Re: DB design and foreign keys - Mailing list pgsql-sql

From Jaime Casanova
Subject Re: DB design and foreign keys
Date
Msg-id c2d9e70e0512131032h6591086dwfc73ef57a9c2503b@mail.gmail.com
Whole thread Raw
In response to DB design and foreign keys  (Gianluca Riccardi <ml-reader@moonwatcher.it>)
Responses Re: DB design and foreign keys  (Gianluca Riccardi <ml-reader@moonwatcher.it>)
List pgsql-sql
[...unnecesary...]
> CREATE TABLE orders  (
>   id serial,
>   order_code serial,
>   customer_code integer REFERENCES customers (customer_code) NOT NULL,
>   order_date time without time zone NOT NULL,
>   remote_ip inet NOT NULL,
>   order_time timestamp with time zone NOT NULL,
>   order_type varchar(10) NOT NULL,
>   state varchar(10) NOT NULL,
>   PRIMARY KEY (id, order_code)                           ^^^^^^^^^^^^^^^^^^^
> );
[...unnecesary...]
>
> CREATE TABLE order_items (
>   id serial,
>   order_code integer REFERENCES orders (order_code) NOT NULL,
       ^^^^^^^^^^^^^^ 
[...unnecesary...]
> ERROR:  there is no unique constraint matching given keys for referenced
> table "orders"

this is because the PK in the orders table has two fields not one...
so it founds no unique index on orders(order_code)

--
Atentamente,
Jaime Casanova
(DBA: DataBase Aniquilator ;)


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