[protege-discussion] Protege 3.3.1 DB Schema

[Jonathan Carter]

Hi Dennis,

From my experience of the database schema, I would advise against operating directly (even reading) the underlying database table (note: singular).

Protege database is basically a meta-meta-database. So, all your classes and instances and everything are just instances of the meta-meta classes, e.g. Frame. 
(This is roughly speaking - I haven't spent much time on the details of this). It works really nicely but is rather complex to interpret (to say the least) with a lot of references to other rows to follow to get the picture that you have in Protege (the GUI editor).

When Protege sets up the database it puts some indexes in to help with all the look ups required. (Unfortunately, there's an issue with MS SQLServer 2005 which means that Protege 3.3.1 can't create all the indexes)

What I would recommend - and what I use for analysing the ontology with an external application - is an XML rendering of the ontology, using the format that the experimental XML format from the File->SaveAs menu.
I've written a tab widget to snap-shot the knowledge base in this XML format and send it to my analysis application.

The great thing about the XML format is that although all the entries in it are pretty much Classes and Instances (in fact, I just capture the Instances) it's very much easier to interpret - and this could be used to feed a database that is more directly representative of your application / ontology if XML processing is not an option for your user's application.

Regards

Jonathan


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-----Original Message-----
From: "O'neill, Dennis" <doneill at marathonoil.com>

Date: Wed, 18 Feb 2009 17:02:41 
To: User support for Core Protege and the Protege-Frames editor<protege-discussion at mailman.stanford.edu>
Subject: [protege-discussion] Protege 3.3.1 DB Schema


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