    public function beforeSave () {
        $valid = parent::beforeSave ();
        if ($valid && $this->_typeChanged) {
            $table = Yii::app()->db->schema->tables[$this->myTableName];
            $existing = array_key_exists($this->fieldName, $table->columns) && 
                $table->columns[$this->fieldName] instanceof CDbColumnSchema;
            if($existing){ 
                $valid = $this->modifyColumn();
            }
        }
        return $valid;
    }
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.