How can I use XML?

hi,

I've read the article on XML basics and other articles here and there but i'm still wondering how can i use xml and what is it really for?

is it another layer in the application?

I mean, to share data with others on different platforms, can't that be done using just a database? and if i I need to display it on varying devices can't a database and a language(jsp, php, asp, etc..) do the trick?

Why do i need xml?

can someone point me to a reference point or help me out here?

thanks
edwin

You should probably see xml as an api which means that by defining a dtd or a xsd you make it possible for other systems to understand the structure of your xml and to plugin

An easy to understand implementation is html.
All element- and attributenames are described in a dtd which is implemented in all html enabled applications such as webbrowsers.

The result is a uniform data visualisation and sharing of html.

xml is a possible solution dedicated datasharing, -processing and -visualisation. (Large) companies can define their xml structure they want to use for projects or whatever and by making the definition public other companies such as suppliers can develop applications that can read and process those xml files.

for some real life implementations of xml you might want to look at
URL
This is an explanation of the xml structure for the building industry

URL
who have defined xml based structures for electronic learning environments

For viewing editing and validatind xml (related) files I reccomend you download a copy of turbo xml at URL
(examples included)

pwijdh,

ok. so after describing all my data into nicely organized pieces. how do i share it with other ppl? store it in a database?

but why can't i just use a database and why describe it all in xml? isn't a database more powerful in terms of storing and organizing data?

thanks
edwin

Most examples and tutorials about XML show it as text files that are then converted to HTML or WAP or something. You're right, this wouldn't make much sense to store a large amount of data this way. A database makes more sense. What XML is great for is transfering that data between different companies/depts/etc.

For example, let's say you were going to share your widget product database with your biggest customer WidgWorld. They're going to get the latest data from your database and show it on their ecommerce site. You don't want to just give WidgWorld a password and let them do whatever they want with your data. So instead you create a script/servlet/app that sends the data in XML form. Before you probably would have sent comma or tab separated text but that doesn't show irregular data (some widgets have 3 unique features others have 1) and isn't self describing. Also if 2 differenct customers are getting this XML feed you can add a new tag (<color>Blue</color>) and the parser will ignore until they decide to parse for it, a sudden new column in the text table would probably screw everything up.

thanks man,

I really need to start learning sooo much stuff and xml/xslt will be some of them....

are u working with xml now?

edwin

Good site here:
http://www.phpxml.org

py