2分法-通用存储过程分页(top max模式)版本(性能相对之前的not in版本极大提高)

--/*-----存储过程 分页处理 孙伟 2005-03-28创建 -------*/
--
/*----- 对数据进行了2分处理使查询前半部分数据与查询后半部分数据性能相同 -------*/
--
/*-----存储过程 分页处理 孙伟 2005-04-21修改 添加Distinct查询功能-------*/
--
/*-----存储过程 分页处理 孙伟 2005-05-18修改 多字段排序规则问题-------*/
--
/*-----存储过程 分页处理 孙伟 2005-06-15修改 多字段排序修改-------*/
--
/*-----存储过程 分页处理 孙伟 2005-12-13修改 修改数据分页方式为top max模式 性能有极大提高-------*/
--
/*-----缺点:相对之前的not in版本主键只能是整型字段,如主键为GUID类型请使用not in 模式的版本-------*/
CREATE PROCEDURE dbo.proc_ListPageInt
(
@tblName nvarchar(200), ----要显示的表或多个表的连接
@fldName nvarchar(500) = '*', ----要显示的字段列表
@pageSize int = 10, ----每页显示的记录个数
@page int = 1, ----要显示那一页的记录
@pageCount int = 1 output, ----查询结果分页后的总页数
@Counts int = 1 output, ----查询到的记录数
@fldSort nvarchar(200) = null, ----排序字段列表或条件
@Sort bit = 0, ----排序方法,0为升序,1为降序(如果是多字段排列Sort指代最后一个排序字段的排列顺序(最后一个排序字段不加排序标记)--程序传参如:' SortA Asc,SortB Desc,SortC ')
@strCondition nvarchar(1000) = null, ----查询条件,不需where
@ID nvarchar(150), ----主表的主键
@Dist bit = 0 ----是否添加查询字段的 DISTINCT 默认0不添加/1添加
)
AS
SET NOCOUNT ON
Declare @sqlTmp nvarchar(1000) ----存放动态生成的SQL语句
Declare @strTmp nvarchar(1000) ----存放取得查询结果总数的查询语句
Declare @strID nvarchar(1000) ----存放取得查询开头或结尾ID的查询语句

Declare @strSortType nvarchar(10) ----数据排序规则A
Declare @strFSortType nvarchar(10) ----数据排序规则B

Declare @SqlSelect nvarchar(50) ----对含有DISTINCT的查询进行SQL构造
Declare @SqlCounts nvarchar(50) ----对含有DISTINCT的总数查询进行SQL构造


if @Dist = 0
begin
set @SqlSelect = 'select '
set @SqlCounts = 'Count(*)'
end
else
begin
set @SqlSelect = 'select distinct '
set @SqlCounts = 'Count(DISTINCT '+@ID+')'
end


if @Sort=0
begin
set @strFSortType=' ASC '
set @strSortType=' DESC '
end
else
begin
set @strFSortType=' DESC '
set @strSortType=' ASC '
end



--------生成查询语句--------
--
此处@strTmp为取得查询结果数量的语句
if @strCondition is null or @strCondition='' --没有设置显示条件
begin
set @sqlTmp = @fldName + ' From ' + @tblName
set @strTmp = @SqlSelect+' @Counts='+@SqlCounts+' FROM '+@tblName
set @strID = ' From ' + @tblName
end
else
begin
set @sqlTmp = + @fldName + 'From ' + @tblName + ' where (1>0) ' + @strCondition
set @strTmp = @SqlSelect+' @Counts='+@SqlCounts+' FROM '+@tblName + ' where (1>0) ' + @strCondition
set @strID = ' From ' + @tblName + ' where (1>0) ' + @strCondition
end

----取得查询结果总数量-----
exec sp_executesql @strTmp,N'@Counts int out ',@Counts out
declare @tmpCounts int
if @Counts = 0
set @tmpCounts = 1
else
set @tmpCounts = @Counts

--取得分页总数
set @pageCount=(@tmpCounts+@pageSize-1)/@pageSize

/**当前页大于总页数 取最后一页**/
if @page>@pageCount
set @page=@pageCount

--/*-----数据分页2分处理-------*/
declare @pageIndex int --总数/页大小
declare @lastcount int --总数%页大小

set @pageIndex = @tmpCounts/@pageSize
set @lastcount = @tmpCounts%@pageSize
if @lastcount > 0
set @pageIndex = @pageIndex + 1
else
set @lastcount = @pagesize

