com.bigdata.rdf.sparql.ast

Interface IReorderableNode

All Superinterfaces:

BOp, Cloneable, IBindingProducerNode, IGroupMemberNode, IPropertySet, IQueryNode, IVariableBindingRequirements, Serializable

All Known Implementing Classes:

ArbitraryLengthPathNode, BindingsClause, PropertyPathUnionNode, StatementPatternNode, UnionNode

public interface IReorderableNode
extends IGroupMemberNode, IBindingProducerNode, BOp

Interface for things which can be re-ordered by the static join optimizer. Currently limited to StatementPatternNodes and some instances of ArbitraryLengthPathNodes (those with a single statement pattern inside).

Nested Class Summary

Nested classes/interfaces inherited from interface com.bigdata.rdf.sparql.ast.IQueryNode

IQueryNode.Annotations

Field Summary

Fields inherited from interface com.bigdata.bop.BOp

NOANNS, NOARGS

Method Summary

Methods

Modifier and Type	Method and Description
long	getEstimatedCardinality(StaticOptimizer opt) Return the estimated cardinality - either the range count of a statement pattern or some computed estimated cardinality for a join group.
boolean	isReorderable() The decision about whether to re-order can no longer be made simply by examining the type - individual instances of a particular type may or may not be reorderable.

Methods inherited from interface com.bigdata.rdf.sparql.ast.IGroupMemberNode

getContext, getParent, getParentGraphPatternGroup, getParentJoinGroup, setParent

Methods inherited from interface com.bigdata.rdf.sparql.ast.IVariableBindingRequirements

getDesiredBound, getRequiredBound

Methods inherited from interface com.bigdata.rdf.sparql.ast.IQueryNode

toString

Methods inherited from interface com.bigdata.bop.BOp

annotations, argIterator, args, arity, clone, get, getEvaluationContext, getId, getProperty, getRequiredProperty, isController, setProperty, toArray, toArray, toShortString, toString

Methods inherited from interface cutthecrap.utils.striterators.IPropertySet

getProperty

Method Detail

isReorderable

boolean isReorderable()

The decision about whether to re-order can no longer be made simply by examining the type - individual instances of a particular type may or may not be reorderable.

getEstimatedCardinality

long getEstimatedCardinality(StaticOptimizer opt)

Return the estimated cardinality - either the range count of a statement pattern or some computed estimated cardinality for a join group.

Parameters:

opt - This optimizer can be used to help work out the estimate