerTest.java
@@ -311,7 +311,8 @@ public void testTopCommandWithNAndGroupBy() {
   public void testRareCommandWithGroupByWithCalcite() {
     when(settings.getSettingValue(Key.CALCITE_ENGINE_ENABLED)).thenReturn(true);
     assertEquals(
-        "source=table | rare 10 countield='count' showcount=true identifier by identifier",
+        "source=table | rare 10 countield='count' showcount=true usenull=true identifier by"
+            + " identifier",
         anonymize("source=t | rare a by b"));
   }
 
@@ -319,7 +320,8 @@ public void testRareCommandWithGroupByWithCalcite() {
   public void testTopCommandWithNAndGroupByWithCalcite() {
     when(settings.getSettingValue(Key.CALCITE_ENGINE_ENABLED)).thenReturn(true);
     assertEquals(
-        "source=table | top 1 countield='count' showcount=true identifier by identifier",
+        "source=table | top 1 countield='count' showcount=true usenull=true identifier by"
+            + " identifier",
         anonymize("source=t | top 1 a by b"));
   }