XQuery Adding Elements and Attributes
The XML Example Document
We will use the "books.xml" document in the examples below (same XML file as in the previous chapters).
View the "books.xml" file in your browser.
Adding Elements and Attributes to the Result
As we have seen in a previous chapter, we may include elements and attributes from the input document ("books.xml) in the result:
for $x in doc("books.xml")/bookstore/book/title
order by $x
return $x
The XQuery expression above will include both the title element and the lang attribute in the result, like this:
<title lang="en">Everyday Italian</title>
<title lang="en">Harry Potter</title>
<title lang="en">Learning XML</title>
<title lang="en">XQuery Kick Start</title>
The XQuery expression above returns the title elements the exact same way as they are described in the input document.
We now want to add our own elements and attributes to the result!
Add HTML Elements and Text
Now, we want to add some HTML elements to the result. We will put the result in an HTML list - together with some text:
<html>
<body>
<h1>Bookstore</h1>
<ul>
{
for $x in doc("books.xml")/bookstore/book
order by $x/title
return <li>{data($x/title)}. Category: {data($x/@category)}</li>
}
</ul>
</body>
</html>
The XQuery expression above will generate the following result:
<html>
<body>
<h1>Bookstore</h1>
<ul>
<li>Everyday Italian. Category: COOKING</li>
<li>Harry Potter. Category: CHILDREN</li>
<li>Learning XML. Category: WEB</li>
<li>XQuery Kick Start. Category: WEB</li>
</ul>
</body>
</html>
Add Attributes to HTML Elements
Next, we want to use the category attribute as a class attribute in the HTML list:
<html>
<body>
<h1>Bookstore</h1>
<ul>
{
for $x in doc("books.xml")/bookstore/book
order by $x/title
return <li class="{data($x/@category)}">{data($x/title)}</li>
}
</ul>
</body>
</html>
The XQuery expression above will generate the following result:
<html>
<body>
<h1>Bookstore</h1>
<ul>
<li class="COOKING">Everyday Italian</li>
<li class="CHILDREN">Harry Potter</li>
<li class="WEB">Learning XML</li>
<li class="WEB">XQuery Kick Start</li>
</ul>
</body>
</html>
