JESS uses hashtree, so I suspect it the current custom HashTable is better than the type of HashTree that JESS uses
peter On 12/18/06, Mark Proctor <[EMAIL PROTECTED]> wrote:
I wonder if the overhead of a btree, btw have you seen htrees, compared to hashmap is worth while, I expect it is as join ordering can make a big difference. Mark Edson Tirelli wrote: > Mark, > > The approach I was looking into that time was not feasible because > we used to keep order of asserted fact/tuples on a node basis. With > the core changes you made in 3.1, we can implement range ordering by > replacing the current hashmap index for a tree index. No need for > training data, in my understanding. > Maybe we will need a composed index approach to work some cases, but > the general solution idea is simple. > > []s > Edson > > Mark Proctor wrote: > >> Actually I was just thinking about some stuff Edson has done. With >> solvers we know the available data and ranges, right? We can use this >> to order indexes, I know this was something Edson looked into - but >> without training data, we couldn't make it worth while - same >> for custom indexing. So we can start to incorporate those to get >> faster joins for known data sets. >> >> Mark >> Geoffrey De Smet wrote: >> >>> The more I learn from JCHS (or prolog for that matter), >>> the more I am starting to think that this is a different way of >>> solving. >>> >>> 1) JCHS/prolog looks like (or is) declarative solving. >>> >>> 2) Taseree is actually more hybrid, the general idea behind it is: >>> - Drools (declarative programming) is very easy for evaluation >>> but very difficult for solving. >>> - Local/tabu search (procedural programming) is easy for solving >>> but difficult for evaluation. >>> >>> >>> Both have it's disadvantages and advantages, for example: >>> Local search is generally faster but doesn't recognize the optimal >>> solution. >>> >>> To me it seems they are both interesting to implement, >>> there must be some common ground too. >>> We should hold a conference call about it this weekend? >>> >>> It would be a good idea to compare JCHS and Taseree on a couple of >>> problems, like the tt problem: >>> http://mat.gsia.cmu.edu/TOURN/ >>> >> >> >> --------------------------------------------------------------------- >> To unsubscribe from this list please visit: >> >> http://xircles.codehaus.org/manage_email >> >> > > --------------------------------------------------------------------- To unsubscribe from this list please visit: http://xircles.codehaus.org/manage_email
