Newbie trying to understand unique/foriegn keys & joins Hi there,
First post to group. I'm just starting out trying to learn mysql to
use alongside php. I'm right at the start and finding it difficult to
grasp the basics of design. I've read about keys and joins but don't
seem to be able to put it into practice.
The question I would like to ask is if you have two tables one with a
unique key of customerid (to be original) and another table with the
customerid as the foreign key how does the second table acquire the
first tables info. Is it automatically added when the foreign key is
created, do you have to add it manually, or is this where the join
comes in?
Sorry its such a basic question but the magic is eluding me.
Many thanks
KC |