On Wed, 28 Apr 2004 21:06:43 +0000, Brian Peasland wrote:
>> In fact, I have a Oracle Type T1 and several type that inherit T1. For
>> each child type, I have an oracle table of that type.
>> My view is a view that return T1 object and is the union of all the table
>> that are childs of t1, so, I'm sure that I have no duplicate row and key
>> (which are uuid so unique in the world) are unique. That's
>> the reason why I thought I could delete a row from that view.
>
> But you can't guarantee uniqueness between the base tables involved in
> the UNION ALL. What mechanism does the database have to guarantee that a
> record in TABLE1 is not also present in TABLE2? There isn't one
> (natively). But all of this makes no difference since you can't delete
> from a UNION ALL view.
>
> Cheers,
> Brian
ID primary key are generated by my java application. It uses Global id
generation like urn:uuid:6ef7f826-2837-457a-bbf1-b963a9c85cd5 which use
MAC address of network card to generate the key. So, i'm sure that I do
not have two similar key in the database.
Fred
Received on Thu Apr 29 2004 - 04:08:41 CDT
