Actually, I didn't mean to say that SMW doesn't have namespace separation at all - what I meant is that it's not very useful.

2008/5/20 Sergey Chernyshev <>:
I agree with Denny, don't use Namespaces for any separation of data that you'll need for queries - SMW doesn't have any internal separation (Semantic Forms has some field limitations by namespace, though).

In my experience, the only reason to use Namespaces is to clearly identify the sections of the site for the user which might actually be OK with multiple company setup, although it's not very clear how their data is meshed up when combined in queries - it might not make sense (might need more info about data that this wiki is going to contain).

And definitely don't use categories other then for defining types of Pages and use properties instead.


Sergey Chernyshev

On Tue, May 20, 2008 at 10:26 AM, Denny Vrandečić <> wrote:
Just to get on prerequesite question clear: do you care about restricted

As MediaWiki developers will be quick to point out, MediaWiki really is
bad at per site-visibility etc. Semantic MediaWiki makes this all even
worse, since all the data is queryable from everywhere and not
restricted at all.

So if you meant to setup the wiki so that org A can only see part of the
wiki, org B another part, and there are some pages that have to be seen
by both orgs -- do *not* use a single installation without having
someone who really understands the issue, or you will end up almost
certainly with access violations.

But if you don't care about fine grained access control, then we can
discuss this here :) My feeling says "Use properties" since this feels
like the most natural way to express this, and it allows for some more
powerful features (imagine a wiki used by 12 orgs, and then the orgs
described themselves, and so you could ask for all people that work at
an org in Austria, e.g., which would be rather cumbersome -- though
possible -- with the Categories solution, and plain impossible with the


Krabina Bernhard wrote:
> Dear all,
> I'd like to discuss with you the use of categories, namespaces and
> properties. Consider the following example: Two (or more) Organisations
> agree to set up three wikis:
> - A wiki for organisation A
> - A wiki for organisation B
> - A common wiki for both organisations
> Of course this could be realised by three separate installations of SMW and
> interwiki links. The topic here would be import and export of ontologies for
> the common wiki to reuse data and structures.
> But I'd like to discuss the possibility of having three wikis (or wiki
> sections/portals) in one installation.
> - Should this be done by simple categories [[Category:OrganisationA]]?
> - Should Namespaces be used [[OrgA:Mainpage]]?
> - Should properties be used [[Belongs to::OrganisatonA]]
> What is your opinion.?
> Is it generally wise to use Namespaces in connection with SMW? (I've never
> used them before...).
> Regards,
> Bernhard

Sergey Chernyshev