SQL & PL/SQL

Hello,

Been scouring the web looking for some help using the REGEXP_LIKE syntax. Haven't found a precise answer, but I think I wrote my own correctly and just wanted to get some validation from other users.


Running Oracle 10.2

Sample Data:

create table test(data varchar2(10));
    insert into test values('01W00012');
    insert into test values('50321070');
    insert into test values('A1391010');
    insert into test values('ZZ260010');
    insert into test values('29374C01');
    insert into test values('A938523A');
    insert into test values('23W48AC3');
    insert into test values('DKFUGHCK');
    insert into test values('09W00032');
    insert into test values('94857283');
    insert into test values('AB-29348');
    insert into test values('98W-8923');
    insert into test values('0AW00005');
    insert into test values('04300W05');
    commit;

What I'm trying to do:
I have a table containing millions of work orders. They are all of length 8. I want to find all work orders where the first 2 characters are a digit only, the third character is a 'W', and the last 5 characters are digits only. Anything else I want to throw away. I think I came up with a working expression... but I'm always hesitant when running it against millions of rows. Here was what I did:

select * from test
    where regexp_like(data, '(^[0-9]{2}W{1}[[:digit:]]{5})');

There are exactly 2 occurrences from up above that match the criteria I'm trying to meet.
Is this expression properly written?

Any help would be greatly appreciated.... reg expressions always make my head spin :(