Hi, Our documentation says: "All check constraints and not-null constraints on a parent table are automatically inherited by its children." Okay, this works as expected: test=# create table parent (name text primary key); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "parent_pkey" for table "parent" CREATE TABLE test=*# create table child (age int) inherits (parent) ; CREATE TABLE test=*# \d child Table "public.child" Column | Type | Modifiers --------+---------+----------- name | text | not null age | integer | Inherits: parent Nice, the 'not null' constraint is in the child-table. test=*# rollback; ROLLBACK test=# create table parent (name text); CREATE TABLE test=*# create table child (age int) inherits (parent) ; CREATE TABLE test=*# alter table parent add primary key (name); NOTICE: ALTER TABLE / ADD PRIMARY KEY will create implicit index "parent_pkey" for table "parent" ALTER TABLE test=*# \d child Table "public.child" Column | Type | Modifiers --------+---------+----------- name | text | age | integer | Inherits: parent Doh, there isn't the 'not null' - modifier. The parent-table contains this modifier as part of the primary key - definition. Other test: test=# create table parent (name text); CREATE TABLE test=*# create table child (age int) inherits (parent) ; CREATE TABLE test=*# alter table parent alter column name set not null; ALTER TABLE test=*# \d child Table "public.child" Column | Type | Modifiers --------+---------+----------- name | text | not null age | integer | Inherits: parent Okay, we have again the 'not null'. I think, that's not really clearly. In some case the 'not null' - constraint are in the child-table, in other case they are not. Version 8.4.2. Bug, feature? What have i overlooked? Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG: 0x31720C99, 1006 CCB4 A326 1D42 6431 2EB0 389D 1DC2 3172 0C99 -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general