Class ExecOpHashRJoin

java.lang.Object

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

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

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

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

All Implemented Interfaces:

StatsProvider, BinaryExecutableOp, ExecutableOperator

public class ExecOpHashRJoin
extends ExecOpHashJoin

A right outer join version of the hash join algorithm implemented in ExecOpHashJoin. The only difference is that, when consuming the second input, for every solution mapping that does not have any join partners in the hash index (that was created when consuming the first input), the solution mapping is not simply discarded (as required by the inner join semantics implemented by the base algorithm) but it is sent to the output as is (to comply with the right join semantics).

Attention: if this algorithm is used to implement the OPTIONAL operator, the OPTIONAL part must be used as the first input.

Field Summary

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

child1InputComplete, child2InputComplete, index, statsOfIndex

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

timeAtCurrentLeftProcStart, timeAtCurrentRightProcStart

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

collectExceptions

Constructor Summary

Constructors

Constructor	Description
ExecOpHashRJoin(ExpectedVariables inputVars1, ExpectedVariables inputVars2, boolean collectExceptions)

Method Summary

Modifier and Type	Method	Description
protected void	produceOutput(SolutionMapping inputSolMap, List<SolutionMapping> output)

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

_processInputFromChild1, _processInputFromChild2, _processInputFromChild2, _wrapUpForChild1, _wrapUpForChild2, requiresCompleteChild1InputFirst

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

_processInputFromChild1, createStats, getStats, processInputFromChild1, processInputFromChild1, processInputFromChild2, processInputFromChild2, resetStats, wrapUpForChild1, wrapUpForChild2

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

Constructor Details

ExecOpHashRJoin

public ExecOpHashRJoin(ExpectedVariables inputVars1,
 ExpectedVariables inputVars2,
 boolean collectExceptions)

Method Details

produceOutput

protected void produceOutput(SolutionMapping inputSolMap,
 List<SolutionMapping> output)

Overrides:

produceOutput in class ExecOpHashJoin