FOREIGN KEY after CREATE TABLE?

Started by Peter Harveyover 24 years ago3 messages
#1Peter Harvey
pharvey@codebydesign.com

How can i add foreign keys after the CREATE TABLE? Is there some
combination of other SQL commands that will do the trick?

My problem is;

a. that I have a circular reference between 3 tables
b. that I must be able to reverse engineer the resulting references in
the shema by querying for foreign keys

Right now I am calculating a dependency hierarchy and generating tables
in the resulting order but this does not work for a circular ref.

Aside from the circular ref issues... i think it would be easier and
safer to be able to generate all of the tables in one pass (with primary
key defs) and then add the foreign keys in a second pass.

Any help appreciated.

Peter

#2Christof Glaser
scivi@web.de
In reply to: Peter Harvey (#1)
Re: FOREIGN KEY after CREATE TABLE?

On Sunday, 26. August 2001 00:37, Peter Harvey wrote:

How can i add foreign keys after the CREATE TABLE? Is there some
combination of other SQL commands that will do the trick?

Peter,

try ALTER TABLE a_table ADD CONSTRAINT ... FOREIGN KEY ...

Regards,
--
Christof Glaser

#3Peter Harvey
pharvey@codebydesign.com
In reply to: Peter Harvey (#1)
Re: FOREIGN KEY after CREATE TABLE?

How can i add foreign keys after the CREATE TABLE? Is there some
combination of other SQL commands that will do the trick?

Peter,

try ALTER TABLE a_table ADD CONSTRAINT ... FOREIGN KEY ...

<Grr> I hate asking stupid questions. I scanned the ALTER TABLE syntax
and somehow overlooked it.

Thanks!

Peter