[rules-users] Database problem

Hi, there. I need advice on how to approach the following. Hope I'm being clear: - I have a database of over 30 tables. - The database is being updated every now and then. - I need to perform a bunch of calculations based on what's on the DB. - Some of the calculations depend on intermediate calculations. - I decided to use Drools in order to perform such calculations. - Rules would take into account a wide range of factors. - I know Drools is aware of facts that exist in its working memory only. - On one hand I'd move the whole DB to the working memory in order to perform the calculations, but then I'd have to keep working memory and DB in sync. - On the other hand I'd invoke Drools to perform specific calculations by passing it only relevant facts, but I think those relevant facts are a lot. Should I try to keep DB and WM in sync? How? Should I try invoking Drools everytime I need a calculation? Are there any other alternatives? Kind regards.