/// <summary>
        /// 解析 select 语句
        /// </summary>
        /// <param name="selectClause"></param>
        /// <param name="queryModel"></param>
        public override void VisitSelectClause( SelectClause selectClause, QueryModel queryModel )
        {
            MySqlSelectClauseVisitor visitor = new MySqlSelectClauseVisitor( this.parameterAggregator );

            string selectParts = visitor.Translate( selectClause.Selector );

            queryPartsAggregator.SelectPart = selectParts;

            base.VisitSelectClause( selectClause, queryModel );
        }
        /// <summary>
        /// 解析 select 语句
        /// </summary>
        /// <param name="selectClause"></param>
        /// <param name="queryModel"></param>
        public override void VisitSelectClause( SelectClause selectClause, QueryModel queryModel )
        {
            MySqlSelectPartsCommandBuilder selectBuilder = new MySqlSelectPartsCommandBuilder();

            MySqlSelectClauseVisitor visitor = new MySqlSelectClauseVisitor();

            visitor.Translate( selectClause.Selector, selectBuilder );

            commandBuilder.SelectPart = selectBuilder.ToString();

            base.VisitSelectClause( selectClause, queryModel );
        }