vishnu.model.algebra.optimizer
Class ProjectionForwardingTranslationStage

java.lang.Object
  vishnu.model.algebra.optimizer.AbstractTranslationStage
      vishnu.model.algebra.optimizer.ChildVisitorTranslationStage
          vishnu.model.algebra.optimizer.ProjectionForwardingTranslationStage

All Implemented Interfaces:

TranslationStage, VisitorTranslationStage

public class ProjectionForwardingTranslationStage
extends ChildVisitorTranslationStage

Author:

Hernan Rancati

Constructor Summary

ProjectionForwardingTranslationStage()

Method Summary

protected java.util.List<java.lang.String>	requiredColumns(java.util.Collection<java.lang.String> columns, Relation r, Database d)
Relation	visit(Relation r, UserContext uc)

Methods inherited from class vishnu.model.algebra.optimizer.ChildVisitorTranslationStage

perform

Methods inherited from class vishnu.model.algebra.optimizer.AbstractTranslationStage

attach

Methods inherited from class java.lang.Object

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

Constructor Detail

ProjectionForwardingTranslationStage

public ProjectionForwardingTranslationStage()

Method Detail

visit

public Relation visit(Relation r,
                      UserContext uc)

Specified by:

visit in interface VisitorTranslationStage

Specified by:

visit in class ChildVisitorTranslationStage

requiredColumns

protected java.util.List<java.lang.String> requiredColumns(java.util.Collection<java.lang.String> columns,
                                                           Relation r,
                                                           Database d)