Determining the Position Number of a Node

The position() function returns an integer that indicates the position of the node within the parent. Positions start with 1; a node with a position of 1 is always the first node in the collection.

For example, the following query returns the first three degree elements in the document:

(//degree)[position() < 4] 
               

            

The next query finds the first two book children in the current context:

book[position() <= 2] 
               

            

The XPath processor executes the position() function with respect to the parent node. Consider the following data:

<x>
               

              
<y/>
                   
<y/>
                   

                
</x> <x>
<y/>
                   
<y/>
                   

                
</x>

The following expression returns the first y element contained in each x element:

x/y[position() = 1] 
               

            

For more information, see also Finding an Element with a Particular ID.

 
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