org.openrdf.query.algebra.evaluation.impl
Class QueryJoinOptimizer.JoinVisitor

java.lang.Object
  org.openrdf.query.algebra.helpers.QueryModelVisitorBase<RuntimeException>
      org.openrdf.query.algebra.evaluation.impl.QueryJoinOptimizer.JoinVisitor

All Implemented Interfaces:

QueryModelVisitor<RuntimeException>

Enclosing class:

QueryJoinOptimizer

protected class QueryJoinOptimizer.JoinVisitor
extends QueryModelVisitorBase<RuntimeException>

Constructor Summary

protected

QueryJoinOptimizer.JoinVisitor()

Method Summary

protected List<Var>	getConstantVars(Iterable<Var> vars)
protected int	getForeignVarFreq(List<Var> ownUnboundVars, Map<Var,Integer> varFreqMap)
protected <L extends List<TupleExpr>> L	getJoinArgs(TupleExpr tupleExpr, L joinArgs)
protected List<Var>	getStatementPatternVars(TupleExpr tupleExpr)
protected double	getTupleExprCardinality(TupleExpr tupleExpr, Map<TupleExpr,Double> cardinalityMap, Map<TupleExpr,List<Var>> varsMap, Map<Var,Integer> varFreqMap, Set<String> boundVars)
protected List<Var>	getUnboundVars(Iterable<Var> vars)
protected <M extends Map<Var,Integer>> M	getVarFreqMap(List<Var> varList, M varFreqMap)
void	meet(Join node)
void	meet(LeftJoin leftJoin)
protected TupleExpr	selectNextTupleExpr(List<TupleExpr> expressions, Map<TupleExpr,Double> cardinalityMap, Map<TupleExpr,List<Var>> varsMap, Map<Var,Integer> varFreqMap, Set<String> boundVars) Selects from a list of tuple expressions the next tuple expression that should be evaluated.

Methods inherited from class org.openrdf.query.algebra.helpers.QueryModelVisitorBase

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, meetNode, meetOther, meetSubQueryValueOperator, meetUnaryTupleOperator, meetUnaryValueOperator

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryJoinOptimizer.JoinVisitor

protected QueryJoinOptimizer.JoinVisitor()

Method Detail

meet

public void meet(LeftJoin leftJoin)

Specified by:

meet in interface QueryModelVisitor<RuntimeException>

Overrides:

meet in class QueryModelVisitorBase<RuntimeException>

meet

public void meet(Join node)

Specified by:

meet in interface QueryModelVisitor<RuntimeException>

Overrides:

meet in class QueryModelVisitorBase<RuntimeException>

getJoinArgs

protected <L extends List<TupleExpr>> L getJoinArgs(TupleExpr tupleExpr,
                                                    L joinArgs)

getStatementPatternVars

protected List<Var> getStatementPatternVars(TupleExpr tupleExpr)

getVarFreqMap

protected <M extends Map<Var,Integer>> M getVarFreqMap(List<Var> varList,
                                                       M varFreqMap)

selectNextTupleExpr

protected TupleExpr selectNextTupleExpr(List<TupleExpr> expressions,
                                        Map<TupleExpr,Double> cardinalityMap,
                                        Map<TupleExpr,List<Var>> varsMap,
                                        Map<Var,Integer> varFreqMap,
                                        Set<String> boundVars)

Selects from a list of tuple expressions the next tuple expression that should be evaluated. This method selects the tuple expression with highest number of bound variables, preferring variables that have been bound in other tuple expressions over variables with a fixed value.

getTupleExprCardinality

protected double getTupleExprCardinality(TupleExpr tupleExpr,
                                         Map<TupleExpr,Double> cardinalityMap,
                                         Map<TupleExpr,List<Var>> varsMap,
                                         Map<Var,Integer> varFreqMap,
                                         Set<String> boundVars)

getConstantVars

protected List<Var> getConstantVars(Iterable<Var> vars)

getUnboundVars

protected List<Var> getUnboundVars(Iterable<Var> vars)

getForeignVarFreq

protected int getForeignVarFreq(List<Var> ownUnboundVars,
                                Map<Var,Integer> varFreqMap)