IndexNestedLoopJoinedRowIterator (AxionDB 1.0-M3-dev API)

java.lang.Object
- org.axiondb.engine.rowiterators.BaseRowIterator
- - org.axiondb.engine.rowiterators.AbstractJoinedRowIterator
  - - org.axiondb.engine.rowiterators.IndexNestedLoopJoinedRowIterator

All Implemented Interfaces:

RowIterator
```
public class IndexNestedLoopJoinedRowIterator
extends AbstractJoinedRowIterator
```
The Index Nested Loop Join or Augmented Nested Loop Join (ANL) is by far the most common join method and is the classic Axion join method. An augmented nested loop join is performed by doing a scan over the left subtree and for each row in it, performing an index bracket scan on a portion of the right subtree. The right subtree is read as many times as there are rows in the left subtree. To be a candidate for an ANL join, the subtree pair for a join node must meet the following criteria:
There must be an index(es) defined on the join column(s) for the table in the right subtree.
No other scan on that index has already been set.
When there is an index defined on the left subtree?s table instead of on the right, the optimizer swaps the subtrees to make an ANL join possible. When neither subtree?s table has an index defined on the join column, the optimizer creats a dynamic index on one of the subtree.

Version:: $Revision: 1.3 $ $Date: 2005/04/02 18:23:30 $

Constructor Summary

Constructors
Constructor and Description
`IndexNestedLoopJoinedRowIterator(RowIterator left, int leftJoinColumn, MutableIndexedRowIterator rightIndex, int rightColumnCount, boolean rightOuter, boolean swapLeftAndRight)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type Method and Description

protected RowIterator generateRightRowIterator()

java.lang.String toString()
- Methods inherited from class org.axiondb.engine.rowiterators.AbstractJoinedRowIterator
  current, currentIndex, getJoinCondition, getLeftRowIterator, getRightSideColumnCount, getRowDecorator, hasCurrent, hasNext, hasPrevious, isRightOuter, isSwapLeftAndRight, next, nextIndex, previous, previousIndex, reset, setJoinCondition, setLeftRowIterator, setRightOuter, setRightSideColumnCount, setSwapLeftAndRight
- Methods inherited from class org.axiondb.engine.rowiterators.BaseRowIterator
  add, first, isEmpty, last, next, peekNext, peekPrevious, previous, remove, set, size
- Methods inherited from class java.lang.Object
  clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected RowIterator`	`generateRightRowIterator()`
`java.lang.String`	`toString()`

Constructor Detail

IndexNestedLoopJoinedRowIterator

public IndexNestedLoopJoinedRowIterator(RowIterator left,
                                        int leftJoinColumn,
                                        MutableIndexedRowIterator rightIndex,
                                        int rightColumnCount,
                                        boolean rightOuter,
                                        boolean swapLeftAndRight)
                                 throws AxionException

Throws:: AxionException

Method Detail
- generateRightRowIterator
```
protected RowIterator generateRightRowIterator()
                                        throws AxionException
```
  Specified by:
  
  generateRightRowIterator in class AbstractJoinedRowIterator
  
  Throws:
  
  AxionException
- toString
```
public java.lang.String toString()
```
  Overrides:
  
  toString in class AbstractJoinedRowIterator

Class IndexNestedLoopJoinedRowIterator

Constructor Summary

Method Summary

Methods inherited from class org.axiondb.engine.rowiterators.AbstractJoinedRowIterator

Methods inherited from class org.axiondb.engine.rowiterators.BaseRowIterator

Methods inherited from class java.lang.Object

Constructor Detail

IndexNestedLoopJoinedRowIterator

Method Detail

generateRightRowIterator

toString