ACCESS的高效分页语句

 程序代码string strSql = " Select P.ProductID,P.ProClassID,P.ProductName,P.ProFlag,P.DateTime,P.ProductImage,C.ProClassName,C.ProClassKey,C.ProClassDes FROM ProductInfo P  " +                                " LEFT JOIN ProClass C ON P.ProClassID=C.ProClassID ";                string strShow = " ProductID,ProductName,DateTime,ProductImage,ProFlag,ProClassName,ProClassKey,ProClassDes ";                return ClassFile.AccessHelper.ExecutePager(PageIndex, PageSize, "ProductID", strShow, strSql, strWhere, " ProductID DESC ", out PageCount, out RecordCount);  程序代码/// <summary>        /// 分页使用        /// </summary>        /// <param name="query"></param>        /// <param name="passCount"></param>        /// <returns></returns>        private static string recordID(string query, int passCount)        {            using (OleDbConnection m_Conn = new OleDbConnection(ConnectionString))            {                m_Conn.Open();                OleDbCommand cmd = new OleDbCommand(query, m_Conn);                string result = string.Empty;                using (OleDbDataReader dr = cmd.ExecuteReader())                {                    while (dr.Read())                    {                        if (passCount < 1)                        {                            result += "," + dr.GetInt32(0);                        }                        passCount--;                    }                }                m_Conn.Close();                m_Conn.Dispose();                return result.Substring(1);            }        }        /// <summary>        /// ACCESS高效分页        /// </summary>        /// <param name="pageIndex">当前页码</param>        /// <param name="pageSize">分页容量</param>        /// <param name="strKey">主键</param>        /// <param name="showString">显示的字段</param>        /// <param name="queryString">查询字符串，支持联合查询</param>        /// <param name="whereString">查询条件，若有条件限制则必须以where 开头</param>        /// <param name="orderString">排序规则</param>        /// <param name="pageCount">传出参数：总页数统计</param>        /// <param name="recordCount">传出参数：总记录统计</param>        /// <returns>装载记录的DataTable</returns>        public static DataTable ExecutePager(int pageIndex, int pageSize, string strKey,string showString, string queryString, string whereString, string orderString, out int pageCount, out int recordCount)        {            if (pageIndex < 1) pageIndex = 1;            if (pageSize < 1) pageSize = 10;            if (string.IsNullOrEmpty(showString)) showString = "*";            if (string.IsNullOrEmpty(orderString)) orderString = strKey+" asc ";            using (OleDbConnection m_Conn = new OleDbConnection(ConnectionString))            {                m_Conn.Open();                string myVw = string.Format(" ( {0} ) tempVw ", queryString);                OleDbCommand cmdCount = new OleDbCommand(string.Format(" select count(*) as recordCount from {0} {1}", myVw, whereString), m_Conn);                recordCount = Convert.ToInt32(cmdCount.ExecuteScalar());                if ((recordCount % pageSize) > 0)                    pageCount = recordCount / pageSize + 1;                else                    pageCount = recordCount / pageSize;                OleDbCommand cmdRecord;                if (pageIndex == 1)//第一页                {                    cmdRecord = new OleDbCommand(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageSize, showString, myVw, whereString, orderString), m_Conn);                }                else if (pageIndex > pageCount)//超出总页数                {                    cmdRecord = new OleDbCommand(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageSize, showString, myVw, "where 1=2", orderString), m_Conn);                }                else                {                    int pageLowerBound = pageSize * pageIndex;                    int pageUpperBound = pageLowerBound - pageSize;                    string recordIDs = recordID(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageLowerBound, strKey, myVw, whereString, orderString), pageUpperBound);                    cmdRecord = new OleDbCommand(string.Format("select {0} from {1} where {2} in ({3}) order by {4} ", showString, myVw,strKey, recordIDs, orderString), m_Conn);                }                OleDbDataAdapter dataAdapter = new OleDbDataAdapter(cmdRecord);                DataTable dt = new DataTable();                dataAdapter.Fill(dt);                m_Conn.Close();                m_Conn.Dispose();            return dt;            }        }