diff --git a/ppl-spark-integration/src/main/java/org/opensearch/sql/ast/tree/AppendCol.java b/ppl-spark-integration/src/main/java/org/opensearch/sql/ast/tree/AppendCol.java
index b98d08caa..421821739 100644
--- a/ppl-spark-integration/src/main/java/org/opensearch/sql/ast/tree/AppendCol.java
+++ b/ppl-spark-integration/src/main/java/org/opensearch/sql/ast/tree/AppendCol.java
@@ -26,9 +26,9 @@
 @AllArgsConstructor
 public class AppendCol extends UnresolvedPlan {
 
-    public boolean override;
+    private final boolean override;
 
-    private UnresolvedPlan subSearch;
+    private final UnresolvedPlan subSearch;
 
     private UnresolvedPlan child;
 
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 c59194c3a..fba8cf4f2 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
@@ -296,7 +296,7 @@ public LogicalPlan visitAppendCol(AppendCol node, CatalystPlanContext context) {
                     new Join.JoinHint());
 
             // Remove the APPEND_ID and duplicated field on T1 if override option present.
-            if (node.override) {
+            if (node.isOverride()) {
                 List<Expression> attrToOverride = AppendColCatalystUtils.getOverridedList(subSearch, TABLE_LHS);
                 if (attrToOverride != null &&
                     !attrToOverride.isEmpty() &&