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();
        }