PushPredicateThroughProjectIntoWindow (presto-main 345 API)

java.lang.Object
- io.prestosql.sql.planner.iterative.rule.PushPredicateThroughProjectIntoWindow

All Implemented Interfaces:

Rule<FilterNode>
```
public class PushPredicateThroughProjectIntoWindow
extends Object
implements Rule<FilterNode>
```
This rule pushes filter predicate concerning row number symbol into WindowNode by converting it into TopNRowNumberNode. It skips an identity projection separating FilterNode from WindowNode in the plan tree. TODO This rule should be removed as soon as WindowNode becomes capable of absorbing pruning projections (i.e. capable of pruning outputs).
Transforms:
```
 - Filter (rowNumber <= 5 && a > 1)
     - Project (a, rowNumber)
         - Window (row_number() OVER (ORDER BY a))
             - source (a, b)
 
```
into:
```
 - Filter (a > 1)
     - Project (a, rowNumber)
         - TopNRowNumber (maxRowCountPerPartition = 5, order by a)
             - source (a, b)
 
```

Nested Class Summary
- Nested classes/interfaces inherited from interface io.prestosql.sql.planner.iterative.Rule
  Rule.Context, Rule.Result

Constructor Summary

Constructors
Constructor Description

PushPredicateThroughProjectIntoWindow(Metadata metadata, TypeOperators typeOperators)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Rule.Result`	`apply(FilterNode filter, Captures captures, Rule.Context context)`
`Pattern<FilterNode>`	`getPattern()`	Returns a pattern to which plan nodes this rule applies.
`boolean`	`isEnabled(Session session)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PushPredicateThroughProjectIntoWindow

public PushPredicateThroughProjectIntoWindow(Metadata metadata,
                                             TypeOperators typeOperators)

Method Detail

getPattern
```
public Pattern<FilterNode> getPattern()
```
Description copied from interface: Rule

Returns a pattern to which plan nodes this rule applies.

Specified by:

getPattern in interface Rule<FilterNode>

isEnabled
```
public boolean isEnabled(Session session)
```
Specified by:

isEnabled in interface Rule<FilterNode>

apply

public Rule.Result apply(FilterNode filter,
                         Captures captures,
                         Rule.Context context)

Specified by:: apply in interface Rule<FilterNode>