求详细解释。
CREATE PROCEDURE [dbo].[Dv_GetRecordFromPage]@tableName nvarchar(100),-- 表名@fldSort nvarchar(100) = 'dateandtime',-- 排序字段@pageSize int = 30,-- 每页大小 @page int = 1 ,-- 第几页@Sort bit = 1,-- 排序,@Sort=0 升序@Sort=1 降序@ConditionStr nvarchar(1000),--查询条件@fldName nvarchar(2000) = '*'--查询字段ASDeclare @strTmp nvarchar(4000)Declare @sqlSort nvarchar(20)Declare @Compare varchar(1)Declare @Compare1 nvarchar(20)Declare @intCounts intDECLARE @var_Splitvalue varchar(5000)DECLARE @nRet intIf @Sort=0Begin Set @sqlSort ='DESC' Set @Compare = '<' Set @Compare1='Min' EndElse Begin Set @sqlSort ='ASC' Set @Compare = '>' Set @Compare1='Max'EndIf @page >1 begin SELECT @intCounts=(@Page-1) * @pagesize SET @strTmp='SELECT @var_Splitvalue ='+@Compare1+'(' + @fldSort + ') FROM (Select Top '+CAST(@intCounts as nvarchar)+' ' + @fldSort + ' From '+@tableName+' where '+@ConditionStr+' order BY ' + @fldSort + ' ' + @sqlSort+') as t' EXEC sp_executesql @strTmp,N'@var_Splitvalue varchar(5000) output',@var_Splitvalue output SET ROWCOUNT @pagesize SET @strTmp='SELECT '+ @fldName +' FROM '+@tableName+' where '+ @ConditionStr +' AND ' + @fldSort+ @Compare + ' @2 '+' '+' ORDER BY ' + @fldSort + ' ' + @sqlSort EXEC sp_executesql @strTmp,N'@2 varchar(5000)',@2=@var_Splitvalue EndElse begin SET ROWCOUNT @pagesize SET @strTmp='SELECT '+ @fldName +' FROM '+@tableName+' where ' +@ConditionStr+' ORDER BY ' + @fldSort + ' ' + @sqlSort EXEC sp_executesql @strTmp end