ographic area.  All the databases cover the same basic
&gt; &gt; information, but all the table names, field names, and symbols may be
&gt; &gt; different from one database to the next.
&gt; &gt;    We created an ontology of real estate in first order
&gt; &gt; logic, using an
&gt; &gt; upper ontology.
&gt;
&gt;MW: An ontology is really overkill for this.

I think this is simply a question of personal preference and 
experience.  My understanding is that you're not familiar with logic so 
it's not surprisin