Re: newbie question help!!

Hi,
I think you misread your manuals ... a trigger runs on ONE table, correct ... but it runs PL/SQL and in that you can select from any table you want ... but the one that triggers the trigger.

Triggers can easaly be used as consistency checks ... usually the more advanced. For simple consistency use constraints (like ensuring the parent values exist in the table that's refered).

A just a clear up ... RELATIONAL databases does not mean relationsships between tables. As a matter of fact, the reason that Relational databases became a commercial success is because there is NO pre-defined relationship between tables as opposed other database models. The relationship refered to in RELATIONAL databases is between the fields/tupes/columns in the table. These are related .... SQL allows you to relate data between tables, correct ... but that does not make the tables related. Columns in the tables can occur from the same domain, and thus being related.

• Peter H. Larsen Oracle Consultant

Prashanth Lagisetty wrote:
>
> Hi,
> I have a basic question about triggers!! I've read in the documentation about
> triggers that a only one table can be specified in the triggering statement!!
> So If I want to verify some other table about the validity of the data entered
> can I do that with the help of triggers. (I was wondering about both the
> senarious when the other table is related to the first one and also when there
> is no relation between tables and also this update is done by the corba client
> so I'm looking for something on the server side no front ends). Any help in
> this regard is appreciated.
> Regards,
> --
> Prashanth Lagisetty
> email:lagisett_at_cs.unt.edu

--

Peter H. Larsen, Oracle and Applications specialist Dynamic Resources Inc, Alexandria
Phone: 703-914-9800 #103
Fax: 703-914-9804
Email: plarsen_at_dc.dynares.com
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The above views are my own and does not reflect the views of my employer. Received on Tue Jul 07 1998 - 14:05:20 CDT