Package se.liu.ida.hefquin.engine.queryplan.executable.impl.ops

Class ExecOpParallelMultiwayLeftJoin

java.lang.Object

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBase

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.ExecOpParallelMultiwayLeftJoin

All Implemented Interfaces:

StatsProvider, ExecutableOperator, UnaryExecutableOp

public class ExecOpParallelMultiwayLeftJoin
extends UnaryExecutableOpBase

TODO: Provide a description of the algorithm implemented by this class.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	ExecOpParallelMultiwayLeftJoin.Worker

Field Summary

Fields

Modifier and Type	Field	Description
protected final Set<List<org.apache.jena.graph.Node>>	bindingsForJoinVariable
protected final List<SolutionMappingsIndex>	indexes
protected final ExpectedVariables	inputVarsFromNonOptionalPart
protected final List<org.apache.jena.sparql.core.Var>	joinVars
protected final List<LogicalOpRequest<?,?>>	optionalParts

Fields inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBase

timeAtCurrentProcStart

Fields inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

collectExceptions

Constructor Summary

Constructors

Constructor	Description
ExecOpParallelMultiwayLeftJoin(boolean collectExceptions, ExpectedVariables inputVarsFromNonOptionalPart, List<LogicalOpRequest<?,?>> optionalParts)
ExecOpParallelMultiwayLeftJoin(boolean collectExceptions, ExpectedVariables inputVarsFromNonOptionalPart, LogicalOpRequest<?,?>... optionalParts)

Method Summary

Modifier and Type	Method	Description
protected void	_concludeExecution(IntermediateResultElementSink sink, ExecutionContext execCxt)	Implementations of this function need to conclude the execution of this operator and send the remaining result elements (if any) to the given sink.
protected void	_process(IntermediateResultBlock input, IntermediateResultElementSink sink, ExecutionContext execCxt)	Implementations of this function need to process the given input block and send the produced result elements (if any) to the given sink.
protected IntermediateResultBlock	determineInputForParallelProcess(IntermediateResultBlock input)	Preprocess the given IntermediateResultBlock to identify the input solution mappings that do not need to be considered during the parallel phase of the algorithm (because they have bindings for the join variables such that there already was an earlier input solution mapping with the same bindings).
protected Set<SolutionMapping>	merge(SolutionMapping inputSol)
protected void	mergePhase(Iterable<SolutionMapping> inputSolMaps, IntermediateResultElementSink sink)
protected void	parallelPhase(IntermediateResultBlock inputForParallelProcess, ExecutionContext execCxt)
int	preferredInputBlockSize()	Returns the preferred block size of input blocks that are passed to this executable operator.

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBase

concludeExecution, createStats, getStats, process, resetStats

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

getExceptionsCaughtDuringExecution, recordExceptionCaughtDuringExecution

Methods inherited from class java.lang.Object

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

Methods inherited from interface se.liu.ida.hefquin.engine.queryplan.executable.ExecutableOperator

getExceptionsCaughtDuringExecution

Field Details

inputVarsFromNonOptionalPart

protected final ExpectedVariables inputVarsFromNonOptionalPart

optionalParts

protected final List<LogicalOpRequest<?,?>> optionalParts

indexes

protected final List<SolutionMappingsIndex> indexes

joinVars

protected final List<org.apache.jena.sparql.core.Var> joinVars

bindingsForJoinVariable

protected final Set<List<org.apache.jena.graph.Node>> bindingsForJoinVariable

Constructor Details

ExecOpParallelMultiwayLeftJoin

public ExecOpParallelMultiwayLeftJoin(boolean collectExceptions,
 ExpectedVariables inputVarsFromNonOptionalPart,
 LogicalOpRequest<?,?>... optionalParts)

ExecOpParallelMultiwayLeftJoin

public ExecOpParallelMultiwayLeftJoin(boolean collectExceptions,
 ExpectedVariables inputVarsFromNonOptionalPart,
 List<LogicalOpRequest<?,?>> optionalParts)

Method Details

preferredInputBlockSize

public int preferredInputBlockSize()

Description copied from interface: UnaryExecutableOp

Returns the preferred block size of input blocks that are passed to this executable operator. A query planner may use this number as an optimization hint but it does not have to use it.

_process

protected void _process(IntermediateResultBlock input,
 IntermediateResultElementSink sink,
 ExecutionContext execCxt)
                 throws ExecOpExecutionException

Description copied from class: UnaryExecutableOpBase

Implementations of this function need to process the given input block and send the produced result elements (if any) to the given sink. If an exception occurs while processing the input block, this exception needs to either be collected or be thrown, depending on whether BaseForExecOps.collectExceptions is set to true.

Specified by:

_process in class UnaryExecutableOpBase

Throws:

ExecOpExecutionException

determineInputForParallelProcess

protected IntermediateResultBlock determineInputForParallelProcess(IntermediateResultBlock input)

Preprocess the given IntermediateResultBlock to identify the input solution mappings that do not need to be considered during the parallel phase of the algorithm (because they have bindings for the join variables such that there already was an earlier input solution mapping with the same bindings). The IntermediateResultBlock returned by this function contains only the solution mappings from the given block that need to be considered.

parallelPhase

protected void parallelPhase(IntermediateResultBlock inputForParallelProcess,
 ExecutionContext execCxt)
                      throws ExecOpExecutionException

Throws:

ExecOpExecutionException

mergePhase

protected void mergePhase(Iterable<SolutionMapping> inputSolMaps,
 IntermediateResultElementSink sink)

merge

protected Set<SolutionMapping> merge(SolutionMapping inputSol)

_concludeExecution

protected void _concludeExecution(IntermediateResultElementSink sink,
 ExecutionContext execCxt)
                           throws ExecOpExecutionException

Description copied from class: UnaryExecutableOpBase

Implementations of this function need to conclude the execution of this operator and send the remaining result elements (if any) to the given sink. If an exception occurs during this process, then this exception needs to either be collected or be thrown, depending on whether BaseForExecOps.collectExceptions is set to true.

Specified by:

_concludeExecution in class UnaryExecutableOpBase

Throws:

ExecOpExecutionException