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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For further information on XPath click here.
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.
For further information on XQuery click here.
Besides these
XQuery grounds on the five expressions whose acronym is FLWOR (pronounced "flower").
- For - selects a sequence of nodes
- Let - binds a sequence to a variable
- Where - filters the nodes
- Order by - sorts the nodes
- Return - what to return (gets evaluated once for every node)
With these expressions (not necessarily with all of them) one can query any XML data.
Besides the main features of XQuery there is an extension called XQuery Update Facility which introduces some useful features to XQuery.
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