--//***显示分页
if @strCondition is null or @strCondition='' --没有设置显示条件
begin
if @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2 --前半部分数据处理
begin
if @page=1
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' order by '+ @fldSort +''+ @strFSortType
else
begin
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' where '+@ID+' <(select min('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +''+ @ID +' from '+@tblName
+' order by '+ @fldSort +''+ @strFSortType+') AS TBMinID)'
+' order by '+ @fldSort +''+ @strFSortType
end
end
else
begin
set @page = @pageIndex-@page+1 --后半部分数据处理
if @page <= 1 --最后一页数据显示
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@lastcount as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' order by '+ @fldSort +''+ @strSortType+') AS TempTB'+' order by '+ @fldSort +''+ @strFSortType
else
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' where '+@ID+' >(select max('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +''+ @ID +' from '+@tblName
+' order by '+ @fldSort +''+ @strSortType+') AS TBMaxID)'
+' order by '+ @fldSort +''+ @strSortType+') AS TempTB'+' order by '+ @fldSort +''+ @strFSortType
end
end

else --有查询条件
begin
if @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2 --前半部分数据处理
begin
if @page=1
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' where 1=1 ' + @strCondition + ' order by '+ @fldSort +''+ @strFSortType
else
begin
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' where '+@ID+' <(select min('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +''+ @ID +' from '+@tblName
+' where (1=1) ' + @strCondition +' order by '+ @fldSort +''+ @strFSortType+') AS TBMinID)'
+''+ @strCondition +' order by '+ @fldSort +''+ @strFSortType
end
end
else
begin
set @page = @pageIndex-@page+1 --后半部分数据处理
if @page <= 1 --最后一页数据显示
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@lastcount as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' where (1=1) '+ @strCondition +' order by '+ @fldSort +''+ @strSortType+') AS TempTB'+' order by '+ @fldSort +''+ @strFSortType
else
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+''+ @fldName+' from '+@tblName
+' where '+@ID+' >(select max('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +''+ @ID +' from '+@tblName
+' where (1=1) '+ @strCondition +' order by '+ @fldSort +''+ @strSortType+') AS TBMaxID)'
+''+ @strCondition+' order by '+ @fldSort +''+ @strSortType+') AS TempTB'+' order by '+ @fldSort +''+ @strFSortType
end
end

------返回查询结果-----
exec sp_executesql @strTmp
--print @strTmp
SET NOCOUNT OFF
GO

调用方法列子:

///<summary>
/// 通用分页数据读取函数
/// 注意:在函数调用外部打开和关闭连接,以及关闭数据读取器
///</summary>
///<param name="comm">SqlCommand对象</param>
///<param name="_tblName">查询的表/表联合</param>
///<param name="_fldName">要查询的字段名</param>
///<param name="_pageSize">每页数据大小</param>
///<param name="_page">当前第几页</param>
///<param name="_fldSort">排序字段</param>
///<param name="_Sort">排序顺序0降序1升序</param>
///<param name="_strCondition">过滤条件</param>
///<param name="_ID">主表主键</param>
///<param name="_dr">返回的SqlDataReader ref</param>
public static void CutPageData(SqlConnection conn, ref SqlCommand comm, string _tblName, string _fldName, int _pageSize, int _page, string _fldSort, int _Sort, string _strCondition, string _ID, ref SqlDataReader _dr)
{
//注意:在函数调用外部打开和关闭连接,以及关闭数据读取器
//comm = new SqlCommand("proc_ListPage",conn);
//comm.CommandType = CommandType.StoredProcedure;
comm.Parameters.Add("@tblName", SqlDbType.NVarChar, 200);
comm.Parameters["@tblName"].Value = _tblName;
comm.Parameters.Add("@fldName", SqlDbType.NVarChar, 500);
comm.Parameters["@fldName"].Value = _fldName;
comm.Parameters.Add("@pageSize", SqlDbType.Int);
comm.Parameters["@pageSize"].Value = _pageSize;
comm.Parameters.Add("@page", SqlDbType.Int);
comm.Parameters["@page"].Value = _page;
comm.Parameters.Add("@fldSort", SqlDbType.NVarChar, 200);
comm.Parameters["@fldSort"].Value = _fldSort;
comm.Parameters.Add("@Sort", SqlDbType.Bit);
comm.Parameters["@Sort"].Value = _Sort;
comm.Parameters.Add("@strCondition", SqlDbType.NVarChar, 1000);
comm.Parameters["@strCondition"].Value = _strCondition;
comm.Parameters.Add("@ID", SqlDbType.NVarChar, 150);
comm.Parameters["@ID"].Value = _ID;
comm.Parameters.Add("@Counts", SqlDbType.Int, 0);
comm.Parameters["@Counts"].Direction = ParameterDirection.Output;
comm.Parameters.Add("@pageCount", SqlDbType.Int, 0);
comm.Parameters["@pageCount"].Direction = ParameterDirection.Output;

_dr = comm.ExecuteReader();
}

调用例如:
CutPageData(conn, ref comm, "VOX_CDSinger", "id, cdsinger, cdsingertype, area, cdsingerreadme", 15, page, "id", 1, strFilter, "id", ref dr);
对应说明:
CutPageData(数据连接对象, ref Sqlcommand对象, "需要表或视图名称", "要查询的字段", 每页读取数据条数, 当前页, "排序字段可多字段如(addtime desc, visitcounts注意这里最后一个字段不加desc或asc 最后一个字段对应于后面的排序规则)", 排序方式(1 desc 0 asc), where条件(这里不再添加where条件添加如:' and visitcounts>100'), 表主键, ref 返回的SqlDataReader对象);

这里的调用同样适用于之前的not in版本.

原文:http://www.cnblogs.com/hertcloud/archive/2005/12/21/301327.html

posted @ 2011-11-20 09:39  coxsoft  阅读(205)  评论(0编辑  收藏  举报