C#OleDbDataReader.Read()耗时过高的解决办法

Question

读取Access中一列的数据，大约700条需要4s-5s才完成，如何解决读取速度过慢的问题？

         /// <summary>
        /// 在MDB中读取数据
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="queryString">要执行的SQL语句</param>
        /// <param name="columnName">要查询的列名</param>
        /// <returns>返回一个集合为该列的所有值</returns>
        public static ArrayList ReadDate(string connectionString, string queryString, string columnName)
        {
            ArrayList list = new ArrayList();
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                OleDbCommand command = new OleDbCommand(queryString, connection);
                connection.Open();
                OleDbDataReader reader = command.ExecuteReader();
                while (reader.Read())
                {
                    list.Add(reader[columnName]);
                }
                reader.Close();
            }
            return list;
        }

Answer 1

使用DataRead方法之前，将数据库打开！