一个高效的数据分页的存储过程 可以轻松应付百万数据

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-- 获取指定页的数据
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 = 10, -- 页尺寸
    @PageIndex int = 1, -- 页码
    @doCount bit = 0, -- 返回记录总数, 非 0 值则返回
    @OrderType bit = 0, -- 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

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