XPath
XPath is the XML Path Language which uses a "path like" syntax to browse through elements and attributes in an XML document.
It contains over 200 built-in functions for such as string values, numeric values, booleans, date and time comparison, node manipulation, sequence manipulation, and much more.
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XQuery
XQuery is a language that designed to query XML data. It is built on XPath expressions so one that wants to use XQuery must know how to use XPath.
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