XQuery Functions against the xml Data Type

SQL Server 2008 Books Online (October 2009)

This topic and its subtopics describe the functions you can use when specifying XQuery against the xml data type. For the W3C specifications, see http://www.w3.org/TR/2004/WD-xpath-functions-20040723.

The XQuery functions belong to the http://www.w3.org/2004/07/xpath-functions namespace. The W3C specifications use the "fn:" namespace prefix to describe these functions. You do not have to specify the "fn:" namespace prefix explicitly when you are using the functions. Because of this and to improve readability, the namespace prefixes are generally not used in this documentation.

The following table lists the XQuery functions that are supported against the xml data type.

Category	Function Name
Functions on Numeric Values	ceiling
	floor
	round
XQuery Functions on String Values	concat
	contains
	substring
	lower-case Function (XQuery)
	string-length
	upper-case Function (XQuery)
Functions on Boolean Values	not
Functions on Nodes	number
	local-name Function (XQuery)
	namespace-uri Function (XQuery)
Context Functions	last
	position
Functions on Sequences	empty
	distinct-values
	id Function (XQuery)
Aggregate Functions (XQuery)	count
	avg
	min
	max
	sum
Constructor Functions (XQuery)	Constructor Functions
Data Accessor Functions	string
	data
Boolean Constructor Functions (XQuery)	true Function (XQuery)
	false Function (XQuery)
Functions Related to QNames (XQuery)	expanded-QName (XQuery)
	local-name-from-QName (XQuery)
	namespace-uri-from-QName (XQuery)
SQL Server XQuery Extension Functions	sql:column() function (XQuery)
	sql:variable() function (XQuery)

Other Resources

xml Data Type Methods
XQuery Language Reference (Database Engine)
Implementing XML in SQL Server

Help and Information

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