improved sql parser.

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/ast/SQLServerOutput.java

@@ -58,4 +58,21 @@ public class SQLServerOutput extends SQLServerObjectImpl {
         return selectList;
     }
 
+    public SQLServerOutput clone() {
+        SQLServerOutput x = new SQLServerOutput();
+        if (into != null) {
+            x.setInto(into.clone());
+        }
+        for (SQLExpr c : columns) {
+            SQLExpr c2 = c.clone();
+            c2.setParent(x);
+            x.columns.add(c2);
+        }
+        for (SQLSelectItem item : selectList) {
+            SQLSelectItem item2 = item.clone();
+            item2.setParent(x);
+            x.selectList.add(item2);
+        }
+        return x;
+    }
 }

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/ast/SQLServerTop.java

@@ -65,4 +65,13 @@ public class SQLServerTop extends SQLServerObjectImpl {
         visitor.endVisit(this);
     }
 
+    public SQLServerTop clone() {
+        SQLServerTop x = new SQLServerTop();
+        if (expr != null) {
+            x.setExpr(expr.clone());
+        }
+        x.percent = percent;
+        x.withTies = withTies;
+        return x;
+    }
 }

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/ast/stmt/SQLServerInsertStatement.java

@@ -33,6 +33,17 @@ public class SQLServerInsertStatement extends SQLInsertStatement implements SQLS
 
     private SQLServerOutput    output;
 
+    public void cloneTo(SQLServerInsertStatement x) {
+        super.cloneTo(x);
+        x.defaultValues = defaultValues;
+        if (top != null) {
+            x.setTop(top.clone());
+        }
+        if (output != null) {
+            x.setOutput(output.clone());
+        }
+    }
+
     @Override
     protected void accept0(SQLASTVisitor visitor) {
         this.accept0((SQLServerASTVisitor) visitor);
@@ -76,4 +87,9 @@ public class SQLServerInsertStatement extends SQLInsertStatement implements SQLS
         this.top = top;
     }
 
+    public SQLServerInsertStatement clone() {
+        SQLServerInsertStatement x = new SQLServerInsertStatement();
+        cloneTo(x);
+        return x;
+    }
 }