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The basic construction block of XQuery is an expression. XQuery is a function language that allows multiple expressions to nested. He is also a strong type of language. Just like XML, XQuery is a case-sensitive language. All keywords in xQuery uses lowercase characters.
The value of the expression is always serialized, and is an ordered collection of 0 or more items. A project can be an atom (microparticle) value or a node (Node).
In the document, the XML Outline Type Name Space Prefix XS: and XSI: and XPath / XQuery Method Name Space Prefix FN: Some time, the discussion is clear and the namespace is not important, the built-in XML outline type name is like integer and string You don't have to bring a namespace prefix.
