Package se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.simple

Class CardinalityBasedGreedyJoinPlanOptimizerImpl

java.lang.Object

se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.simple.JoinPlanOptimizerBase

se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.simple.CardinalityBasedGreedyJoinPlanOptimizerImpl

All Implemented Interfaces:

JoinPlanOptimizer

public class CardinalityBasedGreedyJoinPlanOptimizerImpl
extends JoinPlanOptimizerBase

This class implements a query optimizer[1] that builds left-deep query plans, for which it uses a greedy approach to determine the join order based on cardinality estimation, and then choose physical algorithm according to the estimated number of request to execute the join. [1] Heling, Lars, and Maribel Acosta. "Federated SPARQL query processing over heterogeneous linked data fragments." Proceedings of the ACM Web Conference 2022.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	CardinalityBasedGreedyJoinPlanOptimizerImpl.GreedyConstructionAlgorithm

Nested classes/interfaces inherited from class se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.simple.JoinPlanOptimizerBase

JoinPlanOptimizerBase.EnumerationAlgorithm

Field Summary

Fields

Modifier and Type	Field	Description
protected final FederationAccessManager	fedAccessMgr

Constructor Summary

Constructors

Constructor	Description
CardinalityBasedGreedyJoinPlanOptimizerImpl(QueryProcContext ctx)

Method Summary

Modifier and Type	Method	Description
JoinPlanOptimizerBase.EnumerationAlgorithm	initializeEnumerationAlgorithm(List<PhysicalPlan> subplans)

Methods inherited from class se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.simple.JoinPlanOptimizerBase

determineJoinPlan

Methods inherited from class java.lang.Object

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

Methods inherited from interface se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.simple.JoinPlanOptimizer

determineJoinPlan

Field Details

fedAccessMgr

protected final FederationAccessManager fedAccessMgr

Constructor Details

CardinalityBasedGreedyJoinPlanOptimizerImpl

public CardinalityBasedGreedyJoinPlanOptimizerImpl(QueryProcContext ctx)

Method Details

initializeEnumerationAlgorithm

public JoinPlanOptimizerBase.EnumerationAlgorithm initializeEnumerationAlgorithm(List<PhysicalPlan> subplans)

Specified by:

initializeEnumerationAlgorithm in class JoinPlanOptimizerBase