com.splicemachine.derby.impl.sql.compile

Class CostUtils

java.lang.Object

com.splicemachine.derby.impl.sql.compile.CostUtils

public class CostUtils
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
CostUtils()

Method Summary

Modifier and Type	Method and Description
static long	add(long count1, long count2) In cost calculations we don't want to overflow and a have large positive row count turn into a negative count.

Methods inherited from class java.lang.Object

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

Constructor Detail

CostUtils

public CostUtils()

Method Detail

add

public static long add(long count1,
                       long count2)

In cost calculations we don't want to overflow and a have large positive row count turn into a negative count. This method assumes that for our purposes any count greater than Long.MAX_VALUE can be approximated as Long.MAX_VALUE.We don't have the same consideration for cost as double overflow results in a value of Double.POSITIVE_INFINITY which behaves correctly (to my knowledge) in our cost calculations.