RE: XQuery parameters

Dear Stephane

 

Note that I am not saying yet whether such a mechanism will be part, just that we consider it.

 

Note that the workaround would mean that every user would have to write his own function. There is no preferred function name and signature (like C's main()). One of the mechanism under consideration would be to require such a standard function name, while others are to simply allow the binding of variables into the evaluation context using a declaration in the query prolog.

 

With the Nov 15th working draft, you are already allowed to add externally variables to the XQuery static and dynamic contexts as predefined variables. That is helpful if you embed your query in a static way into your programming language.

 

Best regards

Michael

 

-----Original Message-----
From: Stéphane Mbaye [mailto:stephane.mbaye@gael.fr] 
Sent: Monday, November 18, 2002 9:57 AM
To: XQuery
Subject: RE: XQuery parameters

 

Dear Michael,

 

thank your for your answer. I am happy that a parameter mechanism will be part of XQuery language.

I believe the workaround you've proposed is a good temporary solution until the XQuery language will

specify the mechanism. I will have no problem to wrap an expression into a parameterized function

because it is our implementation of XQuery engine (i.e. http://www.gael.fr/drb ).

 

However in order to minimize the changes on XQuery scripts using the workaround solution when the

mechanism will be explicitly specified in the XQuery language, may you provide me with trends about

the function name and prototype ?

 

Thank you in advance for your help.

Best regards.

 


 

Stéphane

Mbaye


  _____  

 

 


GAEL Consultant 

Cité Descartes
18, rue Albert Einstein
77420 Champs-sur-Marne
France 

Software Director

 


mailto:stephane.mbaye@gael.fr
http://www.gael.fr 

 

 


tel +33-(0)1 64 73 99 55
fax +33-(0)1 64 73 51 60

 

 

 

 

 

-----Message d'origine-----
De : www-ql-request@w3.org [mailto:www-ql-request@w3.org]De la part de Michael Rys
Envoyé : jeudi 14 novembre 2002 19:41
À : Stéphane Mbaye; XQuery
Objet : RE: XQuery parameters

 

Dear Stephane

 

Thanks for your comment and suggestion. We are currently indeed looking into such mechanisms.

 

Although as a workaround, you could always wrap your XQuery expression into a parameterized function and provide the function parameter as part of your function invocation (this assumes that the XQuery API provides a way to call an XQuery function directly).

 

Best regards

Michael

 

-----Original Message-----
From: Stéphane Mbaye [mailto:stephane.mbaye@gael.fr] 
Sent: Thursday, November 14, 2002 6:55 AM
To: XQuery
Subject: XQuery parameters

 

Dear Sirs,

 

does the XQuery language foresee a mechanism for parameters set outside the query script ?

Such a system would enable the evaluation of queries from different documents or with different

extents, constants, etc. without modifying the source code of the query.

 

The parameter may be atomic values, possibly labeled or identified by a QName and have a default value

such as attributes of XML elements.

 

As an example a parameterized query may be :

 

<authlist>

 {

   let $input := document( parameter("inputDocument",xsd:anyURI,"bibl.xml") <!-THE PARAMETER -->

   for $a in distinct-values($input//author)

   return

     <author>

      {

        <name>

           { $a/text() }

        </name>,

        <books>

         {

           for $b in $input//book

           where $b/author = $a

           return $b/title 

         }

        </books>

      }

     </author>

 }

</authlist>

 

Best regards

 


 

Stéphane

Mbaye


  _____  

 

 


GAEL Consultant 

Cité Descartes
18, rue Albert Einstein
77420 Champs-sur-Marne
France 

Software Director

 


mailto:stephane.mbaye@gael.fr
http://www.gael.fr 

 

 


tel +33-(0)1 64 73 99 55
fax +33-(0)1 64 73 51 60