Beginning Microsoft SQL Server 2008 ... - S3 Tech Training

As a side note, you can perform a rather quick and dirty check to see whether your XML is well formed
or not by opening the document in Microsoft’s Internet Explorer — it will complain to you if the document
is not well formed.
For this example, we’re going to look at an XML representation of what some of our AdventureWorks2008
data might look like. In this case, I’m going to take a look at some order information. We’re going to start
with just a few things and grow from there.
First, we know that we need a root node for any XML document that we’re going to have. The root node
can be called anything we want, as long as it is unique within our document. A common way of dealing
with this is to call the root root. Another common example would be to call it something representative
of what the particular XML document is all about.
For our purposes, we’ll start off with something hyper-simple, and just use root:
Just that quickly we’ve created our first well-formed XML document. Notice that it didn’t include the
tag that we saw in the earlier illustration. We could have put that in, but it’s actually an optional
item. The only restriction related to it is that, if you include it, it must be first. For best practice reasons as
well as clearness, we’ll go ahead and add it:
Actually, by the rules of XML, any tag starting with is considered to be a reserved tag — that is,
you shouldn’t name your tags that, as they are reserved for current or future use of the W3C as XML
goes into future versions.
So, moving on, we have our first well-formed XML document. Unfortunately, this document is about as
plain as it can get — it doesn’t really tell us anything. Well, for our example, we’re working on describing
order information, so we might want to start putting in some information that is descriptive of an
order. Let’s start with a SalesOrderHeader tag:
OK — so this is getting monotonous — isn’t it? We now know that we have one order in our XML document,
but we still don’t know anything about it. Let’s expand on it some by adding a few attributes:
Chapter 16: A Brief XML Primer
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