UID generation in oracle - how?

I've 77.4MB of PDF's to search through for this - surely it's been done before!
How does one normally generate a unique ID? Is there a datatype that autoincrements itself?

I thought about using the builtin ROWID, but they're not portable across database installations (eg If I refer to a rowid via a foreign key, and then unload the data, the constraints would be broken when loading the data into a seperate installation, because the rowid's depend on blocksize & offsets etc)

Or maybe the thing to do is to use triggers?

what's the SOP in oracle?
I'm going to go with the following in the meantime:

 create table pk_values
   (
    TABLE_ID number(9) not null primary key,     TABLE_NAME varchar2(32) not null,
    NEXT_UID number(9) not null
   );
insert into pk_values(TABLE_ID,TABLE_NAME,NEXT_UID) select t.table_name, o.object_id, t.num_rows   from all_objects o, all_tables t
 where o.object_type = 'TABLE'
   and o.object_name = t.table_name;

and then

 set transaction read write read committed;  select next_uid from pk_values where table_id=:whatever for update;  update pk_values set next_uid=next_uid+1 where table_id=:whatever;  commit;

comments? suggestions?
john Received on Mon Mar 08 1999 - 00:00:00 CET