Package io.prestosql.sql.planner.iterative.rule

Class ImplementIntersectAll

java.lang.Object

io.prestosql.sql.planner.iterative.rule.ImplementIntersectAll

All Implemented Interfaces:

Rule<IntersectNode>

public class ImplementIntersectAll
extends Object
implements Rule<IntersectNode>

Implement INTERSECT ALL using union, window and filter.

Transforms:

 - Intersect all
   output: a, b
     - Source1 (a1, b1)
     - Source2 (a2, b2)
     - Source3 (a3, b3)
 

Into:

 - Project (prune helper symbols)
   output: a, b
     - Filter (row_number <= least(least(count1, count2), count3))
         - Window (partition by a, b)
           count1 <- count(marker1)
           count2 <- count(marker2)
           count3 <- count(marker3)
           row_number <- row_number()
               - Union
                 output: a, b, marker1, marker2, marker3
                   - Project (marker1 <- true, marker2 <- null, marker3 <- null)
                       - Source1 (a1, b1)
                   - Project (marker1 <- null, marker2 <- true, marker3 <- null)
                       - Source2 (a2, b2)
                   - Project (marker1 <- null, marker2 <- null, marker3 <- true)
                       - Source3 (a3, b3)
 

Nested Class Summary

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

Rule.Context, Rule.Result

Constructor Summary

Constructors

Constructor	Description
ImplementIntersectAll(Metadata metadata)

Method Summary

Modifier and Type	Method	Description
Rule.Result	apply(IntersectNode node, Captures captures, Rule.Context context)
Pattern<IntersectNode>	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

ImplementIntersectAll

public ImplementIntersectAll(Metadata metadata)

Method Detail

getPattern

public Pattern<IntersectNode> getPattern()

Description copied from interface: Rule

Returns a pattern to which plan nodes this rule applies.

Specified by:

getPattern in interface Rule<IntersectNode>

apply

public Rule.Result apply(IntersectNode node,
                         Captures captures,
                         Rule.Context context)

Specified by:

apply in interface Rule<IntersectNode>