前面一篇随笔,我提到了Sql Server 2000的自定义分页,但是在sql server 2000中,要实现显示某一页,就返回那一页数据的效果的方法实在不尽人意.网上很多通用的分页存储过程,但看着就头大.如果使用我前面提到的使用in,not in,top来进行返回特定页,特殊的限制又会
前面一篇随笔,我提到了Sql Server 2000的自定义分页,但是在sql server 2000中,要实现显示某一页,就返回那一页数据的效果的方法实在不尽人意.网上很多通用的分页存储过程,但看着就头大.如果使用我前面提到的使用in,not in,top来进行返回特定页,特殊的限制又会比较多(比如ID要递增).现在Sql Server 2005中提供了一个函数ROW_NUMBER(),可以使自定义分页变得简单许多.
我们先来看看ROW_NUMBER()是干什么的.执行下面这段SQL语句:
SELECT [ReportID],[UserName], [ReportID],
[TimeStart], [TimeEnd],ROW_NUMBER() OVER (ORDER BY ReportID) AS RowNo
FROM [ExecutionLog]
执行结果如下图所示:
很简单,ROW_NUMBER() 就是生成一个顺序的行号,而他生成顺序的标准,就是后面紧跟的OVER(ORDER BY ReportID).现在,你看到了自定义分页的影子了吗?:)下面,我们看看怎么具体应用这个RowNo进行分页.
现在,假设我每一页的数据是10条,我们就可以使用如下所示的SQL语句返回指定页的数据:
@"
SELECT TOP 10 *
FROM
(
SELECT top 10 [InstanceName], [UserName], [ReportID],
[TimeStart], [TimeEnd],ROW_NUMBER() OVER (ORDER BY ReportID) AS RowNo
FROM [ExecutionLog]
) AS A
WHERE RowNo > " + pageIndex*10
pageIndex就是我们需要数据的页数.很简单,不是吗?并且,这种方式几乎没有什么限制,因为他相当于对于任何检索,都生成了一个新的排序列.我们就可以使用该列进行自定义分页.
----2005.11.26 11:43 星期六

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