The document creates a customer table with a primary key on the customer ID column. It also creates a cust_status table to store customer status names and IDs. The customer status column is altered to reference the cust_status table through a foreign key. Additional columns for gender, which is constrained to specific values, and registration date, with various default settings, are added to the customer table.

1. use shop
create table customer
(
C_id int identity,
C_name nvarchar(20),
C_status nchar(5)
)
create table cust_status
(
Status_id int,
C_status_name nvarchar(20)
)
use shop
alter table customer
add primary key (C_id)
alter table customer
alter column C_status int
alter table cust_status
add primary key (Status_id)
alter table cust_status
alter column Status_id int not null
ALTER TABLE customer
ADD FOREIGN KEY (C_status)
REFERENCES cust_status(Status_id)
alter table customer
add gender nchar(2) not null
alter table customer
add constraint gender check (gender in ('er', 'em'))
alter table customer
add reg_date datetime not null
alter table customer
drop column reg_date
alter table customer
add reg_date datetime default getdate()
alter table customer
alter column reg_date nchar(10) set default ''