Package com.apple.foundationdb.record.query.plan.visitor

Class UnorderedPrimaryKeyDistinctVisitor

java.lang.Object

com.apple.foundationdb.record.query.plan.visitor.RecordQueryPlannerSubstitutionVisitor

com.apple.foundationdb.record.query.plan.visitor.UnorderedPrimaryKeyDistinctVisitor

public class UnorderedPrimaryKeyDistinctVisitor
extends RecordQueryPlannerSubstitutionVisitor

This class moves the index fetch up from the index scan to after a distinct operation has been applied to the records. UnorderedPrimaryKeyDistinct | | RecordQueryPlanWithIndex (Index Lookup) || || V UnorderedPrimaryKeyDistinct (Index Lookup) | | RecordQueryPlanWithIndex (Covering Index)

Field Summary

Fields inherited from class com.apple.foundationdb.record.query.plan.visitor.RecordQueryPlannerSubstitutionVisitor

recordMetadata

Constructor Summary

Constructors

Constructor	Description
UnorderedPrimaryKeyDistinctVisitor(RecordMetaData recordMetadata, PlannableIndexTypes indexTypes, KeyExpression commonPrimaryKey)

Method Summary

Modifier and Type	Method	Description
RecordQueryPlan	postVisit(RecordQueryPlan recordQueryPlan)

Methods inherited from class com.apple.foundationdb.record.query.plan.visitor.RecordQueryPlannerSubstitutionVisitor

applyVisitors, availableFields, availableFields, removeIndexFetch, removeIndexFetch

Methods inherited from class java.lang.Object

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

Constructor Detail

UnorderedPrimaryKeyDistinctVisitor

public UnorderedPrimaryKeyDistinctVisitor(@Nonnull
                                          RecordMetaData recordMetadata,
                                          @Nonnull
                                          PlannableIndexTypes indexTypes,
                                          @Nullable
                                          KeyExpression commonPrimaryKey)

Method Detail

postVisit

@Nonnull
public RecordQueryPlan postVisit(@Nonnull
                                 RecordQueryPlan recordQueryPlan)

Specified by:

postVisit in class RecordQueryPlannerSubstitutionVisitor