36. A case-based reasoning system, comprising a rule base having a plurality of inferential rules; a case base having a plurality of exemplar cases; a data base having a plurality of data records having a plurality of data items external to a set of facts in a problem template and external to a set of derived facts concluded from said set of facts; an inference engine comprising means for performing case-based reasoning steps on said cases and said problem template, and comprising means for performing rule-based reasoning steps on said data items external to said set of facts in said problem template and external to said derived facts using said rules in a unified automated reasoning system; wherein said inference engine comprises means for matching said problem template having a set of facts to said case base; and means for applying said rules to said cases, said data items in said data records external to said set of facts in said problem template and external to said derived facts, and said facts in said problem template; and means for performing a method of matching a problem template to a case base, said method comprising the steps of first generating a case location in a hash table in response to at least one attribute-value pair for each case in said case base; recording at least one pointer to a case in each one of said case locations; second generating at least one problem locationin said hash table in response to at least one problem attribute-value pair; and selecting among a set of cases pointed to by said pointers found in said hash table at said at least one problem location.
36. A case-based reasoning system, comprising a rule base having a plurality of inferential rules; a case base having a plurality of exemplar cases; a data base having a plurality of data records having a plurality of data items external to a set of facts in a problem template and external to a set of derived facts concluded from said set of facts; an inference engine comprising means for performing case-based reasoning steps on said cases and said problem template, and comprising means for performing rule-based reasoning steps on said data items external to said set of facts in said problem template and external to said derived facts using said rules in a unified automated reasoning system; wherein said inference engine comprises means for matching said problem template having a set of facts to said case base; and means for applying said rules to said cases, said data items in said data records external to said set of facts in said problem template and external to said derived facts, and said facts in said problem template; and means for performing a method of matching a problem template to a case base, said method comprising the steps of first generating a case location in a hash table in response to at least one attribute-value pair for each case in said case base; recording at least one pointer to a case in each one of said case locations; second generating at least one problem locationin said hash table in response to at least one problem attribute-value pair; and selecting among a set of cases pointed to by said pointers found in said hash table at said at least one problem location. 37. A system as in claim 36, wherein said first generating step comprises applying a hash function to said at least one attribute-value pair.