FOREIGN KEY !!!!!

We got a little dispute in the FKEY project :-)
   In  section 11.9, the SQL3 draft explicitly discribes what to   do for referential actions ON DELETE  and  ON
UPDATE. First   there seems to be an incompatibility between SQL3 and SQL-92.   While Date describes and Oracle
implementsNO ACTION to raise   an  exception  if  a  PK delete leaves an unsatisfied foreign   key, the SQL3 specs
explicitlydefine that behaviour for  the   RESTRICT action.
 
   Second,  there's absolutely nothing said about anything to do   for NO ACTION in SQL3. Thus,  our  current
implementaion in   fact  doesn't  do  anything meaningful. That makes it totally   legal, to delete a  PK  leaving  an
unsatisfied FK  behind,   resulting  in  an  in  fact  violation.  And NO ACTION is the   default if no referential
actions given  explicitly  in  the   schema.
 
   Don  Baccus  now  suggested, to interpret NO ACTION as "if it   would result in a  violation,  then  silently
rollback this   update  for  the PK row in question".  Not to speak about the   technical problems arising from an
attemptto do so,  but  as   said,  such  a  behaviour  is  nowhere  mentioned in the SQL3   draft.  OTOH it would close
thepossible  violation  hole  in   our implementation of FOREIGN KEY.
 
   What  do others think about it? We need a decision urgent, or   going for the suppress/rollback will cause a
release delay,   definitely.
 


Jan

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