&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt;MW: Please explain how you think that might work.
&gt; &gt; &gt;
&gt; &gt; &gt; Imagine that a database technician reverses the fields 
&gt; that should be
&gt; &gt; &gt; mapped from a client database into a common DB.  He flips
&gt; &gt; &gt; birth date and
&gt; &gt; &gt; hire date (for an employee database for a multinational
&gt; &gt; &gt; corporation for
&gt; &gt; &gt; example).  As each record is pulled into the common DB it's
&gt; &gt; &gt; checked against
&gt; &