Dear Sir
I am new to MySQL. I've created a table with three keys inside like this:
CREATE TABLE reservation
(
reservation_id INT UNSIGNED NOT NULL AUTO_INCREMENT,
hotel_id INT UNSIGNED NOT NULL,
customer_id INT UNSIGNED NOT NULL,
PRIMARY KEY(reservation_id, hotel_id, customer_id),
............................
and I tried to insert the data by using the following sql statements:
INSERT INTO reservation (reservation_id, hotel_id,
customer_id,business_trip, checkin_month,
checkin_day, checkin_year, checkin_time, checkout_month, checkout_day,
checkout_year,
total_num_guest, room_type, hotel_recommendation, customer_request,
customer_comments) VALUES
(NULL, NULL, NULL, 'yes_business', 'January', '01', '2002', '11:00',
'January', '07', '2002', '3',
'Triple', 'no_recommendations', 'Morning call', 'No')
The book says that I should put NULL in order to let AUTO_INCREMENT generate the id
for me.
However, it kept telling me that hotel_id can't be null (I guess it was because the
hotel_id has been
generated in the "hotel" table by using AUTO_INCREMENT as well). How am I supposed to
connect different primary keys into one table (I mean how can I transfer the hotel_id
in Hotel table to
the Reservation table)? And after that how can I insert those primary keys inside one
table?
Thank you very much for your time.
Sincerely,
Cheri Peng
