Package org.apache.calcite.rel.rules

Class SemiJoinRemoveRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

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

org.apache.calcite.rel.rules.SemiJoinRemoveRule

All Implemented Interfaces:

TransformationRule

@Enclosing
public class SemiJoinRemoveRule
extends RelRule<SemiJoinRemoveRule.Config>
implements TransformationRule

Planner rule that removes a semi-join from a join tree.

It is invoked after attempts have been made to convert a SemiJoin to an indexed scan on a join factor have failed. Namely, if the join factor does not reduce to a single table that can be scanned using an index.

It should only be enabled if all SemiJoins in the plan are advisory; that is, they can be safely dropped without affecting the semantics of the query.

See Also:

• CoreRules.SEMI_JOIN_REMOVE

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	SemiJoinRemoveRule.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	SemiJoinRemoveRule(SemiJoinRemoveRule.Config config)	Creates a SemiJoinRemoveRule.
	SemiJoinRemoveRule(RelBuilderFactory relBuilderFactory)	Deprecated.

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

Constructor Details

SemiJoinRemoveRule

protected SemiJoinRemoveRule(SemiJoinRemoveRule.Config config)

Creates a SemiJoinRemoveRule.

SemiJoinRemoveRule

@Deprecated
public SemiJoinRemoveRule(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)