Foreign Keys in mySQL

Anon

Hi there,
I am trying to create tables in mysql and I obviously want to create relationships between the different tables...is there a syntax for foreign keys?
eg
would this work???
CREATE TABLE CUSTOMER(
.
.
.
Primary Key (Customer_ID),
Foreign Key (Reservation_ID));

Thanks in advance
Audrey

Anon

There is no foreign key support in MySQL

Anon

So how am I supposed to create relationships??
thanks Mike

Anon

Do it in your head?

Anon

According to the documentation for mySQL, foreign keys are 'NOT' a good thing... Anyhow, it seems the only way around it is to enforce relationships in the program accessing mySQL.

mithril

Actually, foreign key support is planned for one of the 4.0.* releases of MySQL sometime next year. In the past, foreign keys have been considered a "bad thing" because of the impact foreign key constraints place on the speed of UPDATE, INSERT, and DELETE queries. MySQL's developer's therefore decided to trade off the ease of contrainsts for speed, thus forcing app developers to enforce contraints in the SQL code itself (lookup the JOIN syntax in the MySQL manual).

On a side note, I knew a Brad Ford in St. John's, NF a couple years back. Is you he?🙂

-geoff

[deleted]

"According to the documentation for mySQL, foreign keys are 'NOT' a good thing"

That is why MySQL is a piece of crap.
They sacrifice essial functions like foreign keys just to get a bit more speed.

And in the process they completely forget that you still need the foreign key functionality, so you have to do it in your application, which is always slower than doing it in the database. Clever huh? :-)