On 5 Dec 2002 at 12:09, Christopher Kings-Lynne wrote: > > > Isn't it identical? The CONSTRAINT <const> is SQL standard optional > clause > > > for all commands that add constraints. > > > > Except that one is ADD CONSTRAINT, the other is an ADD FOREIGN KEY. > > They are similar in nature but different overall. > > I think you're getting a little confused here, Dan. > > http://www3.us.postgresql.org/users-lounge/docs/7.3/postgres/sql-altertable. > html > > There is only one command for adding constraints to a table. It has this > syntax: > > ALTER TABLE [ ONLY ] table [ * ] > ADD table_constraint > > The table_constraint clause is defined like this (basically): > > [CONSTRAINT blah] (PRIMARY KEY or UNIQUE or FOREIGN KEY) ... > > So, the CONSTRAINT blah clause allows you to specify a name for any of the 3 > types of constraint: primary key, unique or foreign key. There's nothing > special about foreign keys in this case. > > If you don't put in the CONSTRAINT blah clause, you get an automatically > assigned constraint name.
Regardless of what is documented, the following is valid and works: ALTER TABLE slave ADD FOREIGN KEY (master_id) REFERENCES master (id) ON DELETE CASCADE; -- Dan Langille : http://www.langille.org/ ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
