/*
数据库分页存储过程，支持倒序和升序
参数说明：
  @tablename：为搜索表名
  @tablefield：为表的字段，约定为表的主键,
  @where：为搜索表名，要显示所有记录请设为"1=1"
  @orderby：为搜索结果排序，如order by id desc
  @fieldlist：为字段列表，如userid, username
  @curpage：当前页码
  @page_record：每页记录条数
  @Sort：排序标识（如果是倒序排，参数值为desc，为升序，参数值为asc，跟orderby参数是对应的）
结果： 返回表tablename中满足条件where的第curpage页的page_record条记录，结果按orderby排序
*/
CREATE PROCEDURE proc_CommonPaging

@tablename varchar(100),
@tablefield varchar(20),
@where varchar(5000),
@orderby varchar(500),
@fieldlist varchar(1000),
@curpage int,
@page_record int,
@sort varchar(8)

AS

BEGIN

  DECLARE @cmd varchar(8000)
  DECLARE @uprecord int
  DECLARE @Op varchar(2) -- 操作符
  DECLARE @max_min varchar(4) -- 最大/最小计算

  SET @op = '<'
  SET @max_min = 'MIN'
  IF @sort = 'asc'
      BEGIN
    SET @Op = '>'
            SET @max_min = 'MAX'
      END

  SET @uprecord=@curpage * @page_record
 
  IF @curpage = 0
      SET @cmd = 'SELECT TOP '+cast(@page_record AS NVARCHAR)+' '+@fieldlist+' FROM '+@tablename+' WHERE '+@where+' '+@orderby
  ELSE
    SET @cmd = 'SELECT TOP '+cast(@page_record AS NVARCHAR)+' '+@fieldlist+' FROM '+@tablename+' WHERE '+@where+' AND '+@tablefield+'
    '+@op+' (SELECT '+@max_min+'('+@tablefield+')  FROM (SELECT TOP  '+cast(@uprecord AS NVARCHAR)+' '+@tablefield+' FROM '+@tablename+' WHERE
    '+@where+' '+@orderby+') AS TmpTbl ) AND '+@where+' '+@orderby

  SET @cmd = @cmd + '; SELECT COUNT(*) FROM '+@tablename+' WHERE '+@where

  EXEC(@cmd)
  PRINT(@cmd)

END
GO