com.bigdata.rdf.sparql.ast.optimizers

Class ASTRangeCountOptimizer

java.lang.Object

com.bigdata.rdf.sparql.ast.optimizers.AbstractJoinGroupOptimizer

com.bigdata.rdf.sparql.ast.optimizers.ASTRangeCountOptimizer

All Implemented Interfaces:

IASTOptimizer

public class ASTRangeCountOptimizer
extends AbstractJoinGroupOptimizer
implements IASTOptimizer

Attach range counts to all statement patterns in the query.

Author:

mikepersonick

Constructor Summary

Constructors

Constructor and Description
ASTRangeCountOptimizer()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	attachRangeCounts(AST2BOpContext ctx, List<StatementPatternNode> spNodes, IBindingSet exogenousBindings, int nrExogeneousBindings) Use the SPORelation from the database to grab the appropriate range counts for the StatementPatternNodes.
protected void	estimateCardinalities(StatementPatternNode sp, IV<?,?> s, IV<?,?> p, IV<?,?> o, IV<?,?> c, AST2BOpContext ctx, int exogenousBindingsAdjustmentFactor)
protected void	estimateCardinality(StatementPatternNode sp, AST2BOpContext ctx, IBindingSet exogenousBindings, int nrExogeneousBindings) For testing purposes we can override this method.
protected static IV	getIV(TermNode term, IBindingSet exogenousBindings, AtomicBoolean usesExogeneousBinding) Helper method grabs the IV out of the TermNode, doing the appropriate NULL and constant/var checks.
protected void	optimizeJoinGroup(AST2BOpContext ctx, StaticAnalysis sa, IBindingSet[] bSets, JoinGroupNode group) Optimize the join group.

Methods inherited from class com.bigdata.rdf.sparql.ast.optimizers.AbstractJoinGroupOptimizer

optimize

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.bigdata.rdf.sparql.ast.optimizers.IASTOptimizer

optimize

Constructor Detail

ASTRangeCountOptimizer

public ASTRangeCountOptimizer()

Method Detail

optimizeJoinGroup

protected void optimizeJoinGroup(AST2BOpContext ctx,
                     StaticAnalysis sa,
                     IBindingSet[] bSets,
                     JoinGroupNode group)

Optimize the join group.

Specified by:

optimizeJoinGroup in class AbstractJoinGroupOptimizer

attachRangeCounts

protected void attachRangeCounts(AST2BOpContext ctx,
                     List<StatementPatternNode> spNodes,
                     IBindingSet exogenousBindings,
                     int nrExogeneousBindings)

Use the SPORelation from the database to grab the appropriate range counts for the StatementPatternNodes. Only tries to attach them if the annotation AST2BOpBase.Annotations.ESTIMATED_CARDINALITY is not already attached to the node. This makes it possible to write unit tests without real data.

estimateCardinality

protected void estimateCardinality(StatementPatternNode sp,
                       AST2BOpContext ctx,
                       IBindingSet exogenousBindings,
                       int nrExogeneousBindings)

For testing purposes we can override this method.

Parameters:

sp -

db -

exogenousBindings -

estimateCardinalities

protected void estimateCardinalities(StatementPatternNode sp,
                         IV<?,?> s,
                         IV<?,?> p,
                         IV<?,?> o,
                         IV<?,?> c,
                         AST2BOpContext ctx,
                         int exogenousBindingsAdjustmentFactor)

getIV

protected static IV getIV(TermNode term,
       IBindingSet exogenousBindings,
       AtomicBoolean usesExogeneousBinding)

Helper method grabs the IV out of the TermNode, doing the appropriate NULL and constant/var checks.

Parameters:

term -

exogenousBindings - The externally given bindings (optional).