org.janusgraph.graphdb.query.index

Class BruteForceIndexSelectionStrategy

java.lang.Object

org.janusgraph.graphdb.query.index.AbstractIndexSelectionStrategy

org.janusgraph.graphdb.query.index.BruteForceIndexSelectionStrategy

All Implemented Interfaces:

IndexSelectionStrategy

public class BruteForceIndexSelectionStrategy
extends AbstractIndexSelectionStrategy

Author:

Florian Grieskamp (Florian.Grieskamp@gdata.de)

Nested Class Summary

Nested classes/interfaces inherited from interface org.janusgraph.graphdb.query.index.IndexSelectionStrategy

IndexSelectionStrategy.SelectedIndexQuery

Field Summary

Fields

Modifier and Type	Field and Description
static String	NAME

Constructor Summary

Constructors

Constructor and Description
BruteForceIndexSelectionStrategy(Configuration config)

Method Summary

Modifier and Type	Method and Description
IndexSelectionStrategy.SelectedIndexQuery	selectIndices(Set<IndexType> rawCandidates, MultiCondition<JanusGraphElement> conditions, Set<Condition> coveredClauses, OrderList orders, IndexSerializer serializer) Determine the best jointIndexQuery by enumerating all possibilities with exponential time complexity.

Methods inherited from class org.janusgraph.graphdb.query.index.AbstractIndexSelectionStrategy

addToJointQuery, createIndexCandidate, createIndexRawCandidates, getConditionBasicScore, getIndexTypeScore, selectIndices

Methods inherited from class java.lang.Object

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

Field Detail

NAME

public static final String NAME

See Also:

Constant Field Values

Constructor Detail

BruteForceIndexSelectionStrategy

public BruteForceIndexSelectionStrategy(Configuration config)

Method Detail

selectIndices

public IndexSelectionStrategy.SelectedIndexQuery selectIndices(Set<IndexType> rawCandidates,
                                                               MultiCondition<JanusGraphElement> conditions,
                                                               Set<Condition> coveredClauses,
                                                               OrderList orders,
                                                               IndexSerializer serializer)

Determine the best jointIndexQuery by enumerating all possibilities with exponential time complexity. Similar to Weighted Set Cover problem, to find the best choice is NP-Complete, so we should be careful that the problem size MUST be small, otherwise it is more recommended to use an approximation algorithm.