帮我解释一下分页存储过程

分页存储过程：
 
用我是基本会用，想把SQL语句也弄清楚，我没有专门学过SQL
语句，呵呵 其中有一些是对字符串的操作吧？我对过网络查找
搞明白一部分

其中的这一段我没看明白：
    DECLARE @type varchar(50)
    DECLARE @prec int
    SELECT @type= , @prec= ec
    FROM sysobjects o 
    JOIN syscolumns c on  = 
    JOIN systypes t on c.xusertype=t.xusertype
    WHERE   = @SortTable AND   = @SortName
    IF CHARINDEX('char', @type) > 0
    SET @type = @type + '(' + CAST(@prec AS varchar) + ')'
   
    DECLARE @TopRows INT  --下一页的第一条记录数
    SET @TopRows = @PageSize * @CurrentPage + 1
    print @TopRows
    print @Operator
我传进去的参数如下：
@TableNames = News left join Newskinds on  wsKindId = Newskinds.KindId left join users on  erId =  erId
@PrimaryKey = News.NewsId
@Fields = News.NewsId, wsTitle,news.pubDate,Newskinds.KindName, erName
@PageSize = 2
@CurrentPage CurrentPage - 1
@Filter = strWhere = newsTitle like '%国际%'      
@Group 分组为空
@Order = News.NewsId DESC 
@RecordCount 

根据传进去的参数和字符串我组合出如下SQL语句，好像有点不对，请高手给我更正一下：
DECLARE @SortColumnBegin ' + @type + '
SET ROWCOUNT 5
SELECT News.NewsId FROM 
News left join Newskinds on  wsKindId = Newskinds.KindId left join users on  erId =  erId
WHERE newsTitle like '%国际%' ORDER BY News.NewsId DESC
SET ROWCOUNT 2
SELECT News.NewsId, wsTitle,news.pubDate,Newskinds.KindName, erName
FROM News left join Newskinds on  wsKindId = Newskinds.KindId left join users on  erId =  erId 
WHERE newsTitle like '%国际%' AND News.NewsId <= '@SortColumnBegin '  ORDER BY  News.NewsId DESC

全部

贯***

回答