create table magazine
(Mag_id int primary key,
Name char(30));
create table customer
(cust_id int primary key,
name char(30));
create table bridge
(cust_id int not null,
mag_id int not null,
primary key(mag_id,cust_id));
insert into customer values (10,'John'),(24,'Luke'),(43,'Tony'),(25,'Matt');
insert into magazine values (13,'carMag'),(25,'cosmo'),(9,'farmingMag');
insert into bridge values (10,13),(10,9),(24,13),(42,9),(25,25);
select c.name from magazine m inner join bridge b on (m.mag_id = b.mag_id)
inner join customer c on (c.cust_id = b.cust_id)
where m.Name = 'carmag';
-----Original Message-----
From: mike vogel [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, January 23, 2002 5:51 PM
To: [EMAIL PROTECTED]
Subject: three-way join
i understand that creating a M:N relationship in mysql involves 3
tables, one of which being a bridge, but how do i join the first and
third tables by way of a bridge?
example: a table of subscribers and a table of magazines with a bridge
in the middle. how do i select just the magazines fred is subscribed to?
thanks in advance and sorry if this is a confusing question.
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