Package edu.harvard.seas.pl.abcdatalog.engine.topdown

package edu.harvard.seas.pl.abcdatalog.engine.topdown
This package contains implementations of standard top-down Datalog evaluation algorithms. The implementations here should be viewed as less-trustworthy than the bottom-up implementations in edu.harvard.seas.pl.abcdatalog.engine.bottomup.sequential and edu.harvard.seas.pl.abcdatalog.engine.bottomup.concurrent.
  • Classes
    Class
    Description
    AbstractQsqEngine
    A Datalog engine that uses a variant of the query-subquery evaluation method.
    AdornedAtom
    An adorned atom (i.e., an atom where every argument is marked as either bound or free).
    AdornedClause
    An adorned clause (i.e., a Horn clause where every atom is itself adorned).
    AdornedPredicateSym
    An adorned predicate symbol.
    IterativeQsqEngine
    A Datalog evaluation engine that uses an iterative version of the query-subquery top-down technique.
    MstEngine
    A Datalog evaluation engine that uses the magic set transformation technique.
    QsqSupRelation
    A supplementary relation used in QSQ evaluation.
    QsqTemplate
    A template containing the attribute schemata of the supplementary relations for a given rule in QSQ evaluation.
    RecursiveQsqEngine
    A Datalog evaluation engine that uses a recursive version of the query-subquery top-down technique.
    Relation
    A relation, i.e., a set of tuples of a fixed arity with an associated attribute schema of the same arity.
    TermSchema
    A list of terms of fixed arity representing the attribute schema for a relation of the same arity (i.e., the 2nd term in the list is the attribute for the 2nd "column" in the relation).
    Tuple
    A tuple of terms, i.e., an ordered list of fixed arity.