Abstract: A program stored on non-transitory computer-readable storage medium executes a method of evaluating a graph over a query. Decomposition instructions decompose the query into a plurality of subqueries. Evaluation instructions evaluate a subquery of the plurality of subqueries and generate a substitution multiset representing a result of the evaluation of the subquery. Filtration instructions or expansion instructions may operate upon the generated substitution set before passing the substitution set to a next subquery to be evaluated. The filtration instructions identify one or more mappings in the substitution multiset that cannot be safely passed to the second subquery and delete the identified one or more mappings from the substitution multiset. The expansion instructions determine, in a case where the subquery is operated upon by a non-distributive query operator, an expansion of the substitution multiset based at least on adding one or more new substitutions to the substitution multiset.

Abstract: A computer-implemented method of providing a materialisation of a set of logical rules on a logical database comprising a set of logical facts. Each of a plurality of parallel processing threads performs the following steps. A logical fact that has not previously been received by any thread is received by the thread. By applying any of the logical rules to the received logical fact and/or any of the logical facts received by any thread prior to the received logical fact, the thread determines whether a new logical fact is implied, and if so the new logical fact is added to the set of logical facts. The thread then repeats the above steps on any further logical facts in the set of logical facts that have not previously been received by any thread. When all threads are waiting for a new logical fact, the method has completed.

Abstract: A program stored on non-transitory computer-readable storage medium executes a method of evaluating a graph over a query. Decomposition instructions decompose the query into a plurality of subqueries. Evaluation instructions evaluate a subquery of the plurality of subqueries and generate a substitution multiset representing a result of the evaluation of the subquery. Filtration instructions or expansion instructions may operate upon the generated substitution set before passing the substitution set to a next subquery to be evaluated. The filtration instructions identify one or more mappings in the substitution multiset that cannot be safely passed to the second subquery and delete the identified one or more mappings from the substitution multiset. The expansion instructions determine, in a case where the subquery is operated upon by a non-distributive query operator, an expansion of the substitution multiset based at least on adding one or more new substitutions to the substitution multiset.

Abstract: A program stored on non-transitory computer-readable storage medium executes a method of evaluating a graph over a query. Decomposition instructions decompose the query into a plurality of subqueries. Evaluation instructions evaluate a subquery of the plurality of subqueries and generate a substitution multiset representing a result of the evaluation of the subquery. Filtration instructions or expansion instructions may operate upon the generated substitution set before passing the substitution set to a next subquery to be evaluated. The filtration instructions identify one or more mappings in the substitution multiset that cannot be safely passed to the second subquery and delete the identified one or more mappings from the substitution multiset. The expansion instructions determine, in a case where the subquery is operated upon by a non-distributive query operator, an expansion of the substitution multiset based at least on adding one or more new substitutions to the substitution multiset.

Abstract: A computer-implemented method of providing a materialisation of a set of logical rules on a logical database comprising a set of logical facts. Each of a plurality of parallel processing threads performs the following steps. A logical fact that has not previously been received by any thread is received by the thread. By applying any of the logical rules to the received logical fact and/or any of the logical facts received by any thread prior to the received logical fact, the thread determines whether a new logical fact is implied, and if so the new logical fact is added to the set of logical facts. The thread then repeats the above steps on any further logical facts in the set of logical facts that have not previously been received by any thread. When all threads are waiting for a new logical fact, the method has completed.

Abstract: A computer-implemented method of providing a materialisation of a set of logical rules on a logical database comprising a set of logical facts. Each of a plurality of parallel processing threads performs the following steps. A logical fact that has not previously been received by any thread is received by the thread. By applying any of the logical rules to the received logical fact and/or any of the logical facts received by any thread prior to the received logical fact, the thread determines whether a new logical fact is implied, and if so the new logical fact is added to the set of logical facts. The thread then repeats the above steps on any further logical facts in the set of logical facts that have not previously been received by any thread. When all threads are waiting for a new logical fact, the method has completed.

Abstract: A computer-implemented method of providing a materialisation of a set of logical rules on a logical database comprising a set of logical facts. Each of a plurality of parallel processing threads performs the following steps. A logical fact that has not previously been received by any thread is received by the thread. By applying any of the logical rules to the received logical fact and/or any of the logical facts received by any thread prior to the received logical fact, the thread determines whether a new logical fact is implied, and if so the new logical fact is added to the set of logical facts. The thread then repeats the above steps on any further logical facts in the set of logical facts that have not previously been received by any thread. When all threads are waiting for a new logical fact, the method has completed.