Class CFRBasedCostFunctionForPlan

java.lang.Object

se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.costmodel.CFRBasedCostFunctionForPlan

All Implemented Interfaces:

CostFunctionForPlan

Direct Known Subclasses:

CFRBasedParallelismCostFunctionForPlan

public class CFRBasedCostFunctionForPlan
extends Object
implements CostFunctionForPlan

Generic implementation of CostFunctionForPlan that can be used for any cost function that is defined as the sum of operator-specific cost values for all operators in the plan. This implementation uses recursion to first determine the cost values for subplans, and to determines the operator-specific cost values the implementation uses a CostFunctionForRootOp.

Field Summary

Fields

Modifier and Type	Field	Description
protected final CostFunctionForRootOp	costFctForRoot

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	CFRBasedCostFunctionForPlan(CostFunctionForRootOp costFctForRoot)

Method Summary

Modifier and Type	Method	Description
CompletableFuture<Integer>	aggregateValueForAllSubPlans(Set<PhysicalPlan> visitedPlan, CompletableFuture<Integer> futureForRoot, PhysicalPlan plan)
CompletableFuture<Integer>	initiateCostEstimation(Set<PhysicalPlan> visitedPlans, PhysicalPlan plan)	A function for estimating the cost of a plan.

Methods inherited from class java.lang.Object

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

Field Details

costFctForRoot

protected final CostFunctionForRootOp costFctForRoot

Constructor Details

CFRBasedCostFunctionForPlan

protected CFRBasedCostFunctionForPlan(CostFunctionForRootOp costFctForRoot)

Method Details

initiateCostEstimation

public CompletableFuture<Integer> initiateCostEstimation(Set<PhysicalPlan> visitedPlans,
 PhysicalPlan plan)

Description copied from interface: CostFunctionForPlan

A function for estimating the cost of a plan.

Specified by:

initiateCostEstimation in interface CostFunctionForPlan

Parameters:

visitedPlans - : Record a set of sub-plans (of plan) that have been visited during the cost estimation. This set can be used for checking if a subplan has been visited or not.

aggregateValueForAllSubPlans

public CompletableFuture<Integer> aggregateValueForAllSubPlans(Set<PhysicalPlan> visitedPlan,
 CompletableFuture<Integer> futureForRoot,
 PhysicalPlan plan)