My point is that my application is more like a spell checker -- which would probably be terribly inefficient if implemented via mysql. I suppose a super long query like,

"Select Code,Instances from Codes where code in ('cdfe','abcd','asdf','qwet',...)"

would be the most efficient query. (I would expect to retrieve 10,000 to 100,000 codes for a typical query.) HOWEVER -- even with indices, this seems more like a "DBM" rather than an RDBM problem.