Re: DDL problems

Foreign key can be concatenated as long as it references concatenated primary key in parent table.

--
Igor Neyman,
Perceptron, Inc.
(734)414-4627
ineyman_at_perceptron.com

Kevin P. Fleming wrote in message
<5awK2.12438$7L.2956_at_news.rdc1.az.home.com>...
>The PRIMARY KEY constraint already incorporates NOT NULL and UNIQUE, so
they
>do not need to exist as explicit constraints.
>
>I am not aware of a way to create a multi-column foreign key.
>
>Gennady wrote in message <36fa8c9e$0$10007_at_fountain.mindlink.net>...
>>Hello,
>>I've got problems:
>>1. When I created a table's primary key this constraint does not
implicitly
>>creates NOT NULL and UNIQUE constraints on the table.
>>2. I can not create a foreign key on composite primary key. The only way
is
>>to split composite key on single field constraints, for example, instead
>of:
>>Constraint FK_LbrGroup_LSizes foreign key(LGroups,LbrGroup) references
>>LumberGroups(LGroups,LbrGroup)
>>
>>I need create:
>>Constraint FK_LGroups_LSizes foreign key(LGroups) references
>>LumberGroups(LGroups),
>>Constraint FK_LbrGroup_LSizes foreign key(LbrGroup) references
>>LumberGroups(LbrGroup)
>>
>>Could you explain me the reasons ?
>>Thank you,
>>Gennady
>>
>>
>>
Received on Thu Mar 25 1999 - 15:57:57 CST