org.apache.calcite.sql2rel

Class DeduplicateCorrelateVariables

java.lang.Object

org.apache.calcite.rel.RelShuttleImpl

org.apache.calcite.rel.RelHomogeneousShuttle

org.apache.calcite.sql2rel.DeduplicateCorrelateVariables

All Implemented Interfaces:

RelShuttle

public class DeduplicateCorrelateVariables
extends RelHomogeneousShuttle

Rewrites relations to ensure the same correlation is referenced by the same correlation variable.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	DeduplicateCorrelateVariables.DeduplicateCorrelateVariablesShuttle Replaces alternative names of correlation variable to its canonical name.

Field Summary

Fields

Modifier and Type	Field and Description
private RexShuttle	dedupRex

Fields inherited from class org.apache.calcite.rel.RelShuttleImpl

stack

Constructor Summary

Constructors

Modifier	Constructor and Description
private	DeduplicateCorrelateVariables(RexBuilder builder, CorrelationId canonicalId, com.google.common.collect.ImmutableSet<CorrelationId> alternateIds) Creates a DeduplicateCorrelateVariables.

Method Summary

Modifier and Type	Method and Description
static RelNode	go(RexBuilder builder, CorrelationId canonicalId, Iterable<? extends CorrelationId> alternateIds, RelNode r) Rewrites a relational expression, replacing alternate correlation variables with a canonical correlation variable.
RelNode	visit(RelNode other)

Methods inherited from class org.apache.calcite.rel.RelHomogeneousShuttle

visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class org.apache.calcite.rel.RelShuttleImpl

visitChild, visitChildren

Methods inherited from class java.lang.Object

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

Field Detail

dedupRex

private final RexShuttle dedupRex

Constructor Detail

DeduplicateCorrelateVariables

private DeduplicateCorrelateVariables(RexBuilder builder,
                                      CorrelationId canonicalId,
                                      com.google.common.collect.ImmutableSet<CorrelationId> alternateIds)

Creates a DeduplicateCorrelateVariables.

Method Detail

go

public static RelNode go(RexBuilder builder,
                         CorrelationId canonicalId,
                         Iterable<? extends CorrelationId> alternateIds,
                         RelNode r)

Rewrites a relational expression, replacing alternate correlation variables with a canonical correlation variable.

visit

public RelNode visit(RelNode other)

Specified by:

visit in interface RelShuttle

Overrides:

visit in class RelShuttleImpl