ReplaceAggregatesWithCRVisitor (Apache Derby V10.14 Internals)

java.lang.Object
- org.apache.derby.impl.sql.compile.ReplaceAggregatesWithCRVisitor

All Implemented Interfaces:: Visitor

class ReplaceAggregatesWithCRVisitor
extends java.lang.Object
implements Visitor

Replace all aggregates with result columns.

Field Summary

Fields
Modifier and Type Field Description

private ResultColumnList rcl

private java.lang.Class<?> skipOverClass

private int tableNumber

Fields
Modifier and Type	Field	Description
`private ResultColumnList`	`rcl`
`private java.lang.Class<?>`	`skipOverClass`
`private int`	`tableNumber`

Constructor Summary

Constructors
Constructor	Description
`ReplaceAggregatesWithCRVisitor(ResultColumnList rcl, int tableNumber)`	Replace all aggregates with column references.
`ReplaceAggregatesWithCRVisitor(ResultColumnList rcl, int tableNumber, java.lang.Class<?> skipOverClass)`
`ReplaceAggregatesWithCRVisitor(ResultColumnList rcl, java.lang.Class<?> nodeToSkip)`	Replace all aggregates with column references.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`skipChildren(Visitable node)`	Don't visit children under the skipOverClass node, if it isn't null.
`boolean`	`stopTraversal()`	Method that is called to see if query tree traversal should be stopped before visiting all nodes.
`Visitable`	`visit(Visitable node)`	Don't do anything unless we have an aggregate node.
`boolean`	`visitChildrenFirst(Visitable node)`	Method that is called to see if `visit()` should be called on the children of `node` before it is called on `node` itself.

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

- Field Detail
  - rcl
```
private ResultColumnList rcl
```
  - skipOverClass
```
private java.lang.Class<?> skipOverClass
```
  - tableNumber
```
private int tableNumber
```
- Constructor Detail
  - ReplaceAggregatesWithCRVisitor
```
ReplaceAggregatesWithCRVisitor(ResultColumnList rcl,
                               int tableNumber)
```
    Replace all aggregates with column references. Add the reference to the RCL. Delegates most work to AggregateNode.replaceAggregatesWithColumnReferences(rcl, tableNumber).
    
    Parameters:
    
    rcl - the result column list
    
    tableNumber - The tableNumber for the new CRs
  - ReplaceAggregatesWithCRVisitor
```
ReplaceAggregatesWithCRVisitor(ResultColumnList rcl,
                               int tableNumber,
                               java.lang.Class<?> skipOverClass)
```
  - ReplaceAggregatesWithCRVisitor
```
ReplaceAggregatesWithCRVisitor(ResultColumnList rcl,
                               java.lang.Class<?> nodeToSkip)
```
    Replace all aggregates with column references. Add the reference to the RCL. Delegates most work to AggregateNode.replaceAggregatesWithColumnReferences(rcl). Doesn't traverse below the passed in class.
    
    Parameters:
    
    rcl - the result column list
    
    nodeToSkip - don't examine anything below nodeToSkip
- Method Detail
  - visit
```
public Visitable visit(Visitable node)
                throws StandardException
```
    Don't do anything unless we have an aggregate node.
    
    Specified by:
    
    visit in interface Visitor
    
    Parameters:
    
    node - the node to process
    
    Returns:
    
    me
    
    Throws:
    
    StandardException - on error
  - skipChildren
```
public boolean skipChildren(Visitable node)
```
    Don't visit children under the skipOverClass node, if it isn't null.
    
    Specified by:
    
    skipChildren in interface Visitor
    
    Parameters:
    
    node - the node to process
    
    Returns:
    
    true/false
  - visitChildrenFirst
```
public boolean visitChildrenFirst(Visitable node)
```
    Description copied from interface: Visitor
    
    Method that is called to see if visit() should be called on the children of node before it is called on node itself. If this method always returns true, the visitor will walk the tree bottom-up. If it always returns false, the tree is visited top-down.
    
    Specified by:
    
    visitChildrenFirst in interface Visitor
    
    Parameters:
    
    node - the top node of a sub-tree about to be visited
    
    Returns:
    
    true if node's children should be visited before node, false otherwise
  - stopTraversal
```
public boolean stopTraversal()
```
    Description copied from interface: Visitor
    
    Method that is called to see if query tree traversal should be stopped before visiting all nodes. Useful for short circuiting traversal if we already know we are done.
    
    Specified by:
    
    stopTraversal in interface Visitor
    
    Returns:
    
    true/false

Class ReplaceAggregatesWithCRVisitor

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

rcl

skipOverClass

tableNumber

Constructor Detail

ReplaceAggregatesWithCRVisitor

ReplaceAggregatesWithCRVisitor

ReplaceAggregatesWithCRVisitor

Method Detail

visit

skipChildren

visitChildrenFirst

stopTraversal