An introductory tutorial on MS SQL foreign KEY constraints and reference constraints

FOREIGN KEY constraints and parameter constraints
The Carifo table of the pubs database creates a foreign key constraint, and the primary key ID of the table is carfactory.
*/
Use Pubs
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/* Do not display the number of lines *
　　 SETNOCOUNT on
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/* Create Sample Table * *
IF EXISTS (SELECT * from dbo.sysobjects
WHERE id = object_id (N ' Carinfo ')
and OBJECTPROPERTY (ID, N ' isusertable ') = 1)
DROPTABLECarinfo
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CREATE TABLE Carinfo (
car_id CHAR (10),
Name CHAR (10),
Type CHAR (20),
Driver_type CHAR (15)
)
IF EXISTS (SELECT * from dbo.sysobjects
WHERE id = object_id (N ' carfactory ')
and OBJECTPROPERTY (ID, N ' isusertable ') = 1)
DROP TABLE Carfactory
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CREATE TABLE Carfactory (
ID CHAR (a) not NULL,
Name CHAR (20),
Postcode CHAR (6),
Telphone CHAR (15),
　　 AddressCHAR (30),
)
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ALTER TABLE Carfactory
ADD CONSTRAINT pk_car_id
PRIMARYKEYNonclustered (ID)
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ALTER TABLE Carinfo
With NOCHECK
ADD CONSTRAINT Car_id_link
FOREIGN KEY (car_id) REFERENCES carfactory (ID)
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Use master
EXEC sp_dboption Pubs, ' dbo use only ', TRUE
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Use Pubs
SET NOCOUNT on
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