Is it possible to auto-generate a GUID into an Insert statement?
Also, what type of field should I use to store this GUID?
sys_guid() is a poor option, as other answers have mentioned. One way to generate UUIDs and avoid sequential values is to generate random hex strings yourself:
select regexp_replace(
to_char(
DBMS_RANDOM.value(0, power(2, 128)-1),
'FM0xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'),
'([a-f0-9]{8})([a-f0-9]{4})([a-f0-9]{4})([a-f0-9]{4})([a-f0-9]{12})',
'\1-\2-\3-\4-\5') from DUAL;