org.apache.calcite.rel.rules

Class ValuesReduceRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

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

org.apache.calcite.rel.rules.ValuesReduceRule

All Implemented Interfaces:

TransformationRule

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

Planner rule that folds projections and filters into an underlying LogicalValues.

Returns a simplified Values, perhaps containing zero tuples if all rows are filtered away.

For example,

select a - b from (values (1, 2), (3, 5), (7, 11)) as t (a, b) where a + b > 4

becomes

select x from (values (-2), (-4))

Ignores an empty Values; this is better dealt with by PruneEmptyRules.

See Also:

CoreRules.FILTER_VALUES_MERGE, CoreRules.PROJECT_VALUES_MERGE, CoreRules.PROJECT_FILTER_VALUES_MERGE

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ValuesReduceRule.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 and Description
	ValuesReduceRule(RelOptRuleOperand operand, RelBuilderFactory relBuilderFactory, String desc) Deprecated.
protected	ValuesReduceRule(ValuesReduceRule.Config config) Creates a ValuesReduceRule.

Method Summary

Modifier and Type	Method and Description
protected void	apply(RelOptRuleCall call, @Nullable LogicalProject project, @Nullable LogicalFilter filter, LogicalValues values) Does the work.
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

ValuesReduceRule

protected ValuesReduceRule(ValuesReduceRule.Config config)

Creates a ValuesReduceRule.

ValuesReduceRule

@Deprecated
public ValuesReduceRule(RelOptRuleOperand operand,
                                    RelBuilderFactory relBuilderFactory,
                                    String desc)

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>, org.apache.calcite.plan.RelHintsPropagator) to register the expression.

Specified by:

onMatch in class RelOptRule

Parameters:

call - Rule call

See Also:

RelOptRule.matches(RelOptRuleCall)

apply

protected void apply(RelOptRuleCall call,
                     @Nullable LogicalProject project,
                     @Nullable LogicalFilter filter,
                     LogicalValues values)

Does the work.

Parameters:

call - Rule call

project - Project, may be null

filter - Filter, may be null

values - Values rel to be reduced