[seek-dev] XQuery and XQueryX

[Dan Higgins]

Please note that the comment about "verbosity won't matter much..." in 
my orignal message was part of the quote from the originally referenced 
web page! I was just sharing information, not recommending anything in 
particular.

Dan Higgins

---

Peter McCartney wrote:

> well i know Matt loves the power of xml to turn 7 lines into 21 
> without saying anything different.
>
> Is this really need to assist machine parsing? look at this website 
> http://www.w3.org/2002/08/applets/xqueryApplet.htm
> which show the resulting tree from the xquery parser available on the 
> same site. Is xqueryx any easier to process than the output from the 
> parser?
>
> Another way to look at it is which syntax is easier to build up from a 
> user form interface? Realistically, our search pages are likely to 
> build simple for expressions and probably no let expressions. The 
> greates complexity will be in building the where clause for which your 
> website doesn't show an example of. Im willing to bet, though, that 
> its not unlike the concept boolean+concept+operator+value syntax we 
> had in Seattle
>
>  
> for $dataset in /eml/dataset
> where $dataset/creator/individualName/surname = 'Smith'
> return
> <EML>
> {
> $dataset
> }
> </EML>
>
> Peter McCartney (peter.mccartney at asu.edu)
> Center for Environmental-Studies
> Arizona State University
>
> -----Original Message-----
> From: Dan Higgins [mailto:higgins at nceas.ucsb.edu]
> Sent: Thursday, May 15, 2003 6:40 PM
> To: seek-dev at ecoinformatics.org
> Subject: [seek-dev] XQuery and XQueryX
>
>
> Hi All,
>
> An interesting introduction to XQuery is on IBMs DeveloperWorks site at
>
> http://www-106.ibm.com/developerworks/xml/library/x-xquery.html
>
> One item that I remembered being discussed in San Diego is whether an 
> XQuery is just an expression. Apparently an alternate XML syntax  
> called 'XQueryX' exists for machine parsing. See the example below 
> from the refernced article
>
> Listing 1. A simple query in standard syntax
>
>
>    let $authors := /book/author
>    return
>       <AUTHORS>
>       {
>          $authors
>       }
>       </AUTHORS>
>
>
>
> and Listing 2 shows the equivalent in XQueryX:
> Listing 2. The same query in XQueryX format
>
>
>    <q:query xmlns:q="http://www.w3.org/2001/06/xqueryx">
>       <q:flwr>
>          <q:letAssignment variable="$authors">
>             <q:step axis="CHILD">
>                <q:identifier/>
>                <q:step axis="CHILD">
>                   <q:identifier>book</q:identifier>
>                   <q:identifier>author</q:identifier>
>                </q:step>       
>             </q:step>         
>          </q:letAssignment>
>          <q:return>
>             <q:elementConstructor>
>                <q:tagName>
>                   <q:identifier>AUTHORS</q:identifier>
>                </q:tagName>
>                <q:variable>$authors</q:variable>
>             </q:elementConstructor>
>          </q:return>
>       </q:flwr>
>    </q:query>
>
>
>
> Verbosity won't matter much to the machine that's processing this 
> (unless we're talking really big queries), but it would be a bit of a 
> struggle for a human operator doing some actual debugging.
>
> -- 
> *******************************************************************
> Dan Higgins                                  higgins at nceas.ucsb.edu
> http://www.nceas.ucsb.edu/    Ph: 805-892-2531
> National Center for Ecological Analysis and Synthesis (NCEAS)
> 735 State Street - Room 205
> Santa Barbara, CA 93195
> *******************************************************************
>


-- 
*******************************************************************
Dan Higgins                                  higgins at nceas.ucsb.edu
http://www.nceas.ucsb.edu/    Ph: 805-892-2531
National Center for Ecological Analysis and Synthesis (NCEAS) 
735 State Street - Room 205
Santa Barbara, CA 93195
*******************************************************************

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mercury.nceas.ucsb.edu/ecoinformatics/pipermail/seek-dev/attachments/20030516/c7cf6581/attachment.htm