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last Function (XQuery)

Returns the number of items in the sequence that is currently being processed. Specifically, it returns the integer index of the last item in the sequence. The first item in the sequence has an index value of 1.

Syntax

fn:last() as xs:integer

Remarks

In SQL Server, fn:last() can only be used in the context of a context-dependent predicate. Specifically, it can only be used inside brackets ([ ]).

Examples

This topic provides XQuery examples against XML instances that are stored in various xml type columns in the AdventureWorks database. For an overview of each of these columns, see xml Data Type Representation in the AdventureWorks Database.

A. Using the last() XQuery function to retrieve the last two manufacturing steps

The following query retrieves the last two manufacturing steps for a specific product model. The value, the number of manufacturing steps, returned by the last() function is used in this query to retrieve the last two manufacturing steps.

SELECT ProductModelID, Instructions.query(' 
declare namespace AWMI="https://schemas.microsoft.com/sqlserver/2004/07/adventure-works/ProductModelManuInstructions";
  <LastTwoManuSteps>
   <Last-1Step> 
     { (/AWMI:root/AWMI:Location)[1]/AWMI:step[(last()-1)]/text() }
   </Last-1Step>
   <LastStep> 
     { (/AWMI:root/AWMI:Location)[1]/AWMI:step[last()]/text() }
   </LastStep>
  </LastTwoManuSteps>
') as Result
FROM Production.ProductModel
WHERE ProductModelID=7

In the preceding query, the last() function in //AWMI:root//AWMI:Location)[1]/AWMI:step[last()] returns the number of manufacturing steps. This value is used to retrieve the last manufacturing step at the work center location.

This is the result:

ProductModelID Result  
-------------- -------------------------------------
7      <LastTwoManuSteps>
         <Last-1Step>
            When finished, inspect the forms for defects per 
            Inspection Specification .
         </Last-1Step>
         <LastStep>Remove the frames from the tool and place them 
            in the Completed or Rejected bin as appropriate.
         </LastStep>
       </LastTwoManuSteps>