I think VanVorst, Nathanael (Mission Systems) wrote: > > First question: does that approach seem make sense or have I given enough details?
Makes sense, yes. The Rete algorithm that Jess uses is based on an assumption of a potentially large but slowly-changing working memory; anything you can do to partition the data and take it in finite, stable chunks is a good idea. > I bought "JESS In Action" today and have made through about 100 > pages. You haven't gotten to the "good part" (where the meaty examples are) yet. > So far, I haven't encountered examples of grafting JESS to a > database. I noticed on the JESS website > (http://herzberg.ca.sandia.gov/jess/user.shtml) that someone had > written something to do this grafting (Fact Storage Provider > Framework) . I cannot seem to find a simple example of this. The FSPF is neat. It sets things up so that facts that might match your rules will be automatically fetched from a database. It uses Jess's backwards chaining to do this. It may, or may not, suit your purpose. > Second question: Where might I find a simple example that I could learn from to > graft a fact-base to a database in JESS? Whereas the interplay of database, backward chaining, and all in the FSPF is subtle and a bit complicated, just getting RDBMS data into Jess is not. Basically, in one form or another, all such solutions would query your database using JDBC, craft JavaBeans or jess.Fact objects, and add them to Jess's working memory. It's not complicated. See, for example, section 18.2 of Jess in Action; there's an example on page 312 (listing 18.1) where facts are being created based on data in a 2D String array. Just imagine using a ResultSet instead of that String[][], and you've got an example right there. > I hope my questions are understandable and not too > bothersome. Thank you for your time! You're welcome. --------------------------------------------------------- Ernest Friedman-Hill Science and Engineering PSEs Phone: (925) 294-2154 Sandia National Labs FAX: (925) 294-2234 PO Box 969, MS 9012 [EMAIL PROTECTED] Livermore, CA 94550 http://herzberg.ca.sandia.gov -------------------------------------------------------------------- To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' in the BODY of a message to [EMAIL PROTECTED], NOT to the list (use your own address!) List problems? Notify [EMAIL PROTECTED] --------------------------------------------------------------------
