SQL Join 3 tables

[nichoplast]

Hi all!
I have a problem joining three tables. My tables are:
rooms: room_id ¦ room_name
computers: computer_id ¦ computer_name ¦ room_id
bookings: booking_id ¦ computer_id ¦ date

I want to join them so that i get a listing that displays all room names, and if there is a booking for any computer in that room I also want to display the computer name and the booking date next to the room name. If one room has bookings for several computers I would like to display that room several times.

I have gotten a correct result with:

SELECT rooms.room_name, t.computer_name, temp.date FROM rooms LEFT JOIN (SELECT computers.room_id, computers.computer_name, bookings.date FROM computers JOIN bookings ON (bookings.computer_id = computers.computer_id)) AS temp ON (rooms.room_id = temp.room_id)

but I would like to use something shorter like:
SELECT rooms.room_name, computers.computer_name, bookings.date from computers INNER JOIN bookings ON (computers.computer_id = bookings.computer_id) RIGHT JOIN rooms ON (computers.room_ID = rooms.room_ID)

That however gives me a list where every combination of rooms and computers is listed and bookings displayed when there is a match. I don't really get why this doesn't work and I've been staring at it for days. Could somebody help me out? (I'm using PHP and MySQL)

Thanks,
Nick

 

[Juice05]

Quote: "but I would like to use something shorter like:"

What do you mean by shorter? The query or the resut set?

 

[nichoplast]

I would like the query to be shorter as I'm planning to add other stuff to the query later. Do you have a clue why it doesn't work? I'm stumbled, it seems like there is something on joining in general i don't understand.

 

[PHV]

I'm using PHP and MySQL
Have a look here:

http://www.devshed.com/c/a/MySQL/Understanding-SQL-Joins

Hope This Helps, PH.
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