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How to Declare a Namespace in XQuery
Originally posted: 2021-05-08
A simple example of how to declare a namespace in XQuery so you can quickly and easily run XPath and XQuery on namespace elements
Namespace prefix has not been declared error
Namespaces can be a big pain. If you try to run an XQuery on something like an XSL stylesheet (where all the XSL elements are prefixed with the xsl: prefix), you might run into an error like this:
Namespace prefix 'xsl' has not been declared
Solution
The solution is as simple as declaring the namespace. Here’s an example:
declare namespace xsl = "http://www.w3.org/1999/XSL/Transform";
count(//xsl:template)