Before delete trigger?

Question

We are trying to determine who (like in what applicaton) is deleting rows in one table that leaves "orphaned" rows in another.
We create the following trigger...
create or replace Trigger EFA_TRG_AUDIT
before delete on EFA_EXTERNAL_FILE_ATTACHMENT
for each row
declare
OS_USER varchar2 (20);
HOST varchar2 (20);
MODULE varchar2 (48);
SESSION_USER varchar2 (20);
Begin
if :old.EFA_LDS_UID is not null then
SELECT substr(SYS_CONTEXT ('USERENV', 'SESSION_USER'),1,20) into SESSION_USER from dual;
     SELECT module into MODULE from v$session where audsid=userenv('SESSIONID');
     SELECT substr(SYS_CONTEXT ('USERENV', 'HOST'),1,20) into HOST from dual;
     SELECT substr(SYS_CONTEXT ('USERENV', 'OS_USER'),1,20) into OS_USER from dual;
insert into EFAA_EFA_AUDIT values(
     :old.EFA_UID,
     :old.EFA_SYT_CODE_PARENT,
     :old.EFA_PARENT_KEY,
     :old.EFA_SEQUENCE,
     :old.EFA_FILENAME,
     :old.EFA_DESC,
     :old.EFA_LDS_UID,
     :old.EFA_CREATE_DATE,
     :old.EFA_USR_UID_CREATED_BY,
     :old.EFA_LAST_UPDATE_DATE,
     :old.EFA_USR_UID_UPDATED_BY,
     :old.EFA_FAT_CODE,
     :old.EFA_FILE_SIZE,
     'DELETE',
HOST,
OS_USER,
     MODULE,
User,
     Sysdate);
end if;
end;
This will create an "audit table" which works fine but includes ALL deletes including valid deletes that leave no "orphans" (EFA_LDS_UID).
The LDS table can have rows that are not related to the EFA so a constraint cannot be used.
Any ideas?

Answer 1

no need to clean up the data. just create the FK as NOVALIDATE
from the SQL Reference manual:
ENABLE NOVALIDATE ensures that all new DML operations on the constrained data comply with the constraint. This clause does not ensure that existing data in the table complies with the constraint and therefore does not require a table lock