XQuery Sequence Functions

Let's see the list of commonly used sequence functions provided by XQuery:

Index	Name	Description
1)	count($seq as item()*)	It is used to count the items in a sequence.
2)	sum($seq as item()*)	It is used to return the sum of the items in a sequence.
3)	avg($seq as item()*)	It is used to return the average of the items in a sequence.
4)	min($seq as item()*)	It is used to return the minimum valued item in a sequence.
5)	max($seq as item()*)	It is used to return the maximum valued item in a sequence.
6)	distinct-values($seq as item()*)	It returns select distinct items from a sequence.
7)	subsequence($seq as item()*, $startingloc as xs:double, $length as xs:double)	It is used to return a subset of provided sequence.
8)	insert-before($seq as item(), $position as xs:integer, $inserts as item())	It is used to insert an item in a sequence.
9)	remove($seq as item()*, $position as xs:integer)	It is used to remove an item from a sequence.
10)	reverse($seq as item()*)	It is used to return the reversed sequence.
11)	index-of($seq as anyatomictype()*, $target as anyatomictype())	It returns indexes as integers to indicate availability of an item within a sequence.
12)	last()	It returns the last element of a sequence when used in predicate expression.
13)	position()	It is used in FLOWR expressions to get the position of an item in a sequence.