Use of For loop in transforming a node without changing the database
Thursday, 24 February 2011 · 1 message
SV
Sony Vijay24 Feb 2011 22:25 #
Christian,
Thank you very much for helping me with the query. However, I am not quite sure how the transform operation works if I have to use a for loop. Say, I twist around yesterday's question a bit like so:
copy $c :=
<entry>
<id>1</id>
<title>How to use a transform expression</title>
<updated>2011-02-23</updated>
<author>
<name>BaseX Team</name>
<uri>http://basex.org</uri>
</author>
<childentry> 1 </childentry>
<childentry> 2 </childentry>
<childentry> 3 </childentry>
<content type="html">Transform expression example created by BaseX Team</
content>
</entry>
modify (
replace value of node $c//name with 'BaseX',
replace value of node $c//content with concat('Copy of: ', $c//content),
insert node <member>Joey</member> into $c//author
for $childentry in $c//childentry
replace value of $childentry with concat('New Child: ',
$c//childentry/text())
)
return $c *The expected output is:*
<entry>
<id>1</id>
<title>How to use a transform expression</title>
<updated>2011-02-23</updated>
<author>
<name>BaseX</name>
<uri>http://basex.org</uri>
<member>Joey</member>
</author>
<childentry> *New Child: 1* </childentry>
<childentry> *New Child: 2 *</childentry>
<childentry> *New Child: 3* </childentry>
<content type="html">Copy of: Transform expression example created by BaseX
Team</content>
</entry>The following exception is thrown when I tried my sample transformation query with the for loop:
*[XPST0003] Expecting 'where', 'order' or 'return' expression.*
Thanks,
Sony
*PS: @Lukas: I did notice the update in the documentation. Thank you !*
Quoted text · Lukas Kircher · 126 lines
On Wed, Feb 23, 2011 at 2:32 AM, Lukas Kircher <lukaskircher1 at googlemail.com > wrote: > Hi Sony, > > to help others with the same question, I allowed myself to > add a modified version of your example to our > documentation [1]. > > Regards, > Lukas > > > [1] http://docs.basex.org/wiki/Update#transform > > > > > On Wed, Feb 23, 2011 at 6:58 AM, Sony Vijay <sony.vibh at gmail.com> wrote: > >> Christian, >> >> Thank you for the quick and helpful reply. >> >> - Sony >> >> >> On Tue, Feb 22, 2011 at 5:56 PM, Christian Grün < >> christian.gruen at gmail.com> wrote: >> >>> Sony, >>> >>> the following query might do what you want: >>> >>> copy $c := >>> <entry xmlns="http://www.w3.org/2005/Atom" >>> xmlns:libx="http://libx.org/xml/libx2"> >>> <id>1</id> >>> <title>Link Amazon By ISBN</title> >>> <updated>2010-09-29T18:37:48.592Z</updated> >>> <author> >>> <name>LibX Team</name> >>> <uri>http://libx.org</uri> >>> <email>libx.org at gmail.com</email> >>> </author> >>> <content type="html">Content created by LibX Libapp Builder</content> >>> </entry> >>> modify ( >>> replace value of node $c//*:name with 'Sony', >>> replace value of node $c//*:content with >>> concat('Copy of: ', $c//*:content) >>> ) >>> return $c >>> >>> >>> Best, >>> Christian >>> ___________________________ >>> >>> On Tue, Feb 22, 2011 at 11:43 PM, Sony Vijay <sony.vibh at gmail.com> >>> wrote: >>> > Hi, >>> > I am using BaseX 6.5. I am trying to transform a given node using an >>> > XQuery. >>> > >>> > Say, I have an node like so: >>> > <entry xmlns="http://www.w3.org/2005/Atom" >>> > xmlns:libx="http://libx.org/xml/libx2"> >>> > <id>1</id> >>> > <title>Link Amazon By ISBN</title> >>> > <updated>2010-09-29T18:37:48.592Z</updated> >>> > <author> >>> > <name>LibX Team</name> >>> > <uri>http://libx.org</uri> >>> > <email>libx.org at gmail.com</email> >>> > </author> >>> > <content type="html">Content created by LibX Libapp Builder</content> >>> > </entry> >>> > I am trying to send this node to an xquery which is expected to do the >>> > following actions: >>> > >>> > create a copy of this node (so that the actual node in the database >>> does not >>> > change), >>> > transform/modify the duplicate copy of the given node >>> > return the modified duplicate copy of the given node >>> > >>> > I would expect the output to be like so: >>> > <entry xmlns="http://www.w3.org/2005/Atom" >>> > xmlns:libx="http://libx.org/xml/libx2"> >>> > <id>1</id> >>> > <title>Link Amazon By ISBN</title> >>> > <updated>2010-09-29T18:37:48.592Z</updated> >>> > <author> >>> > <name>Sony</name> >>> > <uri>http://libx.org</uri> >>> > <email>libx.org at gmail.com</email> >>> > </author> >>> > <content type="html">Copy of: Content created by LibX Libapp >>> > Builder</content> >>> > </entry> >>> > I tried to perform the non-updating functions using transform and also >>> tried >>> > to use a pending update list >>> > (Reference: http://docs.basex.org/wiki/Update#transform). None of this >>> works >>> > as expected. Could you refer me to a more detailed documentation for >>> > performing such transform operations on nodes ? >>> > Thanks, >>> > Sony >>> > >>> > _______________________________________________ >>> > BaseX-Talk mailing list >>> > BaseX-Talk at mailman.uni-konstanz.de >>> > https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk >>> > >>> > >>> >> >> >> _______________________________________________ >> BaseX-Talk mailing list >> BaseX-Talk at mailman.uni-konstanz.de >> https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk >> >> >
Written for BaseX 6. BaseX may have changed since: please check the current documentation.
⚡Generated with XQuery