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

org.eclipse.rdf4j.federated.optimizer.TripleRefJoinOptimizer

All Implemented Interfaces:: FedXOptimizer, QueryModelVisitor<OptimizationException>

public class TripleRefJoinOptimizer extends AbstractSimpleQueryModelVisitor<OptimizationException> implements FedXOptimizer

Optimizer that groups TripleRefStatementPattern nodes with co-located StatementPattern nodes into TripleRefJoinGroup instances, enabling efficient federated evaluation of RDF 1.2 reification patterns.

The optimizer visits every NJoin in the query tree (depth-first) and looks for pairs of a TripleRefStatementPattern and one or more plain StatementPatterns that share the same unbound subject variable. Matched patterns are collapsed into a single TripleRefJoinGroup that can be sent as one request to the owning endpoints.

Author:

Andreas Schwarte

See Also:

Field Summary

Fields

Modifier and Type

Field

Description

protected final QueryInfo

queryInfo
Constructor Summary

Constructors

Constructor

Description

TripleRefJoinOptimizer(QueryInfo queryInfo)
Method Summary

Modifier and Type

Method

Description

protected List<TupleExpr>

formGroups(List<TupleExpr> originalArgs)

Group TripleRefStatementPattern and StatementPattern having the same subject variable into a TripleRefJoinGroup.

void

meet(Service tupleExpr)

protected void

meetNJoin(NJoin node)

void

meetOther(QueryModelNode node)

void

optimize(TupleExpr tupleExpr)

Optimize the provided tuple expression

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, 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(HasLang node)

void

meet(HasLangDir 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(IsTriple node)

void

meet(IsURI node)

void

meet(Join node)

void

meet(Label node)

void

meet(Lang node)

void

meet(LangDir node)

void

meet(LangMatches node)

void

meet(Lateral 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(StrLangDir 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
- TripleRefJoinOptimizer
  
  public TripleRefJoinOptimizer(QueryInfo queryInfo)
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 TripleRefStatementPattern and StatementPattern having the same subject variable into a TripleRefJoinGroup.
  Assumption: a shared unbound subject variable is treated as a sufficient co-location signal. In RDF 1.2 reification patterns the subject linking the outer statement to its triple term is typically a blank node that is local to a single dataset (and therefore to a single endpoint). No additional source-exclusivity check is performed.
  
  Parameters:
  
  originalArgs - the join arguments to group
  
  Returns:
  
  the new (potentially grouped) join arguments. If empty, the join will not produce any results.

Class TripleRefJoinOptimizer

Field Summary

Constructor Summary

Method Summary

Methods inherited from class AbstractSimpleQueryModelVisitor

Methods inherited from class Object

Field Details

queryInfo

Constructor Details

TripleRefJoinOptimizer

Method Details

optimize

meet

meetOther

meetNJoin

formGroups