The following bug has been logged online: Bug reference: 1514 Logged by: Peter Newman Email address: [EMAIL PROTECTED] PostgreSQL version: 7.4.7 Operating system: Fedora Core 3 Description: Inheritance and Primary Keys Details:
Hi Just exploring the use of inheritance to so some design problems and found some strange behaviour. Not sure if this is a bug or feature? From http://www.postgresql.org/docs/8.0/interactive/tutorial-inheritance.html create table cities (id serial primary key, name varchar(45)); create table capitals (state char(2)) inherits (cities); insert into cities values (1, 'Paris'); insert into cities values (1, 'London'); The second one fails naturally however if you were to insert into capitals values (1, 'Paris', 'FR'); insert into capitals values (1, 'London', 'UK'); This is fine. And if create table capitals (state char(2), primary key (id)) inherits (cities); create table non_capitals (state char(2), primary key (id)) inherits (cities); then insert into capitals values (1, 'Paris', 'FR'); insert into non_capitals values (1, 'London', 'UK'); is also okay. If you were to insert data like this: insert into capitals (name, state) values ('Paris', 'FR'); insert into non_capitals (name, state) values ('London', 'UK'); then the ids in cities would be 1 and 2 using the serial sequencing. This seems inconsistent at least. So my point is (if it is not clear) that the primary key constraint is not enforced through subclass tables. Is this intentional? Cheers, Pete. ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org
