is this wht u want....


create table test(email varchar2(100), domain varchar2(100));

insert into test values('[email protected]', null);
insert into test values('[email protected]', null);
insert into test values('[email protected]', null);

commit;

select * from test;
EMAIL DOMAIN
------------------
[email protected]
[email protected]
[email protected]

update test set domain = substr(email, instr(email, '@') +1 );

3 rows updated.

commit;

select * from test;

EMAIL DOMAIN
---------------------
[email protected] xyz.com
[email protected] bbb.com
[email protected] ccc.com

Cheers!