Class InfAtomicFOQueryEvaluator

java.lang.Object

fr.inria.rules.integraal.query_evaluation.atomic.InfAtomicFOQueryEvaluator

All Implemented Interfaces:

FOQueryEvaluator<Atom, MaterializedData>, QueryEvaluator<FOQuery<? extends Atom>, MaterializedData>

public class InfAtomicFOQueryEvaluator
extends Object
implements FOQueryEvaluator<Atom, MaterializedData>

Evaluates an Atomic FOQuery using the ≲ condition given from a rule compilation

Given a factbase F = {B, C, D} an atomic query A The ≲-homomorphism(A, F) ≡ B ≲ A C ≲ A D ≲ A

We could also reduce the size of F by only taking into account atoms with a compatible predicate.

Author:

Florent Tornil

Constructor Summary

Constructors

Constructor	Description
InfAtomicFOQueryEvaluator(RuleCompilation compilation)	Constructor using a compilation

Method Summary

Modifier and Type	Method	Description
Stream<Substitution>	evaluate(FOQuery<? extends Atom> query, MaterializedData materializedData, Collection<Variable> vars, Substitution preHomomorphism)	Evaluates a first-order query against a data source.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface FOQueryEvaluator

prepareQuery, prepareQuery

Methods inherited from interface QueryEvaluator

countAnswers, countHomomorphism, evaluate, evaluate, existAnswer, existAnswer, existHomomorphism, existHomomorphism, homomorphism, homomorphism, postprocessResult, postprocessResult

Constructor Details

InfAtomicFOQueryEvaluator

public InfAtomicFOQueryEvaluator(RuleCompilation compilation)

Constructor using a compilation

Parameters:

compilation - the rule compilation to compute homomorphisms according to

Method Details

evaluate

public Stream<Substitution> evaluate(FOQuery<? extends Atom> query,
 MaterializedData materializedData,
 Collection<Variable> vars,
 Substitution preHomomorphism)

Description copied from interface: FOQueryEvaluator

Evaluates a first-order query against a data source.

Specified by:

evaluate in interface FOQueryEvaluator<Atom, MaterializedData>

Specified by:

evaluate in interface QueryEvaluator<FOQuery<? extends Atom>, MaterializedData>

Parameters:

query - the query to evaluate

materializedData - the data source against which the query is evaluated

vars - variables constrained to constant answers

preHomomorphism - a partial substitution to extend

Returns:

a stream of substitutions answering the query