How about sucess rate? if you are high level and use it on a lower monster it will work mostly, on monsters with about the same level as you will have 30%-40% of working, and higher monsters is lower, of course with bosses it won't work ;) Also it seems a good idea to need some reather hard or expen...

You could look the the ODK project, which offers a database agnostic access, and has C++ bindings, works on Linux, *BSD and Windows, and currently supports SQLite, MySQL and PostgreSQL, SQLite3 plugin is on development and will support other databases as well, transparently. Ok, that was a shameless...