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Thanks Alex - yes, good point. I forgot about that technique! I'll try it ... -- Guy -----Original Message----- From: Blackboard/Courseinfo userslist [mailto:[log in to unmask]] On Behalf Of Alex Fraser Sent: 01 December 2011 16:50 To: [log in to unmask] Subject: Re: XML Snapshot: Empty XML tags in "manual mode" Hi Guy, Sorry to hear that! I don't consider myself an expert on XML but whether whitespace nodes are considered significant or not is an option when using XSLT, ie "<x> </x>" may or may not be equivalent to "<x></x>" (which, as you wrote, is equivalent to "<x/>"). If the distinction is being lost somewhere in the process, it ought to be fixable... Another simple thing to try would be "<x><![CDATA[ ]]></x>" instead. This may "survive" to be interpreted by Learn as a single space, avoiding the issue you describe below. Kind regards, Alex Alex Fraser e-Learning Technologist (Systems) Learning Technology Team (LTT) | SITS & Learning Technology Lecture Centre LC016, Brunel University, Uxbridge, UB8 3PH, UK t: +44 1895 265232 e: [log in to unmask] Get updates on Brunel's Blackboard Learn implementation at the project blog: http://bbblearn.com/ -----Original Message----- From: Blackboard/Courseinfo userslist [mailto:[log in to unmask]] On Behalf Of Guy Richard Heatley Sent: 01 December 2011 12:20 To: [log in to unmask] Subject: Re: XML Snapshot: Empty XML tags in "manual mode" Having tested Alex's idea of using a single space ... it doesn't work :-( This is actually due to the specification of XML which enforces the protocol that a tag enclosing only whitespace is seen as empty. e.g. <some_tag> </some_tag> (single whitespace) Is the same as <some_tag></some_tag> (empty tag, equivalent to: <some_tag /> ) The Oracle function that extracts the XML (in my sync process) knows this, and applies this rule to the XML thus removing the spaces I added! I have resorted to escaping the space like this, to an HTML entity, and the ampersand to an XML entity: "<middle>&nbsp; </middle>". (Nbsp = Non-breaking space) This is OK providing the name only ever appeared on webpages which would render " " as a single space. Anywhere else it would appear as "Bob Dobbs", but on a webpage correctly: "Bob Dobbs". -- Guy -----Original Message----- From: Blackboard/Courseinfo userslist [mailto:[log in to unmask]] On Behalf Of Alex Fraser Sent: 25 November 2011 15:52 To: [log in to unmask] Subject: Re: XML Snapshot: Empty XML tags in "manual mode" Hi Guy, As we are working towards Snapshot integration, I recently read the "Advanced Integration and Data Management Guide" and noted the problem you describe as a potential issue. Referring to the flat file format there is the following paragraph (p46): "Information that is not given (left blank) for fields that are included in the header is not changed during the operation. ... To clear a field, enter a single space." The behaviour you are seeing with an XML feed file is consistent with this, so I would hope whitespace is preserved and a single space will have the effect for an XML feed file as it is documented to for a flat feed file. I can't test it yet, but it seems like a good thing to try! Hope this helps, Alex Alex Fraser e-Learning Technologist (Systems) Learning Technology Team (LTT) | SITS & Learning Technology Lecture Centre LC016, Brunel University, Uxbridge, UB8 3PH, UK t: +44 1895 265232 e: [log in to unmask] Get updates on Brunel's Blackboard Learn implementation at the project blog: http://bbblearn.com/ -----Original Message----- From: Blackboard/Courseinfo userslist [mailto:[log in to unmask]] On Behalf Of Guy Richard Heatley Sent: 25 November 2011 14:45 To: [log in to unmask] Subject: XML Snapshot: Empty XML tags in "manual mode" Hello! Here at UCLan we use a daily XML file extracted from our student record system to synchronise Blackboard with current users and institution roles. I run the XML that syncs the users in "manual mode" which means records are never deleted, just inserted or updated. (To delete users I use a separate XML file that has been explicitly created, to avoid accidents!) Anyway, I have noticed a strange "feature" of the XML sync process that becomes apparent if a user permanently drops their middle name:- If the student record system recorded that Bob Sigmund Dobbs had dropped his middle name the following XML would result: The XML file produces an empty XML tag for that field e.g. <first>Bob</first> <middle /> <last>Dobbs</last> Blackboard does not see the empty tag as an instruction to update this field to empty and performs no action. i.e. Bob still appears to have a middle name of Sigmund. Does anyone know how to update a field to empty/null via the xml manual process? I suppose this leads to the old database chestnut confusing a field that is definitely known to be empty, with a field for which we have no known data (i.e. null). Cheers! -- Guy