You might need to STR() each value before adding them because there could multiple ways to add 2 of those numbers together to get the same sum.

>Try

SELECT Num1 + Num2 FROM mytable ;
>	WHERE Num1 + Num2 IN ;
>		(select Num2+Num1 from mytable ) ;
>UNION ;
>SELECT Num1 + Num2 FROM mytable ;
>	WHERE Num2 + Num1 IN ;
>		(select Num1+Num2 from mytable ) ;
>	INTO CURSOR crsList	
>
>DELETE FROM mytable ;
>	WHERE num1+num2 in ( ;
>		SELECT Num1+Num2 FROM crsList)

>
>> Do I need to input ?nValue each time to delete ? the fact I have thousand
>>mutual records to delete in one single process .