public virtual string GetSqlCommand()

        {

            string key =this.GetGuid();

            StringBuilder sb = new StringBuilder(" if exists (select * from "+this.GetTableName()+" where "+key+" = '"+this.GetPropertyValue(key)+"')");

            sb.AppendLine().Append("Begin");

            sb.AppendLine().Append(BuildUpdateCom());

            sb.AppendLine().Append("End");

            sb.AppendLine().Append("Else");

            sb.AppendLine().Append("Begin");

            sb.AppendLine().Append( BuildInsertCom());

            sb.AppendLine().Append("End");

            return sb.ToString();

        }