Package org.apache.calcite.rel.rules

Class ProjectRemoveRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

org.apache.calcite.plan.RelRule<ProjectRemoveRule.Config>

org.apache.calcite.rel.rules.ProjectRemoveRule

All Implemented Interfaces:

SubstitutionRule, TransformationRule

@Enclosing
public class ProjectRemoveRule
extends RelRule<ProjectRemoveRule.Config>
implements SubstitutionRule

Planner rule that, given a Project node that merely returns its input, converts the node into its child.

For example, Project(ArrayReader(a), {$input0}) becomes ArrayReader(a).

See Also:

• CalcRemoveRule
• ProjectMergeRule
• CoreRules.PROJECT_REMOVE

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ProjectRemoveRule.Config	Rule configuration.

Nested classes/interfaces inherited from class org.apache.calcite.plan.RelRule

RelRule.Done, RelRule.MatchHandler<R extends RelOptRule>, RelRule.OperandBuilder, RelRule.OperandDetailBuilder<R extends RelNode>, RelRule.OperandTransform

Nested classes/interfaces inherited from class org.apache.calcite.plan.RelOptRule

RelOptRule.ConverterRelOptRuleOperand

Field Summary

Fields inherited from class org.apache.calcite.plan.RelRule

config

Fields inherited from class org.apache.calcite.plan.RelOptRule

description, operands, relBuilderFactory

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ProjectRemoveRule(ProjectRemoveRule.Config config)	Creates a ProjectRemoveRule.
	ProjectRemoveRule(RelBuilderFactory relBuilderFactory)	Deprecated.

Method Summary

Modifier and Type	Method	Description
boolean	autoPruneOld()	Whether the planner should automatically prune old node when there is at least 1 equivalent rel generated by the rule.
static boolean	isTrivial(Project project)
void	onMatch(RelOptRuleCall call)	Receives notification about a rule match.
static RelNode	strip(Project project)	Returns the child of a project if the project is trivial, otherwise the project itself.

Methods inherited from class org.apache.calcite.plan.RelOptRule

any, convert, convert, convert, convert, convertList, convertOperand, convertOperand, equals, equals, getOperand, getOperands, getOutConvention, getOutTrait, hashCode, matches, none, operand, operand, operand, operand, operand, operandJ, operandJ, some, toString, unordered

Methods inherited from class java.lang.Object

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

Constructor Details

ProjectRemoveRule

protected ProjectRemoveRule(ProjectRemoveRule.Config config)

Creates a ProjectRemoveRule.

ProjectRemoveRule

@Deprecated
public ProjectRemoveRule(RelBuilderFactory relBuilderFactory)

Deprecated.

Method Details

onMatch

public void onMatch(RelOptRuleCall call)

Description copied from class: RelOptRule

Receives notification about a rule match. At the time that this method is called, call.rels holds the set of relational expressions which match the operands to the rule; call.rels[0] is the root expression.

Typically a rule would check that the nodes are valid matches, creates a new expression, then calls back RelOptRuleCall.transformTo(org.apache.calcite.rel.RelNode, java.util.Map<org.apache.calcite.rel.RelNode, org.apache.calcite.rel.RelNode>, org.apache.calcite.plan.RelHintsPropagator) to register the expression.

Specified by:

onMatch in class RelOptRule

Parameters:

call - Rule call

See Also:

• RelOptRule.matches(RelOptRuleCall)

strip

public static RelNode strip(Project project)

Returns the child of a project if the project is trivial, otherwise the project itself.

isTrivial

public static boolean isTrivial(Project project)

autoPruneOld

public boolean autoPruneOld()

Description copied from interface: SubstitutionRule

Whether the planner should automatically prune old node when there is at least 1 equivalent rel generated by the rule.

Default is false, the user needs to prune the old node manually in the rule.

Specified by:

autoPruneOld in interface SubstitutionRule