关系模型和XML [英] Relational Model and XML
问题描述
这个问题困扰了我一段时间。很多人
似乎在思考 XML是数据问题的王者，我听说下一版本的SQL Server将具有强大的XML风格，
同时，我似乎得到的印象是，大量
硬核关系模型专家似乎并没有对
XML留下深刻印象（这个额外层的技术价值似乎有限而
商业价值可能很大，例如，更多软件工作，b
更多磁盘空间要求等等）。你对此有何看法？
一般性或细节，欢迎所有。一个具体的问题是，如何使用XML来补充关系模型？
谢谢。
Hi,
This question has been bothering me for some time. A lot of people
seem to "think" XML is the king of data problems, and I''ve heard that
next version of SQL Server is going to have a strong XML flavor,
meantime, I seem to get the impression that a large number of
hard-core relational model gurus do not seem to be that impressed with
XML (technical value of this extra layer seems to be limited while
business value might be substantial for instance, more software work,
more disk space requirement etc. etc.). What''s your take on this?
Generality or specifics, all welcome. One specific question is, how
can XML supplement relational model?
Thanks.
推荐答案
Doug Baroter（qw********@boxfrog.com）写道：
Doug Baroter (qw********@boxfrog.com) writes:
这个问题困扰了我一段时间。很多人似乎都在思考 XML是数据问题的王者，我听说下一版本的SQL Server将具有强大的XML风格，同时，我似乎得到了大量的
核心关系模型大师似乎没有对XML印象深刻（这个额外层的技术价值似乎有限，而商业价值可能很大，例如，更多的软件工作，
更多磁盘空间要求等。你对此有何看法？
一般性或细节，欢迎所有人。一个具体问题是，XML如何能够补充关系模型？
This question has been bothering me for some time. A lot of people
seem to "think" XML is the king of data problems, and I''ve heard that
next version of SQL Server is going to have a strong XML flavor,
meantime, I seem to get the impression that a large number of
hard-core relational model gurus do not seem to be that impressed with
XML (technical value of this extra layer seems to be limited while
business value might be substantial for instance, more software work,
more disk space requirement etc. etc.). What''s your take on this?
Generality or specifics, all welcome. One specific question is, how
can XML supplement relational model?
一个广泛的问题，但XML似乎有它的位置。 XML
真正有意义的是数据交换。一个数据库是一堆
表，但它们只是坐在一个地方，而不是四处旅行。但是
他们的数据呢。虽然XML可能体积庞大且开销很大，但它具有很好的属性，它定义了一个标准框架
，您可以将数据放入其中。
这是一个很好的附带好处，就是使用XML我们突然得到了一个将大量数据插入SQL Server的方法
只需在网络上进行一次往返：发送XML文档，
然后说INSERT ... OPENXML。
然后在Yukon他们正在接受它更进一步，添加Xquery，
你有系统函数返回XML数据等。也许MS是
，它有点太过分了，但XML仍然存在。
-
Erland Sommarskog，SQL Server MVP，所以**** @ algonet。 se
SQL Server SP3联机丛书
http://www.microsoft.com/sql/techinf...2000/books.asp
>>你对此有何看法？一般性或细节，都欢迎。 <
在XML领域有很多研究工作（特别是SIGMOD上的论文，DBPL等关于XML的建议） ，但我不确定是否有任何建议将XML视为数据模型的替代品。
供应商为消费者提供他们的要求，不是什么是经验性的
和/或有原则的。当竞争和客户保留决定因素时，通常是过时的技术会在新的术语下以微小的b $ b变化复苏。这就是所有以利润为基础的行业，包括IT行业的工作方式。
>> What''s your take on this? Generality or specifics, all welcome. <<
There is lot of research work (esp. papers at SIGMOD, DBPL etc on XML
suggests ) going on in the field of XML, but I am not sure if anything
positive has been established to consider XML as a data model alternative.
Vendors provide the consumers what they ask for, not what is empirical
and/or principled. When competition and customer retention become deciding
factors, often technologies that are obsolete, gets revived with minor
changes, under new terminologies. That is how the all profit-based
industries, including the IT industry, work.
一个具体的问题是， XML如何补充关系模型？ <
One specific question is, how can XML supplement relational model? <<
数据管理的基本原理清楚地告诉我，关系模型
不需要XML补充;任何相关的。然而，令人困惑的是，关于这个主题的很多新闻文章都充斥着夸张和技术的夸张和techno-tyros，他们无法区分数据交换
$ b来自数据模型的$ b技术，认为XML将改变世界
一夜之间。
-
- Anith
（请仅回复新闻组）
The fundamentals of data management clearly tell me that Relational model
needs no supplementation by "XML" for anything relevant. However, it is
confusing that so many press articles on the topic are filled with
exaggerations and techno-tyros, who cannot distinguish a data exchange
technology from a data model, opining about XML going to change the world
overnight.
--
- Anith
( Please reply to newsgroups only )
是的，这真的很好，因为用户仍然只需要
执行存储过程的权限。 :)
实际上我发现OPENXML有问题，我已经意味着
发布了。我们有传统的平面文件系统（我们当然希望用
替换它们，但我们不能抓住它们的手指和宾果它已经完成了）
使用相当于char字段的各种数字出现的
标识符，例如我们的合同号。例如，遗留系统中的
合约编号字段是10个字符，但是现在我们仍然在700000左右，所以它显示了因为四个空格跟随
六个数字字符。 OPENXML吃掉所有领先的空间
（在你问之前，是的，我将每个属性用引号括起来），所以
然后我必须用UPDATE语句重新插入它们如果我希望系统能够互相交流。
有什么想法吗？
On Sun，28 2003年12月23:47:25 +0000（UTC），Erland Sommarskog
< so **** @ algonet.se>写道：
Yes, this is really nice because the user still only has to have
permission to execute the stored procedure. :)
Actually I found a problem with OPENXML that I''ve been meaning to
post. We have legacy flat-file systems (which of course we want to
replace, but we can''t just snap our fingers and bingo it''s done) that
use the equivalent of a char field for various numeric-appearing
identifiers such as our contract numbers. So for example, the
contract number field in the legacy system is 10 characters, but right
now we''re still in the 700000''s so it shows up as four spaces followed
by six numeric characters. OPENXML eats all the leading spaces
(Before you ask, yes, I am enclosing each attribute in quotes), so
then afterwards I have to reinsert them with an UPDATE statement if I
want the systems to talk to each other.
Any thoughts?
On Sun, 28 Dec 2003 23:47:25 +0000 (UTC), Erland Sommarskog
<so****@algonet.se> wrote:
这是一个很好的附带好处，就是使用XML我们突然得到了一个方法，只需一个将大量数据插入SQL Server网络上的往返：发送XML文档，
然后说INSERT ... OPENXML。
A nice side benefit of this, is that with XML we suddenly have
gotten a method of inserting lots of data into SQL Server with
just one roundtrip on the network: send down the XML document,
and then say INSERT ... OPENXML.
这篇关于关系模型和XML的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
