diff --git a/ppl-spark-integration/src/main/java/org/opensearch/sql/ppl/CatalystQueryPlanVisitor.java b/ppl-spark-integration/src/main/java/org/opensearch/sql/ppl/CatalystQueryPlanVisitor.java
index 1652961e9..53e529575 100644
--- a/ppl-spark-integration/src/main/java/org/opensearch/sql/ppl/CatalystQueryPlanVisitor.java
+++ b/ppl-spark-integration/src/main/java/org/opensearch/sql/ppl/CatalystQueryPlanVisitor.java
@@ -339,6 +339,7 @@ private org.apache.spark.sql.catalyst.plans.logical.SubqueryAlias getRowNumStarP
         expressionAnalyzer.visitLiteral(
                 new Literal(DUMMY_SORT_FIELD, DataType.STRING), context);
         Expression strExp = context.popNamedParseExpressions().get();
+        // Literal("x")
         SortOrder sortOrder = SortUtils.sortOrder(strExp, false);
 
         NamedExpression appendCol = WindowSpecTransformer.buildRowNumber(seq(), seq(sortOrder));
diff --git a/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanAppendColCommandTranslatorTestSuite.scala b/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanAppendColCommandTranslatorTestSuite.scala
new file mode 100644
index 000000000..ef9a26ae1
--- /dev/null
+++ b/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanAppendColCommandTranslatorTestSuite.scala
@@ -0,0 +1,184 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.flint.spark.ppl
+
+import org.opensearch.flint.spark.ppl.PlaneUtils.plan
+import org.opensearch.sql.ppl.{CatalystPlanContext, CatalystQueryPlanVisitor}
+import org.opensearch.sql.ppl.utils.SortUtils
+
+import org.apache.spark.SparkFunSuite
+import org.apache.spark.sql.catalyst.analysis.{
+  UnresolvedAttribute,
+  UnresolvedFunction,
+  UnresolvedRelation,
+  UnresolvedStar
+}
+import org.apache.spark.sql.catalyst.expressions.{
+  Alias,
+  And,
+  CurrentRow,
+  EqualTo,
+  Literal,
+  RowFrame,
+  RowNumber,
+  SpecifiedWindowFrame,
+  UnboundedPreceding,
+  WindowExpression,
+  WindowSpecDefinition
+}
+import org.apache.spark.sql.catalyst.plans.{LeftOuter, PlanTest}
+import org.apache.spark.sql.catalyst.plans.logical._
+
+import org.scalatest.matchers.should.Matchers
+
+class PPLLogicalPlanAppendColCommandTranslatorTestSuite
+    extends SparkFunSuite
+    with PlanTest
+    with LogicalPlanTestUtils
+    with Matchers {
+
+  private val planTransformer = new CatalystQueryPlanVisitor()
+  private val pplParser = new PPLSyntaxParser()
+
+  private val ROW_NUMBER_AGGREGATION = Alias(
+    WindowExpression(
+      RowNumber(),
+      WindowSpecDefinition(
+        Nil,
+        SortUtils.sortOrder(Literal("1"), false) :: Nil,
+        SpecifiedWindowFrame(RowFrame, UnboundedPreceding, CurrentRow))),
+    "_row_number_")()
+
+  private val COUNT_STAR = Alias(
+    UnresolvedFunction(Seq("COUNT"),
+    Seq(UnresolvedStar(None)),
+    isDistinct = false),
+    "count()")()
+
+  private val AGE_ALIAS = Alias(UnresolvedAttribute("age"), "age")()
+
+  private val RELATION_EMPLOYEES = UnresolvedRelation(Seq("employees"))
+
+  private val T12_JOIN_CONDITION = EqualTo(
+    UnresolvedAttribute("T1._row_number_"), UnresolvedAttribute("T2._row_number_"))
+
+  private val T12_COLUMNS_SEQ = Seq(
+    UnresolvedAttribute("T1._row_number_"), UnresolvedAttribute("T2._row_number_"))
+
+  /**
+   * Expected:
+   'Project [*]
+   +- 'DataFrameDropColumns ['T1._row_number_, 'T2._row_number_]
+   +- 'Join LeftOuter, ('T1._row_number_ = 'T2._row_number_)
+   :- 'SubqueryAlias T1
+   :  +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST, specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#1, *]
+   :     +- 'UnresolvedRelation [employees], [], false
+   +- 'SubqueryAlias T2
+   +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST, specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#5, *]
+   +- 'Aggregate ['age AS age#3], ['COUNT(*) AS count()#2, 'age AS age#3]
+   +- 'UnresolvedRelation [employees], [], false
