Re: How to create a database trigger

Your question is not very clear to me. It will help if you include your table structures.

I don't understand why you have a empid in dept table. Why you can't create a forgein key?

Is you really need a trigger, try this:

CREATE or REPLACE TRIGGER Del_Dept
  BEFORE DELETE ON EMP
  FOR EACH ROW
BEGIN
  DELECT
    FROM dept
   WHERE empid = :old.id;
END Del_Dept;

Good luck!
Peter

In article <93f4tl$l40$1_at_nnrp1.deja.com>,   Inna <mednyk_at_my-deja.com> wrote:
>
>
> In article <3A59ABC7.E6D_at_yahoo.com>,
> connor_mcdonald_at_yahoo.com wrote:
> > Inna wrote:
> > >
> > > Hello everyone.
> > > Started creating database triggers and realized that know nothing
 about
> > > it. Please help me in this problem. I have two tables dept and
 emp.
> > > Have primary key ID in emp table and empid in dept, but I can not
 make
> > > it foreign. So I need a trigger <Before delete> on table emp,
 which
> > > going to delete record in dept table. And I don't know how to do
 that,
> > > because my books are not so good, there is no syntax there.
> > > Thank you in advance.
> > > --
> > > Inna.Junior programmer.
> > >
> > > Sent via Deja.com
> > > http://www.deja.com/
> >
> > Check out the ON DELETE CASCADE option when defining a constraint.
> > Since you're new, jump to technet.oracle.com and register (its
 free).
> > Then you can have a wander through the documentation.
> >
> > HTH
> > Connor
> > --
> > ===========================================
> > Connor McDonald
> > http://www.oracledba.co.uk (mirrored at
> > http://www.oradba.freeserve.co.uk)
> >
> >
>
> Thank you. But I know about delete cascade. I can not make empid
> foreign key. That is why I need to know how to create a trigger for
> that.
>
> --
> Inna.Junior programmer.
>
> Sent via Deja.com
> http://www.deja.com/
>

Sent via Deja.com
http://www.deja.com/ Received on Tue Jan 09 2001 - 08:22:52 CST