SQL Related tables

Related tables

/* This script creates two tables with a composite 
** Primary Key/Foreign Key relationship. It then displays the 
** constraints on each table.
*/

if exists (select * from sysobjects where name='customer' and type='U')
	DROP TABLE customer
GO

if exists (select * from sysobjects where name='orders' and type='U')
	DROP TABLE orders
GO

CREATE TABLE customer
(
cust_id         int            NOT NULL,
location_num    smallint       NULL,
cust_name       varchar(50)    NOT NULL,
CONSTRAINT CUSTOMER_UNQ UNIQUE CLUSTERED (location_num, cust_id)
)

CREATE TABLE orders
(
order_id    int        NOT NULL  IDENTITY CONSTRAINT ORDER_PK
                                 PRIMARY KEY NONCLUSTERED,
cust_num    int        NOT NULL,
cust_loc    smallint   NULL,
CONSTRAINT FK_ORDER_CUSTOMER FOREIGN KEY (cust_loc, cust_num) 
REFERENCES customer (location_num, cust_id)
)

GO

EXEC sp_helpconstraint customer
EXEC sp_helpconstraint orders
GO