io.prestosql.sql.planner.iterative.rule

Class ProjectOffPushDownRule<N extends PlanNode>

java.lang.Object

io.prestosql.sql.planner.iterative.rule.ProjectOffPushDownRule<N>

Type Parameters:

N - The node type to look for under the ProjectNode Looks for a Project parent over a N child, such that the parent doesn't use all the output columns of the child. Given that situation, invokes the pushDownProjectOff helper to possibly rewrite the child to produce fewer outputs.

All Implemented Interfaces:

Rule<ProjectNode>

Direct Known Subclasses:

PruneAggregationColumns, PruneCrossJoinColumns, PruneFilterColumns, PruneIndexSourceColumns, PruneJoinColumns, PruneLimitColumns, PruneMarkDistinctColumns, PruneProjectColumns, PruneSemiJoinColumns, PruneTableScanColumns, PruneTopNColumns, PruneValuesColumns, PruneWindowColumns

public abstract class ProjectOffPushDownRule<N extends PlanNode>
extends Object
implements Rule<ProjectNode>

Nested Class Summary

Nested classes/interfaces inherited from interface io.prestosql.sql.planner.iterative.Rule

Rule.Context, Rule.Result

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ProjectOffPushDownRule(Pattern<N> targetPattern)

Method Summary

Modifier and Type	Method and Description
Rule.Result	apply(ProjectNode parent, Captures captures, Rule.Context context)
Pattern<ProjectNode>	getPattern() Returns a pattern to which plan nodes this rule applies.
protected abstract Optional<PlanNode>	pushDownProjectOff(PlanNodeIdAllocator idAllocator, N targetNode, Set<Symbol> referencedOutputs)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface io.prestosql.sql.planner.iterative.Rule

isEnabled

Constructor Detail

ProjectOffPushDownRule

protected ProjectOffPushDownRule(Pattern<N> targetPattern)

Method Detail

getPattern

public Pattern<ProjectNode> getPattern()

Description copied from interface: Rule

Returns a pattern to which plan nodes this rule applies.

Specified by:

getPattern in interface Rule<ProjectNode>

apply

public Rule.Result apply(ProjectNode parent,
                         Captures captures,
                         Rule.Context context)

Specified by:

apply in interface Rule<ProjectNode>

pushDownProjectOff

protected abstract Optional<PlanNode> pushDownProjectOff(PlanNodeIdAllocator idAllocator,
                                                         N targetNode,
                                                         Set<Symbol> referencedOutputs)