net.sf.saffron.rel
Class JoinRel

java.lang.Object
  |
  +--net.sf.saffron.rel.SaffronRel
        |
        +--net.sf.saffron.rel.JoinRel

Direct Known Subclasses:

CorrelatorRel, JavaNestedLoopJoinRel

public class JoinRel

extends SaffronRel

A JoinRel represents two relational expressions joined according to some condition.

Nested Class Summary

static class

JoinRel.JoinType Enumeration of join types.

Field Summary

protected RexNode	condition
protected int	joinType Values must be of enumeration JoinRel.JoinType, except that JoinRel.JoinType.RIGHT is disallowed.
protected SaffronRel	left
protected SaffronRel	right
protected Set	variablesStopped

Fields inherited from class net.sf.saffron.rel.SaffronRel

cluster, digest, emptyArray, id, nextId, rowType

Constructor Summary

JoinRel(VolcanoCluster cluster, SaffronRel left, SaffronRel right, RexNode condition, int joinType, Set variablesStopped)

Method Summary

private static void	addFields(SaffronType type, ArrayList typeList, ArrayList nameList)
void	childrenAccept(RelVisitor visitor)
Object	clone()
private SaffronType	createJoinType(SaffronType leftType, SaffronType rightType)
protected SaffronType	deriveRowType()
void	explain(PlanWriter pw)
RexNode[]	getChildExps() Returns an array of this SaffronRel's child expressions (not including the inputs returned by getInputs().
RexNode	getCondition()
SaffronRel[]	getInputs() Returns an array of this SaffronRel's inputs.
int	getJoinType()
SaffronRel	getLeft()
SaffronRel	getRight()
Set	getVariablesStopped() Returns the names of variables which are set in this relational expression but also used and therefore not available to parents of this relational expression.
void	registerStoppedVariable(String name)
void	replaceInput(int ordinalInParent, SaffronRel p) Replaces the ordinalInParentth input.
void	setVariablesStopped(HashSet set)
int	switchJoinType(int joinType)

Methods inherited from class net.sf.saffron.rel.SaffronRel

computeDigest, computeSelfCost, getCluster, getConvention, getCorrelVariable, getId, getInput, getOrCreateCorrelVariable, getQualifier, getQuery, getRelTypeName, getRows, getRowType, getTable, implement, implementFieldAccess, isAccessTo, isDistinct, onRegister, recomputeDigest, register, registerCorrelVariable, setCorrelVariable, toString

Methods inherited from class java.lang.Object

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

Field Detail

condition

protected RexNode condition

left

protected SaffronRel left

right

protected SaffronRel right

variablesStopped

protected Set variablesStopped

joinType

protected int joinType

Values must be of enumeration JoinRel.JoinType, except that JoinRel.JoinType.RIGHT is disallowed.

Constructor Detail

JoinRel

public JoinRel(VolcanoCluster cluster,
               SaffronRel left,
               SaffronRel right,
               RexNode condition,
               int joinType,
               Set variablesStopped)

Method Detail

getChildExps

public RexNode[] getChildExps()

Description copied from class: SaffronRel

Returns an array of this SaffronRel's child expressions (not including the inputs returned by SaffronRel.getInputs(). If there are no child expressions, returns an empty array, not null.

Overrides:

getChildExps in class SaffronRel

getCondition

public RexNode getCondition()

getInputs

public SaffronRel[] getInputs()

Description copied from class: SaffronRel

Returns an array of this SaffronRel's inputs. If there are no inputs, returns an empty array, not null.

Overrides:

getInputs in class SaffronRel

getJoinType

public int getJoinType()

getLeft

public SaffronRel getLeft()

getRight

public SaffronRel getRight()

setVariablesStopped

public void setVariablesStopped(HashSet set)

getVariablesStopped

public Set getVariablesStopped()

Description copied from class: SaffronRel

Returns the names of variables which are set in this relational expression but also used and therefore not available to parents of this relational expression.

By default, returns the empty set. Derived classes may override this method.

Overrides:

getVariablesStopped in class SaffronRel

childrenAccept

public void childrenAccept(RelVisitor visitor)

Overrides:

childrenAccept in class SaffronRel

clone

public Object clone()

Specified by:

clone in class SaffronRel

explain

public void explain(PlanWriter pw)

Overrides:

explain in class SaffronRel

registerStoppedVariable

public void registerStoppedVariable(String name)

replaceInput

public void replaceInput(int ordinalInParent,
                         SaffronRel p)

Description copied from class: SaffronRel

Replaces the ordinalInParent^th input. You must override this method if you override SaffronRel.getInputs().

Overrides:

replaceInput in class SaffronRel

switchJoinType

public int switchJoinType(int joinType)

deriveRowType

protected SaffronType deriveRowType()

Specified by:

deriveRowType in class SaffronRel

createJoinType

private SaffronType createJoinType(SaffronType leftType,
                                   SaffronType rightType)

addFields

private static void addFields(SaffronType type,
                              ArrayList typeList,
                              ArrayList nameList)