Which query will work fast

Question

Hi,
Can anybody please suggest which query will work fast
distinct role_cd is 1,2,3,4 and null in product table
select * from product
where nvl(role_cd,'4') not in '4'
select * from product
where role_cd in('1','2','3')
I have 13 millions record in this table and there is no index on role_cd

Answer 1

I tried this (11gR2) and get below, but still not sure if it is safe to say that the second one is better:
create table product (role_cd char(2), id number);
begin
dbms_stats.set_table_stats( user, 'PRODUCT', numrows => 13000000 );
end;
explain plan for 
select * from product where nvl(role_cd,'4') not in '4';
Plan hash value: 427209646
| Id  | Operation         | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT  |         |   650K|    10M|   319  (91)| 00:00:04 |
|*  1 |  TABLE ACCESS FULL| PRODUCT |   650K|    10M|   319  (91)| 00:00:04 |
Predicate Information (identified by operation id):
   1 - filter(NVL("ROLE_CD",'4')<>'4')
explain plan for 
select * from product where role_cd in('1','2','3');
Plan hash value: 427209646
| Id  | Operation         | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT  |         |   130K|  2158K|   287  (90)| 00:00:04 |
|*  1 |  TABLE ACCESS FULL| PRODUCT |   130K|  2158K|   287  (90)| 00:00:04 |
Predicate Information (identified by operation id):
   1 - filter("ROLE_CD"='1' OR "ROLE_CD"='2' OR "ROLE_CD"='3')