Package org.apache.calcite.rel.rules

Class PruneEmptyRules.RemoveEmptySingleRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

org.apache.calcite.rel.rules.PruneEmptyRules.RemoveEmptySingleRule

Enclosing class:

PruneEmptyRules

public static class PruneEmptyRules.RemoveEmptySingleRule
extends RelOptRule

Planner rule that converts a single-rel (e.g. project, sort, aggregate or filter) on top of the empty relational expression into empty.

Field Summary

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

description, operands, relBuilderFactory

Constructor Summary

Constructors

Constructor	Description
RemoveEmptySingleRule(java.lang.Class<R> clazz, com.google.common.base.Predicate<R> predicate, RelBuilderFactory relBuilderFactory, java.lang.String description)	Deprecated.
RemoveEmptySingleRule(java.lang.Class<R> clazz, java.lang.String description)	Creates a simple RemoveEmptySingleRule.
RemoveEmptySingleRule(java.lang.Class<R> clazz, java.util.function.Predicate<R> predicate, RelBuilderFactory relBuilderFactory, java.lang.String description)	Creates a RemoveEmptySingleRule.

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, 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 Detail

RemoveEmptySingleRule

public RemoveEmptySingleRule(java.lang.Class<R> clazz,
                             java.lang.String description)

Creates a simple RemoveEmptySingleRule.

RemoveEmptySingleRule

public RemoveEmptySingleRule(java.lang.Class<R> clazz,
                             java.util.function.Predicate<R> predicate,
                             RelBuilderFactory relBuilderFactory,
                             java.lang.String description)

Creates a RemoveEmptySingleRule.

RemoveEmptySingleRule

@Deprecated
public RemoveEmptySingleRule(java.lang.Class<R> clazz,
                             com.google.common.base.Predicate<R> predicate,
                             RelBuilderFactory relBuilderFactory,
                             java.lang.String description)

Deprecated.

Method Detail

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>) to register the expression.

Specified by:

onMatch in class RelOptRule

Parameters:

call - Rule call

See Also:

RelOptRule.matches(RelOptRuleCall)