org.apache.hadoop.hive.common.ndv.hll

Interface HLLRegister

All Known Implementing Classes:

HLLDenseRegister, HLLSparseRegister

public interface HLLRegister

Method Summary

Modifier and Type	Method and Description
boolean	add(long hashcode) Specify a hashcode to add to hyperloglog register.
void	merge(HLLRegister reg) Merge hyperloglog registers of the same type (SPARSE or DENSE register)
boolean	set(int idx, byte value) Instead of specifying hashcode, this interface can be used to directly specify the register index and register value.

Method Detail

add

boolean add(long hashcode)

Specify a hashcode to add to hyperloglog register.

Parameters:

hashcode - - hashcode to add

Returns:

true if register value is updated else false

set

boolean set(int idx,
            byte value)

Instead of specifying hashcode, this interface can be used to directly specify the register index and register value. This interface is useful when reconstructing hyperloglog from a serialized representation where its not possible to regenerate the hashcode.

Parameters:

idx - - register index

value - - register value

Returns:

true if register value is updated else false

merge

void merge(HLLRegister reg)

Merge hyperloglog registers of the same type (SPARSE or DENSE register)

Parameters:

reg - - register to be merged