Package org.apache.drill.exec.physical.impl.window

Class FrameSupportTemplate

java.lang.Object

org.apache.drill.exec.physical.impl.window.FrameSupportTemplate

All Implemented Interfaces:

WindowFramer

public abstract class FrameSupportTemplate
extends Object
implements WindowFramer

WindowFramer implementation that supports the FRAME clause.
According to the SQL specification, FIRST_VALUE, LAST_VALUE and all aggregate functions support the FRAME clause. This class will handle such functions even if the FRAME clause is not present.

Field Summary

Fields inherited from interface org.apache.drill.exec.physical.impl.window.WindowFramer

FRAME_TEMPLATE_DEFINITION, NOFRAME_TEMPLATE_DEFINITION

Constructor Summary

Constructors

Constructor	Description
FrameSupportTemplate()

Method Summary

Modifier and Type	Method	Description
void	cleanup()
void	doWork()	processes all rows of the first batch.
abstract void	evaluatePeer(int index)	called once for each peer row of the current frame.
int	getOutputCount()
abstract boolean	isPeer(int b1Index, VectorAccessible b1, int b2Index, VectorAccessible b2)	compares two rows from different batches (can be the same), if they have the same value for the order by expression
abstract boolean	isSamePartition(int b1Index, VectorAccessible b1, int b2Index, VectorAccessible b2)	compares two rows from different batches (can be the same), if they have the same value for the partition by expression
abstract void	outputRow(int outIndex)	called once for each row after we evaluate all peer rows.
abstract boolean	resetValues()	reset all window functions
abstract void	saveFirstValue(int index)
void	setup(List<WindowDataBatch> batches, VectorContainer container, OperatorContext oContext, boolean requireFullPartition, WindowPOP popConfig)
abstract void	setupEvaluatePeer(VectorAccessible incoming, VectorAccessible outgoing)
abstract void	setupPartition(WindowDataBatch incoming, VectorAccessible outgoing)	Called once per partition, before processing the partition.
abstract void	setupReadLastValue(VectorAccessible incoming, VectorAccessible outgoing)
abstract void	setupSaveFirstValue(VectorAccessible incoming, VectorAccessible outgoing)
abstract void	setupWriteFirstValue(VectorAccessible incoming, VectorAccessible outgoing)
String	toString()
abstract void	writeLastValue(int index, int outIndex)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

FrameSupportTemplate

public FrameSupportTemplate()

Method Details

setup

public void setup(List<WindowDataBatch> batches,
 VectorContainer container,
 OperatorContext oContext,
 boolean requireFullPartition,
 WindowPOP popConfig)
           throws SchemaChangeException

Specified by:

setup in interface WindowFramer

Throws:

SchemaChangeException

doWork

public void doWork()
            throws SchemaChangeException

processes all rows of the first batch.

Specified by:

doWork in interface WindowFramer

Throws:

SchemaChangeException

getOutputCount

public int getOutputCount()

Specified by:

getOutputCount in interface WindowFramer

Returns:

number rows processed in last batch

cleanup

public void cleanup()

Specified by:

cleanup in interface WindowFramer

toString

public String toString()

Overrides:

toString in class Object

evaluatePeer

public abstract void evaluatePeer(@Named("index")
 int index)

called once for each peer row of the current frame.

Parameters:

index - of row to aggregate

setupEvaluatePeer

public abstract void setupEvaluatePeer(@Named("incoming")
 VectorAccessible incoming,
 @Named("outgoing")
 VectorAccessible outgoing)
                                throws SchemaChangeException

Throws:

SchemaChangeException

setupReadLastValue

public abstract void setupReadLastValue(@Named("incoming")
 VectorAccessible incoming,
 @Named("outgoing")
 VectorAccessible outgoing)
                                 throws SchemaChangeException

Throws:

SchemaChangeException

writeLastValue

public abstract void writeLastValue(@Named("index")
 int index,
 @Named("outIndex")
 int outIndex)

setupSaveFirstValue

public abstract void setupSaveFirstValue(@Named("incoming")
 VectorAccessible incoming,
 @Named("outgoing")
 VectorAccessible outgoing)
                                  throws SchemaChangeException

Throws:

SchemaChangeException

saveFirstValue

public abstract void saveFirstValue(@Named("index")
 int index)

setupWriteFirstValue

public abstract void setupWriteFirstValue(@Named("incoming")
 VectorAccessible incoming,
 @Named("outgoing")
 VectorAccessible outgoing)

outputRow

public abstract void outputRow(@Named("outIndex")
 int outIndex)

called once for each row after we evaluate all peer rows. Used to write a value in the row

Parameters:

outIndex - index of row

setupPartition

public abstract void setupPartition(@Named("incoming")
 WindowDataBatch incoming,
 @Named("outgoing")
 VectorAccessible outgoing)
                             throws SchemaChangeException

Called once per partition, before processing the partition. Used to setup read/write vectors

Parameters:

incoming - batch we will read from

outgoing - batch we will be writing to

Throws:

SchemaChangeException

resetValues

public abstract boolean resetValues()

reset all window functions

isSamePartition

public abstract boolean isSamePartition(@Named("b1Index")
 int b1Index,
 @Named("b1")
 VectorAccessible b1,
 @Named("b2Index")
 int b2Index,
 @Named("b2")
 VectorAccessible b2)

compares two rows from different batches (can be the same), if they have the same value for the partition by expression

Specified by:

isSamePartition in interface WindowFramer

Parameters:

b1Index - index of first row

b1 - batch for first row

b2Index - index of second row

b2 - batch for second row

Returns:

true if the rows are in the same partition

isPeer

public abstract boolean isPeer(@Named("b1Index")
 int b1Index,
 @Named("b1")
 VectorAccessible b1,
 @Named("b2Index")
 int b2Index,
 @Named("b2")
 VectorAccessible b2)

compares two rows from different batches (can be the same), if they have the same value for the order by expression

Specified by:

isPeer in interface WindowFramer

Parameters:

b1Index - index of first row

b1 - batch for first row

b2Index - index of second row

b2 - batch for second row

Returns:

true if the rows are in the same partition