i'm not new to mySQL, but i'm not familiar with advanced features, so my q is:
is it possible to link a column in a table on one DB to a column in a different table on ANOTHER DB, such that wen one value is updated, so is the other?
if so, how?
i think what you want is a trigger, and they are supported as of MySQL 5.
or maybe an update cascade. hmm.
sounds like bad design imho. you should probably not be doing this in true relational database coding.