Package org.apache.calcite.rel.rules

Class ProjectJoinJoinRemoveRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

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

org.apache.calcite.rel.rules.ProjectJoinJoinRemoveRule

All Implemented Interfaces:

SubstitutionRule, TransformationRule

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

Planner rule that matches an Project on a Join and removes the left input of the join provided that the left input is also a left join if possible.

For instance,

select s.product_id, pc.product_id
 from sales as s
 left join product as p
   on s.product_id = p.product_id
 left join product_class pc
   on s.product_id = pc.product_id

becomes

select s.product_id, pc.product_id
 from sales as s
 left join product_class pc
   on s.product_id = pc.product_id

See Also:

• CoreRules.PROJECT_JOIN_JOIN_REMOVE

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ProjectJoinJoinRemoveRule.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
	ProjectJoinJoinRemoveRule(Class<? extends Project> projectClass, Class<? extends Join> joinClass, RelBuilderFactory relBuilderFactory)	Deprecated.
protected	ProjectJoinJoinRemoveRule(ProjectJoinJoinRemoveRule.Config config)	Creates a ProjectJoinJoinRemoveRule.

Method Summary

Modifier and Type	Method	Description
void	onMatch(RelOptRuleCall call)	Receives notification about a rule match.

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

Methods inherited from interface org.apache.calcite.rel.rules.SubstitutionRule

autoPruneOld

Constructor Details

ProjectJoinJoinRemoveRule

protected ProjectJoinJoinRemoveRule(ProjectJoinJoinRemoveRule.Config config)

Creates a ProjectJoinJoinRemoveRule.

ProjectJoinJoinRemoveRule

@Deprecated
public ProjectJoinJoinRemoveRule(Class<? extends Project> projectClass,
 Class<? extends Join> joinClass,
 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)