PB程序员面试题目:数据窗口的4个缓冲区是什么?
它们的作用和区别是什么?
我没答出来....:(
问题点数：0、回复次数：7Top
1 楼zhengshouquan（一叶知秋）回复于 2004-12-02 16:48:41 得分 0
主,过滤,删除，预备缓冲区Top
2 楼airfont（草原劣马）回复于 2004-12-02 16:52:45 得分 0
应该是这四人吧.Top
3 楼li_d_s（鄙视那些不懂Java却跑来乱骂的人，.NET没啥了不起）回复于 2004-12-02 17:25:10 得分 0
Description
Values for specifying the DataWindow buffer containing the rows you want to access.
Used in many DataWindow methods that access data.
Values
PowerBuilder enumerated value Web DataWindow Numeric value Meaning
Primary! Primary 0 The data in the primary buffer, meaning data that has not been deleted or filtered out. (Default value when argument is optional.)
Delete! Delete 1 Data in the delete buffer, meaning data that has been deleted from the DataWindow but has not been committed to the database.
Filter! Filter 2 Data in the filter buffer, meaning data that has been removed from view.
Web DataWindow In Web DataWindow methods, you can use a string value with or without the exclamation point for a DataWindow buffer. For example, you could use
Primary or Primary! to specify the primary buffer.Top
4 楼37350792（嵇幼雄-不算高手）回复于 2004-12-02 19:13:14 得分 0
!primary
!deleted
!filter
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5 楼luotitan（泰坦）回复于 2004-12-02 19:18:05 得分 0
original原始缓冲区Top
6 楼handycyw（xmccc）回复于 2004-12-02 19:21:12 得分 0
original! : retrieve后存放数据
primary! ：当前数据
delete! : 删除的未update前的数据
filter! : 过滤掉的数据Top
7 楼mnsiii（水流花谢两无情）回复于 2004-12-02 21:52:27 得分 0
具体是这样的orginal!应该是原始缓冲区，存放原始的数据
primary！主缓冲区，存放当前的数据
delete!删除缓冲区，存放删除的数据
filter! : 存放过滤掉的数据
在update的时候，根据缓冲区数据与orginal中的数据比较，来生成sql语句。
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