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标题: 浅述asp.net海量分页数据存储过程 [打印本页]

作者: abcdef133 时间: 2011-5-4 15:48
标题: 浅述asp.net海量分页数据存储过程
数据分页是Web应用程序开发中经常使用的一种技术，也是提高Web数据访问性能的主要手段。本文结合ASP.NET，详细给出了两种ASP.NET海量分页数据存储的技术。

存储过程1

CREATE PROCEDURE pagination
@tblName varchar(255), -- 表名
@strGetFields varchar(1000) = '*', -- 需要返回的列
@fldName varchar(255)='', -- 排序的字段名
@PageSize int , -- 页尺寸
@PageIndex int, -- 页码
@doCount bit , -- 返回记录总数, 非 0 值则返回
@OrderType bit , -- 设置排序类型, 非 0 值则降序
@strWhere varchar(1500) = '' -- 查询条件 (注意: 不要加 where)
AS
declare @strSQL varchar(5000) -- 主语句
declare @strTmp varchar(110) -- 临时变量
declare @strOrder varchar(400) -- 排序类型

if @doCount != 0
begin
if @strWhere !=''
set @strSQL = "select count(*) as Total from [" + @tblName + "] where "+@strWhere
else
set @strSQL = "select count(*) as Total from [" + @tblName + "]"
end
--以上代码的意思是如果@doCount传递过来的不是0，就执行总数统计。以下的所有代码都是@doCount为0的情况
else
begin

if @OrderType != 0
begin
set @strTmp = "<(select min"
set @strOrder = " order by [" + @fldName +"] desc"
--如果@OrderType不是0，就执行降序，这句很重要！
end
else
begin
set @strTmp = ">(select max"
set @strOrder = " order by [" + @fldName +"] asc"
end

if @PageIndex = 1
begin
if @strWhere != ''
set @strSQL = "select top " + str(@PageSize) +" "+@strGetFields+ " from [" + @tblName + "] where " + @strWhere + " " + @strOrder
else
set @strSQL = "select top " + str(@PageSize) +" "+@strGetFields+ " from ["+ @tblName + "] "+ @strOrder
--如果是第一页就执行以上代码，这样会加快执行速度
end
else
begin
--以下代码赋予了@strSQL以真正执行的SQL代码
set @strSQL = "select top " + str(@PageSize) +" "+@strGetFields+ " from ["
+ @tblName + "] where [" + @fldName + "]" + @strTmp + "(["+ @fldName + "]) from (select top " + str((@PageIndex-1)*@PageSize) + " ["+ @fldName + "] from [" + @tblName + "]" + @strOrder + ") as tblTmp)"+ @strOrder

if @strWhere != ''
set @strSQL = "select top " + str(@PageSize) +" "+@strGetFields+ " from ["
+ @tblName + "] where [" + @fldName + "]" + @strTmp + "(["
+ @fldName + "]) from (select top " + str((@PageIndex-1)*@PageSize) + " ["
+ @fldName + "] from [" + @tblName + "] where " + @strWhere + " "
+ @strOrder + ") as tblTmp) and " + @strWhere + " " + @strOrder
end
end
exec (@strSQL)
GO

调用的程序（为了通用性，我写了一个方法，大家可以提意见，也可以对其进行修改，多多交换意见，共同进步）
  private static DataSet GetCustomersData(string tblName, string strGetFields,string fldName, int PageSize, int PageIndex, int doCount, int OrderType, string strWhere)
{
string connString = ConfigurationSettings.AppSettings["connstr"];
SqlConnection conn = new SqlConnection(connString);
SqlCommand comm = new SqlCommand("pagination3", conn);

comm.Parameters.Add(new SqlParameter("@tblName", SqlDbType.VarChar));//表名
comm.Parameters[0].Value =tblName ;
comm.Parameters.Add(new SqlParameter("@strGetFields", SqlDbType.VarChar));//返回的列
comm.Parameters[1].Value = strGetFields;
comm.Parameters.Add(new SqlParameter("@fldName", SqlDbType.VarChar));//排序的字段名
comm.Parameters[2].Value = fldName;
comm.Parameters.Add(new SqlParameter("@PageSize",SqlDbType.Int));//页尺寸
comm.Parameters[3].Value = PageSize;
comm.Parameters.Add(new SqlParameter("@PageIndex", SqlDbType.Int));//页码
comm.Parameters[4].Value = PageIndex;
comm.Parameters.Add(new SqlParameter("@doCount", SqlDbType.Int));//是否返回记录总数，0为不返回，1为返回
comm.Parameters[5].Value = doCount;
comm.Parameters.Add(new SqlParameter("@OrderType", SqlDbType.Int));//设置排序类型，0为升序，非0为降序
comm.Parameters[6].Value = OrderType;
comm.Parameters.Add(new SqlParameter("@strWhere", SqlDbType.VarChar));//where语句
comm.Parameters[7].Value = strWhere;
comm.CommandType = CommandType.StoredProcedure;
SqlDataAdapter dataAdapter = new SqlDataAdapter(comm);
DataSet ds = new DataSet();
dataAdapter.Fill(ds);
return ds;
}

存储过程2

CREATE PROCEDURE [dbo].[GetRecordFromPage]
@SelectList          VARCHAR(2000), --欲选择字段列表
@TableSource       VARCHAR(100), --表名或视图表
@SearchCondition VARCHAR(2000), --查询条件
@OrderExpression VARCHAR(1000), --排序表达式
@PageIndex          INT = 1,       --页号,从0开始
@PageSize          INT = 10       --页尺寸
AS
BEGIN
IF @SelectList IS NULL OR LTRIM(RTRIM(@SelectList)) = ''
BEGIN
      SET @SelectList = '*'
END
PRINT @SelectList

SET @SearchCondition = ISNULL(@SearchCondition,'')
SET @SearchCondition = LTRIM(RTRIM(@SearchCondition))
IF @SearchCondition <> ''
BEGIN
      IF UPPER(SUBSTRING(@SearchCondition,1,5)) <> 'WHERE'
      BEGIN
         SET @SearchCondition = 'WHERE ' + @SearchCondition
      END
END
PRINT @SearchCondition

SET @OrderExpression = ISNULL(@OrderExpression,'')
SET @OrderExpression = LTRIM(RTRIM(@OrderExpression))
IF @OrderExpression <> ''
BEGIN
      IF UPPER(SUBSTRING(@OrderExpression,1,5)) <> 'WHERE'
      BEGIN
         SET @OrderExpression = 'ORDER BY ' + @OrderExpression
      END
END
PRINT @OrderExpression

IF @PageIndex IS NULL OR @PageIndex < 1
BEGIN
      SET @PageIndex = 1
END
PRINT @PageIndex
IF @PageSize IS NULL OR @PageSize < 1
BEGIN
      SET @PageSize = 10
END
PRINT  @PageSize

DECLARE @SqlQuery VARCHAR(4000)

SET @SqlQuery='SELECT '+@SelectList+',RowNumber
FROM
      (SELECT ' + @SelectList + ',ROW_NUMBER() OVER( '+ @OrderExpression +') AS RowNumber
      FROM '+@TableSource+' '+ @SearchCondition +') AS RowNumberTableSource
WHERE RowNumber BETWEEN ' + CAST(((@PageIndex - 1)* @PageSize+1) AS VARCHAR)
+ ' AND ' +
CAST((@PageIndex * @PageSize) AS VARCHAR)
-- ORDER BY ' + @OrderExpression
PRINT @SqlQuery
SET NOCOUNT ON
EXECUTE(@SqlQuery)
SET NOCOUNT OFF

RETURN @@RowCount
END

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