The following bug has been logged online:
Bug reference: 3973
Logged by: Alex Hunsaker
Email address: badalex@gmail.com
PostgreSQL version: 8.3.0
Operating system: Linux
Description: pg_dump using inherited tables do not always restore
Details:
create table junk (val integer not null, val2 integer);
create table junk_child () inherits (junk_1);
alter table junk_child alter column val drop not null;
insert into junk_child (val2) values (1);
pg_dump -t junk -t junk_child
pg_restore/psql will fail because junk_child.val now has a not null
constraint