diff --git a/src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/SQLSelectSubqueryQuery.java b/src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/SQLSelectSubqueryQuery.java
deleted file mode 100644
index e4061b015a..0000000000
--- a/src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/SQLSelectSubqueryQuery.java
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Copyright 1999-2011 Alibaba Group Holding Ltd.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.alibaba.druid.sql.dialect.oracle.ast.stmt;
-
-import com.alibaba.druid.sql.ast.statement.SQLSelectQuery;
-import com.alibaba.druid.sql.visitor.SQLASTVisitor;
-
-public class SQLSelectSubqueryQuery extends SQLSelectQuery {
-
-    private static final long serialVersionUID = 1L;
-
-    public SQLSelectSubqueryQuery(){
-
-    }
-
-    protected void accept0(SQLASTVisitor visitor) {
-        visitor.visit(this);
-
-        visitor.endVisit(this);
-    }
-}
diff --git a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java
index 3513d12bc2..ef161813fb 100644
--- a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java
+++ b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java
@@ -77,7 +77,6 @@ import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
 import com.alibaba.druid.sql.ast.statement.SQLUniqueConstraint;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateSetItem;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
-import com.alibaba.druid.sql.dialect.oracle.ast.stmt.SQLSelectSubqueryQuery;
 
 public class SQLASTOutputVisitor extends SQLASTVisitorAdapter {
 
@@ -519,10 +518,6 @@ public class SQLASTOutputVisitor extends SQLASTVisitorAdapter {
         return false;
     }
 
-    public boolean visit(SQLSelectSubqueryQuery x) {
-        throw new UnsupportedOperationException();
-    }
-
     public boolean visit(SQLVariantRefExpr x) {
         print(x.getName());
         return false;
diff --git a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitor.java b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitor.java
index 15ee67f6af..133a1c2c10 100644
--- a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitor.java
+++ b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitor.java
@@ -72,7 +72,6 @@ import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
 import com.alibaba.druid.sql.ast.statement.SQLUniqueConstraint;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateSetItem;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
-import com.alibaba.druid.sql.dialect.oracle.ast.stmt.SQLSelectSubqueryQuery;
 
 public interface SQLASTVisitor {
 
@@ -154,10 +153,6 @@ public interface SQLASTVisitor {
 
     void endVisit(SQLCastExpr x);
 
-    void endVisit(SQLSelectSubqueryQuery x);
-
-    boolean visit(SQLSelectSubqueryQuery x);
-
     boolean visit(SQLSelectStatement astNode);
 
     void endVisit(SQLAggregateExpr astNode);
diff --git a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitorAdapter.java b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitorAdapter.java
index 225c5aa842..336e78ab37 100644
--- a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitorAdapter.java
+++ b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitorAdapter.java
@@ -73,7 +73,6 @@ import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
 import com.alibaba.druid.sql.ast.statement.SQLUniqueConstraint;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateSetItem;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
-import com.alibaba.druid.sql.dialect.oracle.ast.stmt.SQLSelectSubqueryQuery;
 
 public class SQLASTVisitorAdapter implements SQLASTVisitor {
 
@@ -212,12 +211,6 @@ public class SQLASTVisitorAdapter implements SQLASTVisitor {
     public void endVisit(SQLCastExpr x) {
     }
 
-    public void endVisit(SQLSelectSubqueryQuery x) {
-    }
-
-    public boolean visit(SQLSelectSubqueryQuery x) {
-        return true;
-    }
 
     public boolean visit(SQLSelectStatement astNode) {
         return true;