Class StatementGroupAndJoinOptimizer

java.lang.Object

org.eclipse.rdf4j.query.algebra.helpers.AbstractSimpleQueryModelVisitor<OptimizationException>

org.eclipse.rdf4j.federated.optimizer.StatementGroupAndJoinOptimizer

All Implemented Interfaces:

FedXOptimizer, QueryModelVisitor<OptimizationException>

public class StatementGroupAndJoinOptimizer
extends AbstractSimpleQueryModelVisitor<OptimizationException>
implements FedXOptimizer

Optimizer with the following tasks: 1. Group ExclusiveStatement into ExclusiveGroup 2. Adjust the join order using DefaultFedXCostModel

Author:

as

Field Summary

Fields

Modifier and Type	Field	Description
protected final QueryInfo	queryInfo

Constructor Summary

Constructors

Constructor	Description
StatementGroupAndJoinOptimizer(QueryInfo queryInfo, FedXCostModel costModel)

Method Summary

Modifier and Type	Method	Description
protected double	estimateCost(TupleExpr tupleExpr, Set<String> joinVars)
protected List<TupleExpr>	formGroups(List<TupleExpr> originalArgs)	Group ExclusiveStatements having the same source into an ExclusiveGroup.
void	meet(Service tupleExpr)
protected void	meetNJoin(NJoin node)
void	meetOther(QueryModelNode node)
void	optimize(TupleExpr tupleExpr)	Optimize the provided tuple expression
protected List<TupleExpr>	optimizeJoinOrder(List<TupleExpr> joinArgs)	Join Order Optimizer Group -> Statements according to number of free Variables Additional Heuristics: - ExclusiveGroups are cheaper than any other subquery - owned statements are cheaper if they have a single free variable

Methods inherited from class AbstractSimpleQueryModelVisitor

meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meetBinaryTupleOperator, meetBinaryValueOperator, meetCompareSubQueryValueOperator, meetNAryValueOperator, meetSubQueryValueOperator, meetUnaryTupleOperator, meetUnaryValueOperator, meetUnsupported, meetUpdateExpr

Modifier and Type	Method	Description
void	meet(Add node)
void	meet(AggregateFunctionCall node)
void	meet(And node)
void	meet(ArbitraryLengthPath node)
void	meet(Avg node)
void	meet(BindingSetAssignment node)
void	meet(BNodeGenerator node)
void	meet(Bound node)
void	meet(Clear node)
void	meet(Coalesce node)
void	meet(Compare node)
void	meet(CompareAll node)
void	meet(CompareAny node)
void	meet(Copy node)
void	meet(Count node)
void	meet(Create node)
void	meet(Datatype node)
void	meet(DeleteData node)
void	meet(DescribeOperator node)
void	meet(Difference node)
void	meet(Distinct node)
void	meet(EmptySet node)
void	meet(Exists node)
void	meet(Extension node)
void	meet(ExtensionElem node)
void	meet(Filter node)
void	meet(FunctionCall node)
void	meet(Group node)
void	meet(GroupConcat node)
void	meet(GroupElem node)
void	meet(If node)
void	meet(In node)
void	meet(InsertData node)
void	meet(Intersection node)
void	meet(IRIFunction node)
void	meet(IsBNode node)
void	meet(IsLiteral node)
void	meet(IsNumeric node)
void	meet(IsResource node)
void	meet(IsURI node)
void	meet(Join node)
void	meet(Label node)
void	meet(Lang node)
void	meet(LangMatches node)
void	meet(LeftJoin node)
void	meet(ListMemberOperator node)
void	meet(Load node)
void	meet(LocalName node)
void	meet(MathExpr node)
void	meet(Max node)
void	meet(Min node)
void	meet(Modify node)
void	meet(Move node)
void	meet(MultiProjection node)
void	meet(Namespace node)
void	meet(Not node)
void	meet(Or node)
void	meet(Order node)
void	meet(OrderElem node)
void	meet(Projection node)
void	meet(ProjectionElem node)
void	meet(ProjectionElemList node)
void	meet(QueryRoot node)
void	meet(Reduced node)
void	meet(Regex node)
void	meet(SameTerm node)
void	meet(Sample node)
void	meet(SingletonSet node)
void	meet(Slice node)
void	meet(StatementPattern node)
void	meet(Str node)
void	meet(Sum node)
void	meet(TripleRef node)
void	meet(Union node)
void	meet(ValueConstant node)
void	meet(ValueExprTripleRef node)
void	meet(Var node)
void	meet(ZeroLengthPath node)
protected void	meetBinaryTupleOperator(BinaryTupleOperator node)	Method called by all meet methods with a BinaryTupleOperator node as argument.
protected void	meetBinaryValueOperator(BinaryValueOperator node)	Method called by all meet methods with a BinaryValueOperator node as argument.
protected void	meetCompareSubQueryValueOperator(CompareSubQueryValueOperator node)	Method called by all meet methods with a CompareSubQueryValueOperator node as argument.
protected void	meetNAryValueOperator(NAryValueOperator node)	Method called by all meet methods with a NAryValueOperator node as argument.
protected void	meetSubQueryValueOperator(SubQueryValueOperator node)	Method called by all meet methods with a SubQueryValueOperator node as argument.
protected void	meetUnaryTupleOperator(UnaryTupleOperator node)	Method called by all meet methods with a UnaryTupleOperator node as argument.
protected void	meetUnaryValueOperator(UnaryValueOperator node)	Method called by all meet methods with a UnaryValueOperator node as argument.
void	meetUnsupported(QueryModelNode node)
protected void	meetUpdateExpr(UpdateExpr node)	Method called by all meet methods with a UpdateExpr node as argument.

Methods inherited from class Object

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

Field Details

queryInfo

protected final QueryInfo queryInfo

Constructor Details

StatementGroupAndJoinOptimizer

public StatementGroupAndJoinOptimizer(QueryInfo queryInfo,
 FedXCostModel costModel)

Method Details

optimize

public void optimize(TupleExpr tupleExpr)

Description copied from interface: FedXOptimizer

Optimize the provided tuple expression

Specified by:

optimize in interface FedXOptimizer

Parameters:

tupleExpr -

meet

public void meet(Service tupleExpr)

Specified by:

meet in interface QueryModelVisitor<OptimizationException>

Overrides:

meet in class AbstractSimpleQueryModelVisitor<OptimizationException>

meetOther

public void meetOther(QueryModelNode node)

Specified by:

meetOther in interface QueryModelVisitor<OptimizationException>

Overrides:

meetOther in class AbstractSimpleQueryModelVisitor<OptimizationException>

meetNJoin

protected void meetNJoin(NJoin node)

formGroups

protected List<TupleExpr> formGroups(List<TupleExpr> originalArgs)

Group ExclusiveStatements having the same source into an ExclusiveGroup.

Parameters:

originalArgs -

Returns:

the new (potentially grouped) join arguments. If empty, the join will not produce any results.

optimizeJoinOrder

protected List<TupleExpr> optimizeJoinOrder(List<TupleExpr> joinArgs)

Join Order Optimizer Group -> Statements according to number of free Variables Additional Heuristics: - ExclusiveGroups are cheaper than any other subquery - owned statements are cheaper if they have a single free variable

Parameters:

joinArgs -

Returns:

estimateCost

protected double estimateCost(TupleExpr tupleExpr,
 Set<String> joinVars)