Creating(and deleting entries) in another table automatically - mysql

Question

I'm a complete beginner to SQL and I am struggling to find a solution to a pretty simple problem.
The scenario is this: When a user registers on my site they are inserted into a 'users' table with only a few columns(user_id, username, email, password, date).
I don't want to ask anymore of them when they register, however I would like each user to have an optional settings page where they can input additional user info such as forename, surname, bio etc.
To try and keep my database clean I have created a second table called 'user_info' for this info. This table includes the 'user_id' column that exists in 'users'.
What I am struggling with is linking these two tables. I want it so whenever a user is added to the 'users' table a new entry is inserted into 'user_info' with the same 'user_id'. This also needs to work for deletion of users.
So far I have gathered that the use of a FOREIGN KEY is required and have attempted to use CASCADE to solve this.
My tables look like this:
CREATE TABLE users (
user_id INT AUTO_INCREMENT NOT NULL,
username VARCHAR(20) NOT NULL default '',
email VARCHAR(100) NOT NULL default '',
password VARCHAR(100) NOT NULL default '',
create_date DATETIME NOT NULL default '0000-00-00',
PRIMARY KEY (user_id),
UNIQUE KEY (username),
UNIQUE KEY (email)
);
CREATE TABLE user_info (
user_id INT NOT NULL,
forename VARCHAR(30) NOT NULL default '',
surname VARCHAR(30) NOT NULL default '',
dob DATE NOT NULL default '0000-00-00',
location VARCHAR(30) NOT NULL default '',
PRIMARY KEY (user_id),
FOREIGN KEY (user_id) REFERENCES users(user_id) ON DELETE CASCADE ON UPDATE CASCADE
);
I would appreciate any advice in this issue, along with any advice on general best practice!
Kind Regards
Adam

Answer 1

Take a look at Triggers (http://dev.mysql.com/doc/refman/5.0/en/triggers.html).

Answer 2

I am also just a beginner at sql and the solution provided by me might not be the best. You can deal with this problem in two ways
Finding the last inserted id in your users table and then inserting a blank record in the user_info with the fetched id.
Since your User ID is primary key, simply do this everytime when you insert:
SELECT max(USER_ID) FROM users
store the fetched result in a variable and then insert the value of variable in the user_info table
INSERT INTO user_info (user_id) VALUES ('.$theValueInTHeVariable.');
The second method is by using triggers
in this solution you can make a trigger so that whenever a new id is inserted into the users table it automatically fetches the last generated user_id and insert it into the Users_info table.
for more information on triggers refer to the following sits.
link1
link2
If you still face any problem then please post back.