com.bigdata.bop.join

Class FastRangeCountOp<E>

java.lang.Object

com.bigdata.bop.CoreBaseBOp

com.bigdata.bop.BOpBase

com.bigdata.bop.PipelineOp

com.bigdata.bop.join.FastRangeCountOp<E>

All Implemented Interfaces:

BOp, IPropertySet, Serializable, Cloneable

public class FastRangeCountOp<E>
extends PipelineOp

This operator reports the fast-range count for an as-bound IPredicate . The cost of this operator is two key probes. Unlike a normal access path, this operator does not bind variables to data in tuples in the underlying index. Instead it binds a pre-identified variable to the aggregate (COUNT) of the tuple range spanned by the IPredicate.

Author:

Bryan Thompson

See Also:

Rewrite SELECT COUNT(...) (DISTINCT|REDUCED) {single-triple-pattern} as ESTCARD , Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	FastRangeCountOp.Annotations
protected static class	FastRangeCountOp.ChunkTask<E> Copy the source to the sink.

Field Summary

Fields inherited from class com.bigdata.bop.CoreBaseBOp

DEFAULT_INITIAL_CAPACITY

Fields inherited from interface com.bigdata.bop.BOp

NOANNS, NOARGS

Constructor Summary

Constructors

Constructor and Description
FastRangeCountOp(BOp[] args, Map<String,Object> annotations) Shallow copy constructor.
FastRangeCountOp(BOp[] args, NV... annotations)
FastRangeCountOp(FastRangeCountOp<E> op) Deep copy constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected IConstraint[]	constraints()
FutureTask<Void>	eval(BOpContext<IBindingSet> context) Return a FutureTask which computes the operator against the evaluation context.
protected IVariable<?>	getCountVar()
IPredicate<E>	getPredicate()
protected IVariable<?>[]	getSelect()

Methods inherited from class com.bigdata.bop.PipelineOp

assertAtOnceJavaHeapOp, assertMaxParallelOne, getChunkCapacity, getChunkOfChunksCapacity, getChunkTimeout, getMaxMemory, getMaxParallel, isAtOnceEvaluation, isBlockedEvaluation, isLastPassRequested, isPipelinedEvaluation, isReorderSolutions, isSharedState, newStats

Methods inherited from class com.bigdata.bop.BOpBase

__replaceArg, _clearProperty, _set, _setProperty, annotations, annotationsCopy, annotationsEqual, annotationsRef, argIterator, args, argsCopy, arity, clearAnnotations, clearProperty, deepCopy, deepCopy, get, getProperty, setArg, setProperty, setUnboundProperty, toArray, toArray

Methods inherited from class com.bigdata.bop.CoreBaseBOp

annotationsEqual, annotationsToString, annotationsToString, annotationValueToString, checkArgs, clone, equals, getEvaluationContext, getId, getProperty, getRequiredProperty, hashCode, indent, isController, mutation, shortenName, toShortString, toString, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

FastRangeCountOp

public FastRangeCountOp(FastRangeCountOp<E> op)

Deep copy constructor.

Parameters:

op -

FastRangeCountOp

public FastRangeCountOp(BOp[] args,
                Map<String,Object> annotations)

Shallow copy constructor.

Parameters:

args -

annotations -

FastRangeCountOp

public FastRangeCountOp(BOp[] args,
                NV... annotations)

Method Detail

getCountVar

protected IVariable<?> getCountVar()

See Also:

FastRangeCountOp.Annotations.COUNT_VAR

getSelect

protected IVariable<?>[] getSelect()

See Also:

JoinAnnotations.SELECT

constraints

protected IConstraint[] constraints()

See Also:

JoinAnnotations.CONSTRAINTS

getPredicate

public IPredicate<E> getPredicate()

eval

public FutureTask<Void> eval(BOpContext<IBindingSet> context)

Description copied from class: PipelineOp

Return a FutureTask which computes the operator against the evaluation context. The caller is responsible for executing the FutureTask (this gives them the ability to hook the completion of the computation).

Specified by:

eval in class PipelineOp

Parameters:

context - The evaluation context.

Returns:

The FutureTask which will compute the operator's evaluation.