Re: problem with uniques and foreing keys

On Saturday 06 May 2006 01:27 pm, "kernel.alert kernel.alert"
<kernel(dot)alert(at)gmail(dot)com> thus communicated:
--> Hi list...
-->
--> Please i have a problem with this...
-->
--> I create the follow tables...
-->
--> --------------------------------------------------------
-->
--> CREATE TABLE empresa (
--> id_empresa integer NOT NULL primary key,
--> nombre varchar(45),
--> );
--> CREATE TABLE casino (
--> id_casino integer NOT NULL,
--> id_empresa integer REFERENCES empresa(id_empresa),
-->
--> nombre varchar(45),
-->
--> primary key(id_casino,id_empresa)
--> );
--> CREATE TABLE maq_casino (
--> id_empresa integer NOT NULL REFERENCES casino(id_empresa),
--> id_casino integer NOT NULL REFERENCES casino(id_casino),
-->
--> ubicacion_sala varchar(45) default NULL,
--> primary key(id_empresa,id_casino,id_tipo_maquina,id_maq_casino)
--> );
-->
--> --------------------------------------------------------
-->
--> When i'm gonna to create the last table i got this error:
-->
--> ERROR: no hay restriccion unique que coincida con las columnas dadas en
la --> tabla referida <<casino>>
-->
--> That in english is like .. there is no a unique constraint with columns
--> referred in casino table.
-->
-->
--> Please where is the problem...
-->
--> Greetings ...
-->
-->
-->

--
The columns referenced in the maq_casino table must have UNIQUE constraints
on them in their table definition as in:
id_casino integer UNIQUE NOT NULL,
^^^^^^^