com.bigdata.rdf.sail
Class BigdataEvaluationStatistics

java.lang.Object
  org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics
      com.bigdata.rdf.sail.BigdataEvaluationStatistics

public class BigdataEvaluationStatistics
extends org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics

Uses range counts to give cost estimates based on the size of the expected results. Note that this class is NOT used when BigdataSail.Options.NATIVE_JOINS is enabled since the IRule execution will automatically assign its own evaluation plan and that evaluation plan will be informed by the range counts. See BigdataSail.BigdataSailConnection.evaluate(TupleExpr, Dataset, BindingSet, boolean) FIXME quads : if a StatementPattern is to read against the default context and that is a merge of pre-defined contexts then we need to use the union of the range counts for those contexts.

Nested Class Summary

protected class

BigdataEvaluationStatistics.BigdataCardinalityCalculator These uses range counts on the various StatementPatterns to influence the cardinality.

Nested classes/interfaces inherited from class org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics

org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics.CardinalityCalculator

Field Summary

protected static org.apache.log4j.Logger

log Logger.

Fields inherited from class org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics

cc

Constructor Summary

BigdataEvaluationStatistics(BigdataSail.BigdataSailConnection conn)

Method Summary

protected org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics.CardinalityCalculator

createCardinalityCalculator()

Methods inherited from class org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics

getCardinality

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.apache.log4j.Logger log

Logger.

Constructor Detail

BigdataEvaluationStatistics

public BigdataEvaluationStatistics(BigdataSail.BigdataSailConnection conn)

Method Detail

createCardinalityCalculator

protected org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics.CardinalityCalculator createCardinalityCalculator()

Overrides:

createCardinalityCalculator in class org.openrdf.query.algebra.evaluation.impl.EvaluationStatistics