SQL & PL/SQL

I'm a pl/sql noob.

I'm messing around with different aspects of pl sql to get my head around it and decided to try to do a transactional delete across a number of tables; if one doesn't work, all roll back. Hit upon an issue.

I have intentionally set up a foreign key exception in my db so that I could see my fk exception was handled. I get an error (included underneath the plsql code) saying I didn't set up a save point. I can't see how, logically, this can be the case.

Is there something I'm doing wrong, or that I'm over looking. Is there an autocomit in oracle/plsql that is mucking this up.

Any help appreciated :o)

for i in 1..firsttab.count
loop
BEGIN
SAVEPOINT onetask;


a:=firsttab(i).a;
b:=firsttab(i).b;
c:=firsttab(i).c;


delete from table1 where t_=b;
delete fromtable2 where pi_=a;
delete from table3 where t_=b;
delete from table4 where pi_=a;
update table5 set pi_=null where id_=b;
update table6 set t_=null where id_=a;
delete from table5 where t_=a;
delete from table6 where pi_=a;
removed:=removed+1;

exception when others then
if sqlcode = -02292 then
dbms.out("don't worry about this line, it has correct syntax in actual code);
end if;
ROLLBACK TO SAVEPOINT onetask;
end;




Error report:
ORA-01086: savepoint 'ONETASK' never established
ORA-02292: integrity constraint (APP.FK_T_PI) violated - child record found
ORA-06512: at "APP.DESTROY_JBPM", line 120
ORA-06512: at line 2
01086. 00000 - "savepoint '%s' never established"
*Cause: Trying to roll back to a save point that was never established.