com.facebook.presto.spi.function

Interface WindowIndex

public interface WindowIndex

A window index contains the sorted values for a window partition. Each window function argument is available as a separate channel.

Method Summary

Modifier and Type	Method and Description
void	appendTo(int channel, int position, BlockBuilder output) Outputs a value from the index.
boolean	getBoolean(int channel, int position) Gets a value as a boolean.
double	getDouble(int channel, int position) Gets a value as a double.
long	getLong(int channel, int position) Gets a value as a long.
Object	getObject(int channel, int position) Gets an object value.
Block	getSingleValueBlock(int channel, int position) Gets a value stored as a Block.
io.airlift.slice.Slice	getSlice(int channel, int position) Gets a value as a Slice.
boolean	isNull(int channel, int position) Check if a value is null.
int	size() Gets the number of rows in the partition

Method Detail

size

int size()

Gets the number of rows in the partition

isNull

boolean isNull(int channel,
               int position)

Check if a value is null.

Parameters:

channel - argument number

position - row within the partition, starting at zero

Returns:

if the value is null

getBoolean

boolean getBoolean(int channel,
                   int position)

Gets a value as a boolean.

Parameters:

channel - argument number

position - row within the partition, starting at zero

Returns:

value at the specified channel and position

getLong

long getLong(int channel,
             int position)

Gets a value as a long.

Parameters:

channel - argument number

position - row within the partition, starting at zero

Returns:

value at the specified channel and position

getDouble

double getDouble(int channel,
                 int position)

Gets a value as a double.

Parameters:

channel - argument number

position - row within the partition, starting at zero

Returns:

value at the specified channel and position

getSlice

io.airlift.slice.Slice getSlice(int channel,
                                int position)

Gets a value as a Slice.

Parameters:

channel - argument number

position - row within the partition, starting at zero

getSingleValueBlock

Block getSingleValueBlock(int channel,
                          int position)

Gets a value stored as a Block.

Parameters:

channel - argument number

position - row within the partition, starting at zero

getObject

Object getObject(int channel,
                 int position)

Gets an object value.

Parameters:

channel - argument number

position - row within the partition, starting at zero

appendTo

void appendTo(int channel,
              int position,
              BlockBuilder output)

Outputs a value from the index. This is useful for "value" window functions such as lag that operate on arbitrary types without caring about the specific contents.

Parameters:

channel - argument number

position - row within the partition, starting at zero

output - the BlockBuilder to output to