The DB_ stuff are just global tables/lists which you don't have to make a formal declaration. As far as I know they take on the type of the first time one is set.
Therefore DB_fruit("apple") creates a table called DB_fruit of the String type with one entry.
Osiris can catch when one of these entries is set. (as an event.) And you should be able to set an entry or a tag or an event or something like that from a script to trigger an osiris event.