+   */
+  test("test AppendCol with NO transformation on main") {
+    val context = new CatalystPlanContext
+    val logicalPlan = planTransformer.visit(
+      plan(pplParser, "source=employees | APPENDCOL [stats count() by age];"),
+      context
+    )
+
+    /*
+      :- 'SubqueryAlias T1
+      :  +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST, specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#7, *]
+      :     +- 'UnresolvedRelation [relation], [], false
+     */
+    val t1 = SubqueryAlias("T1", Project(
+        Seq(ROW_NUMBER_AGGREGATION, UnresolvedStar(None)),
+        RELATION_EMPLOYEES))
+
+    /*
+    +- 'SubqueryAlias T2
+      +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST,
+          specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#11, *]
+        +- 'Aggregate ['age AS age#9], ['COUNT(*) AS count()#8, 'age AS age#10]
+           +- 'UnresolvedRelation [relation], [], false
+     */
+    val t2 = SubqueryAlias("T2", Project(
+      Seq(ROW_NUMBER_AGGREGATION, UnresolvedStar(None)),
+      Aggregate(
+        AGE_ALIAS :: Nil, Seq(COUNT_STAR, AGE_ALIAS),
+        RELATION_EMPLOYEES)
+    ))
+
+    val result = Project(Seq(UnresolvedStar(None)),
+        DataFrameDropColumns(T12_COLUMNS_SEQ,
+          Join(t1, t2, LeftOuter, Some(T12_JOIN_CONDITION), JoinHint.NONE)))
+
+    comparePlans(logicalPlan, result, checkAnalysis = false)
+  }
+
+  /**
+   * 'Project [*]
+   * +- 'DataFrameDropColumns ['T1._row_number_, 'T2._row_number_]
+   * +- 'Join LeftOuter, ('T1._row_number_ = 'T2._row_number_)
+   * :- 'SubqueryAlias T1
+   * :  +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST, specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#11, *]
+   * :     +- 'Project ['age, 'dept, 'salary]
+   * :        +- 'UnresolvedRelation [relation], [], false
+   * +- 'SubqueryAlias T2
+   * +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST, specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#15, *]
+   * +- 'Aggregate ['age AS age#13], ['COUNT(*) AS count()#12, 'age AS age#13]
+   * +- 'UnresolvedRelation [relation], [], false
+   */
+  test("test AppendCol with transformation on main-search") {
+    val context = new CatalystPlanContext
+    val logicalPlan = planTransformer.visit(
+      plan(pplParser, "source=employees | FIELDS age, dept, salary | APPENDCOL [stats count() by age];"),
+      context
+    )
+
+    /*
+      :- 'SubqueryAlias T1
+      :  +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST,
+                specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#11, *]
+      :     +- 'Project ['age, 'dept, 'salary]
+      :        +- 'UnresolvedRelation [relation], [], false
+     */
+    val t1 = SubqueryAlias("T1", Project(
+      Seq(ROW_NUMBER_AGGREGATION, UnresolvedStar(None)),
+      Project(Seq(
+        UnresolvedAttribute("age"),
+        UnresolvedAttribute("dept"),
+        UnresolvedAttribute("salary")), RELATION_EMPLOYEES)))
+
+
+    /*
+    +- 'SubqueryAlias T2
+      +- 'Project [row_number() windowspecdefinition(1 DESC NULLS LAST,
+          specifiedwindowframe(RowFrame, unboundedpreceding$(), currentrow$())) AS _row_number_#11, *]
+        +- 'Aggregate ['age AS age#9], ['COUNT(*) AS count()#8, 'age AS age#10]
+           +- 'UnresolvedRelation [relation], [], false
+     */
+    val t2 = SubqueryAlias("T2", Project(
+      Seq(ROW_NUMBER_AGGREGATION, UnresolvedStar(None)),
+      Aggregate(
+        AGE_ALIAS :: Nil, Seq(COUNT_STAR, AGE_ALIAS),
+        RELATION_EMPLOYEES)
+    ))
+
+    val result = Project(Seq(UnresolvedStar(None)),
+      DataFrameDropColumns(T12_COLUMNS_SEQ,
+        Join(t1, t2, LeftOuter, Some(T12_JOIN_CONDITION), JoinHint.NONE)))
+
+    // scalastyle:off
+    println(logicalPlan)
+    println(result)
+
+    comparePlans(logicalPlan, result, checkAnalysis = false)
+
+  }
+
+
+
+}