Package edu.caltech.nanodb.expressions

Class TupleHasher

java.lang.Object

edu.caltech.nanodb.expressions.TupleHasher

public class TupleHasher
extends Object

Constructor Summary

Constructors

Constructor	Description
TupleHasher()

Method Summary

Modifier and Type	Method	Description
static int	hashTuple(Tuple tuple)
static int	hashTuple(Tuple tuple, List<Integer> colIndexes)	Collects tuple values according to colIndexes into an ArrayList and returns the hash of the list.

Methods inherited from class java.lang.Object

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

Constructor Details

TupleHasher

public TupleHasher()

Method Details

hashTuple

public static int hashTuple(Tuple tuple,
 List<Integer> colIndexes)

Collects tuple values according to colIndexes into an ArrayList and returns the hash of the list. Order matters here, so hash(tuple, [1,2,3]) != hash(tuple, [3,2,1]).

Parameters:

tuple - the tuple to be hashed

colIndexes - the indices of the columns to be hashed.

Returns:

the hash value for the tuple given the passed column indices

hashTuple

public static int hashTuple(Tuple tuple)