public class HTreeDistinctBindingSetsOp extends PipelineOp implements ISingleThreadedOp
HTree
suitable for very large solution sets. Only the variables which are used to
determine the DISTINCT solutions are projected from the operator. The
operator is specific to the RDF data model (it relies on encoded IV
s).
Note: This implementation is a single-threaded pipelined operator which inspects each chunk of solutions as they arrive and those solutions which are distinct for each chunk passed on.
Note: PipelineOp.Annotations#MAX_MEMORY is currently ignored by this
operator. This value could be used to trigger the switch to an external
memory DISTINCT (on a backing store) or to fail a query which attempts to put
too much data into the native heap. Right now, it will just keep adding data
on the native heap and eventually the machine will begin to swap.
| Modifier and Type | Class and Description |
|---|---|
static interface |
HTreeDistinctBindingSetsOp.Annotations |
DEFAULT_INITIAL_CAPACITY| Constructor and Description |
|---|
HTreeDistinctBindingSetsOp(BOp[] args,
Map<String,Object> annotations)
Required shallow copy constructor.
|
HTreeDistinctBindingSetsOp(BOp[] args,
NV... annotations) |
HTreeDistinctBindingSetsOp(HTreeDistinctBindingSetsOp op)
Constructor required for
com.bigdata.bop.BOpUtility#deepCopy(FilterNode). |
| Modifier and Type | Method and Description |
|---|---|
FutureTask<Void> |
eval(BOpContext<IBindingSet> context)
Return a
FutureTask which computes the operator against the
evaluation context. |
assertAtOnceJavaHeapOp, assertMaxParallelOne, getChunkCapacity, getChunkOfChunksCapacity, getChunkTimeout, getMaxMemory, getMaxParallel, isAtOnceEvaluation, isBlockedEvaluation, isLastPassRequested, isPipelinedEvaluation, isReorderSolutions, isSharedState, newStats__replaceArg, _clearProperty, _set, _setProperty, annotations, annotationsCopy, annotationsEqual, annotationsRef, argIterator, args, argsCopy, arity, clearAnnotations, clearProperty, deepCopy, deepCopy, get, getProperty, setArg, setProperty, setUnboundProperty, toArray, toArrayannotationsEqual, annotationsToString, annotationsToString, annotationValueToString, checkArgs, clone, equals, getEvaluationContext, getId, getProperty, getRequiredProperty, hashCode, indent, isController, mutation, shortenName, toShortString, toString, toStringpublic HTreeDistinctBindingSetsOp(HTreeDistinctBindingSetsOp op)
com.bigdata.bop.BOpUtility#deepCopy(FilterNode).public HTreeDistinctBindingSetsOp(BOp[] args, Map<String,Object> annotations)
public FutureTask<Void> eval(BOpContext<IBindingSet> context)
PipelineOpFutureTask 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).eval in class PipelineOpcontext - The evaluation context.FutureTask which will compute the operator's
evaluation.Copyright © 2006–2019 SYSTAP, LLC DBA Blazegraph. All rights reserved.