If you have an attribute assignment on page "pageA" e.g. like [[Attribute1::{{#show:pageB|?Attribute2 |link=none}} ]] and you change the Attribute2 value on pageB the Attribute1 on pageA won't be update.
If you use action=purge it will update the rendered output but the saved properties still won't be updated! You can see it on the Special:Browse page there will still be the old value.
Only when you edit and save the pageA the properties value will be updated.
Now imagine you have a pageC which will get a value depending on pageA which depends on pageB which perhaps depends on another pages value...
I use this e.g. for family names and other more complex stuff.
Example in the sandbox (pageA):
http://sandbox.semantic-mediawiki.org/index.php?title=Dynamic_attribute_purge_test
Change the attribute at (pageB):
http://sandbox.semantic-mediawiki.org/wiki/Dynamic_attribute_source
and then purge on pageA:
http://sandbox.semantic-mediawiki.org/index.php?title=Dynamic_attribute_purge_test&action=purge
So at least purging a page should update attributes. Even better would be an "internal link" or something like it is with templates. Whenever a page changes which you use in a inline query the page with the query should purge automatically when calling it the first time after the change on the other page.
Version: unspecified
Severity: major
URL: http://sandbox.semantic-mediawiki.org/index.php?title=Dynamic_attribute_purge_test