Re: XQuery Update to return values

Hi Emma,

In the current spec, you can either change a data model instance with a 
query that generates a pending update list, or do a transform or a 
query, but you can't do both. And all expressions in an update are 
evaluated within one snapshot.

The Scripting Extensions for XQuery will introduce statements, allowing 
expressions to be evaluated after an update has been made. Only the 
requirements document currently exists:

http://www.w3.org/TR/xquery-sx-10-requirements/

In the meantime, you can do this if you embed XQuery in a procedural 
language.

Hope this helps!

Jonathan

Wu, Emma wrote:
> The query below does not change the original document. Only the copied var $newVar is updated.
> I need the $var to be updated and return the updated $var as well. Any idea? Thanks.
>
> Emma
>
>
> -----Original Message-----
> From: Carmelo Montanez [mailto:carmelo@nist.gov]
> Sent: Fri 7/27/2007 9:41 AM
> To: Wu, Emma; www-ql@w3.org
> Subject: Re: XQuery Update to return values
>  
> Emma:
>
> If I am not mistaken, you can use a Transform expression, which will 
> return a value back.
> Something like this:
>
> let $var := fn:doc("works-mod.xml")/works[1]/employee[1]
> let $var1 := <pnum>P1-1</pnum>
> return
>   transform
>    copy $newVar := $var
>    modify do replace $newVar/pnum[1] with $var1
>    return $newVar
>
> Thanks,
> Carmelo
>
>
> At 02:02 PM 7/26/2007, Wu, Emma wrote:
>   
>> Hi,
>>
>> The problem I am trying to solve is that with XQuery Update 
>> faicility, I will update an element and at the same time, I want the 
>> same element to be returned. Something like the following:
>>
>> 1. update a book element's author
>> 2. return the updated book element
>>
>> Is there a way to do it in one query instead of two separate 
>> queries? And it looks like update expression does not return anything
>>
>> Thanks,
>> Emma
>>
>>
>>
>>
>>     
>
>
>
>

Received on Friday, 27 July 2007 18:30:06 UTC