io.prestosql.sql.planner.iterative.rule

Class TransformUncorrelatedInPredicateSubqueryToSemiJoin

java.lang.Object

io.prestosql.sql.planner.iterative.rule.TransformUncorrelatedInPredicateSubqueryToSemiJoin

All Implemented Interfaces:

Rule<ApplyNode>

public class TransformUncorrelatedInPredicateSubqueryToSemiJoin
extends Object
implements Rule<ApplyNode>

This optimizers looks for InPredicate expressions in ApplyNodes and replaces the nodes with SemiJoin nodes.

Plan before optimizer:

 Filter(a IN b):
   Apply
     - correlation: []  // empty
     - input: some plan A producing symbol a
     - subquery: some plan B producing symbol b
 

Plan after optimizer:

 Filter(semijoinresult):
   SemiJoin
     - source: plan A
     - filteringSource: symbol a
     - sourceJoinSymbol: plan B
     - filteringSourceJoinSymbol: symbol b
     - semiJoinOutput: semijoinresult
 

Nested Class Summary

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

Rule.Context, Rule.Result

Constructor Summary

Constructors

Constructor and Description
TransformUncorrelatedInPredicateSubqueryToSemiJoin()

Method Summary

Modifier and Type	Method and Description
Rule.Result	apply(ApplyNode applyNode, Captures captures, Rule.Context context)
Pattern<ApplyNode>	getPattern() Returns a pattern to which plan nodes this rule applies.

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

TransformUncorrelatedInPredicateSubqueryToSemiJoin

public TransformUncorrelatedInPredicateSubqueryToSemiJoin()

Method Detail

getPattern

public Pattern<ApplyNode> getPattern()

Description copied from interface: Rule

Returns a pattern to which plan nodes this rule applies.

Specified by:

getPattern in interface Rule<ApplyNode>

apply

public Rule.Result apply(ApplyNode applyNode,
                         Captures captures,
                         Rule.Context context)

Specified by:

apply in interface Rule<ApplyNode>