org.apache.calcite.sql2rel

Class RelDecorrelator.CorelMap

java.lang.Object

org.apache.calcite.sql2rel.RelDecorrelator.CorelMap

Enclosing class:

RelDecorrelator

protected static class RelDecorrelator.CorelMap
extends Object

A map of the locations of Correlate in a tree of RelNodes.

It is used to drive the decorrelation process. Treat it as immutable; rebuild if you modify the tree.

There are three maps:

1. mapRefRelToCorRef maps a RelNode to the correlated variables it references;
2. mapCorToCorRel maps a correlated variable to the Correlate providing it;
3. mapFieldAccessToCorRef maps a rex field access to the corVar it represents. Because typeFlattener does not clone or modify a correlated field access this map does not need to be updated.

Method Summary

Modifier and Type	Method and Description
boolean	equals(@Nullable Object obj)
NavigableMap<CorrelationId,RelNode>	getMapCorToCorRel()
boolean	hasCorrelation() Returns whether there are any correlating variables in this statement.
int	hashCode()
static RelDecorrelator.CorelMap	of(com.google.common.collect.SortedSetMultimap<RelNode,org.apache.calcite.sql2rel.RelDecorrelator.CorRef> mapRefRelToCorVar, NavigableMap<CorrelationId,RelNode> mapCorToCorRel, Map<RexFieldAccess,org.apache.calcite.sql2rel.RelDecorrelator.CorRef> mapFieldAccessToCorVar) Creates a CorelMap with given contents.
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(@Nullable Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

of

public static RelDecorrelator.CorelMap of(com.google.common.collect.SortedSetMultimap<RelNode,org.apache.calcite.sql2rel.RelDecorrelator.CorRef> mapRefRelToCorVar,
                                          NavigableMap<CorrelationId,RelNode> mapCorToCorRel,
                                          Map<RexFieldAccess,org.apache.calcite.sql2rel.RelDecorrelator.CorRef> mapFieldAccessToCorVar)

Creates a CorelMap with given contents.

getMapCorToCorRel

public NavigableMap<CorrelationId,RelNode> getMapCorToCorRel()

hasCorrelation

public boolean hasCorrelation()

Returns whether there are any correlating variables in this statement.

Returns:

whether there are any correlating variables