it.unibz.inf.ontop.iq.executor.join

Class FunctionalDependencyUnificationExecutor

java.lang.Object

it.unibz.inf.ontop.iq.executor.join.SelfJoinLikeExecutor

it.unibz.inf.ontop.iq.executor.join.RedundantSelfJoinExecutor

it.unibz.inf.ontop.iq.executor.join.FunctionalDependencyUnificationExecutor

All Implemented Interfaces:

InnerJoinExecutor, NodeCentricExecutor<InnerJoinNode,NodeCentricOptimizationResults<InnerJoinNode>,InnerJoinOptimizationProposal>, ProposalExecutor<InnerJoinOptimizationProposal,NodeCentricOptimizationResults<InnerJoinNode>>, SimpleNodeCentricExecutor<InnerJoinNode,InnerJoinOptimizationProposal>

public class FunctionalDependencyUnificationExecutor
extends RedundantSelfJoinExecutor

Focuses on functional dependencies that are not unique constraints. Uses them to unify some terms (a functional dependency is generating equalities) Self-join elimination is done LATER by the SelfJoinSameTermIQOptimizer, by taking advantage of the unified variables. NB: Was having before some logic for removing some redundant join, but was not safe to apply when cardinality matters. The code has only been superficially simplified so some logic that is not needed anymore may still remain.

Nested Class Summary

Nested classes/interfaces inherited from class it.unibz.inf.ontop.iq.executor.join.SelfJoinLikeExecutor

SelfJoinLikeExecutor.AtomUnificationException, SelfJoinLikeExecutor.ConcreteProposal, SelfJoinLikeExecutor.PredicateLevelProposal

Method Summary

Modifier and Type	Method and Description
protected Optional<SelfJoinLikeExecutor.PredicateLevelProposal>	proposePerPredicate(InnerJoinNode joinNode, it.unibz.inf.ontop.com.google.common.collect.ImmutableCollection<ExtensionalDataNode> initialNodes, RelationDefinition relation, it.unibz.inf.ontop.com.google.common.collect.ImmutableList<Variable> priorityVariables, IntermediateQuery query)

Methods inherited from class it.unibz.inf.ontop.iq.executor.join.RedundantSelfJoinExecutor

apply, createConcreteProposal

Methods inherited from class it.unibz.inf.ontop.iq.executor.join.SelfJoinLikeExecutor

extractDataNodes, extractSubstitutions, mergeSubstitutions, prioritizeVariables, updateJoinNodeAndPropagateSubstitution

Methods inherited from class java.lang.Object

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

Method Detail

proposePerPredicate

protected Optional<SelfJoinLikeExecutor.PredicateLevelProposal> proposePerPredicate(InnerJoinNode joinNode,
                                                                                    it.unibz.inf.ontop.com.google.common.collect.ImmutableCollection<ExtensionalDataNode> initialNodes,
                                                                                    RelationDefinition relation,
                                                                                    it.unibz.inf.ontop.com.google.common.collect.ImmutableList<Variable> priorityVariables,
                                                                                    IntermediateQuery query)
                                                                             throws SelfJoinLikeExecutor.AtomUnificationException

Specified by:

proposePerPredicate in class RedundantSelfJoinExecutor

Throws:

SelfJoinLikeExecutor.AtomUnificationException