Package com.apple.foundationdb.record.query.plan.temp.expressions

Class LogicalIntersectionExpression

java.lang.Object

com.apple.foundationdb.record.query.plan.temp.expressions.LogicalIntersectionExpression

All Implemented Interfaces:

Bindable, Correlated<RelationalExpression>, InternalPlannerGraphRewritable, RelationalExpressionWithChildren, RelationalExpression

@API(INTERNAL)
public class LogicalIntersectionExpression
extends Object
implements RelationalExpressionWithChildren, InternalPlannerGraphRewritable

A query plan that executes by taking the union of records from two or more compatibly-sorted child plans. To work, each child cursor must order its children the same way according to the comparison key.

Nested Class Summary

Nested classes/interfaces inherited from interface com.apple.foundationdb.record.query.plan.temp.Correlated

Correlated.BoundEquivalence

Nested classes/interfaces inherited from interface com.apple.foundationdb.record.query.plan.temp.RelationalExpression

RelationalExpression.CombineFunction<R,S>, RelationalExpression.CombinePredicate

Field Summary

Fields

Modifier and Type	Field	Description
static org.slf4j.Logger	LOGGER

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object other)
boolean	equalsWithoutChildren(RelationalExpression otherExpression, AliasMap equivalencesMap)
static LogicalIntersectionExpression	from(List<RelationalExpression> children, KeyExpression comparisonKey)	Construct a new union of two or more compatibly-ordered plans.
KeyExpression	getComparisonKey()
Set<CorrelationIdentifier>	getCorrelatedToWithoutChildren()
List<? extends Quantifier>	getQuantifiers()	Return an iterator of references to the children of this planner expression.
int	getRelationalChildCount()
int	hashCode()
int	hashCodeWithoutChildren()
LogicalIntersectionExpression	rebaseWithRebasedQuantifiers(AliasMap translationMap, List<Quantifier> rebasedQuantifiers)
PlannerGraph	rewriteInternalPlannerGraph(List<? extends PlannerGraph> childGraphs)	Method to rewrite the planner graph.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.apple.foundationdb.record.query.plan.temp.RelationalExpression

acceptPropertyVisitor, adjustMatch, bindIdentities, bindTo, canCorrelate, compensate, enumerateUnboundCorrelatedTo, exactlySubsumedBy, findMatches, getResultValues, hasIncompatibleBoundQuantifiers, hasUnboundQuantifiers, match, match, semanticEquals, semanticEquals, semanticHashCode, show, subsumedBy

Methods inherited from interface com.apple.foundationdb.record.query.plan.temp.expressions.RelationalExpressionWithChildren

getCorrelatedTo, rebase

Field Detail

LOGGER

public static final org.slf4j.Logger LOGGER

Method Detail

getComparisonKey

@Nonnull
public KeyExpression getComparisonKey()

getQuantifiers

@Nonnull
public List<? extends Quantifier> getQuantifiers()

Description copied from interface: RelationalExpression

Return an iterator of references to the children of this planner expression. The iterators returned by different calls are guaranteed to be independent (i.e., advancing one will not advance another). However, they might point to the same object, as when Collections.emptyIterator() is returned. The returned iterator should be treated as an immutable object and may throw an exception if Iterator.remove() is called. The iterator must return its elements in a consistent order.

Specified by:

getQuantifiers in interface RelationalExpression

Returns:

an iterator of references to the children of this planner expression

toString

@Nonnull
public String toString()

Overrides:

toString in class Object

getCorrelatedToWithoutChildren

@Nonnull
public Set<CorrelationIdentifier> getCorrelatedToWithoutChildren()

Specified by:

getCorrelatedToWithoutChildren in interface RelationalExpressionWithChildren

rebaseWithRebasedQuantifiers

@Nonnull
public LogicalIntersectionExpression rebaseWithRebasedQuantifiers(@Nonnull
                                                                  AliasMap translationMap,
                                                                  @Nonnull
                                                                  List<Quantifier> rebasedQuantifiers)

Specified by:

rebaseWithRebasedQuantifiers in interface RelationalExpressionWithChildren

equalsWithoutChildren

public boolean equalsWithoutChildren(@Nonnull
                                     RelationalExpression otherExpression,
                                     @Nonnull
                                     AliasMap equivalencesMap)

Specified by:

equalsWithoutChildren in interface RelationalExpression

equals

public boolean equals(Object other)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

hashCodeWithoutChildren

public int hashCodeWithoutChildren()

Specified by:

hashCodeWithoutChildren in interface RelationalExpression

getRelationalChildCount

public int getRelationalChildCount()

Specified by:

getRelationalChildCount in interface RelationalExpressionWithChildren

from

@Nonnull
public static LogicalIntersectionExpression from(@Nonnull
                                                 List<RelationalExpression> children,
                                                 @Nonnull
                                                 KeyExpression comparisonKey)

Construct a new union of two or more compatibly-ordered plans. The resulting plan will return all results that are returned by all of the child plans. Each plan should return results in the same order according to the provided comparisonKey.

Parameters:

children - the list of plans to take the intersection of

comparisonKey - a key expression by which the results of both plans are ordered

Returns:

a new plan that will return the intersection of all results from both child plans

rewriteInternalPlannerGraph

@Nonnull
public PlannerGraph rewriteInternalPlannerGraph(@Nonnull
                                                List<? extends PlannerGraph> childGraphs)

Description copied from interface: InternalPlannerGraphRewritable

Method to rewrite the planner graph.

Specified by:

rewriteInternalPlannerGraph in interface InternalPlannerGraphRewritable

Parameters:

childGraphs - planner graphs of children expression that already have been computed

Returns:

a new planner graph that can combine the childGraphs in a meaningful way. Note that there is no obligation to use the childGraphs at all, this method can create a new independent planner graph completely from scratch.