Column definition order

Databases
1

Hello Guys

I am new here, so please go easy on me :shifty:

I am reading the book [ Build Your Own Database Driven Website Using PHP and MySQL 4th Edition ].

I am now on Chapter 2 [ Introducing MySQL ] aaand I have a Question :blush:

Does the order of this matter ?

id INT NOT NULL AUTO_INCREMENT PRIMARY KEY

I mean can this also work ?

id INT PRIMARY KEY AUTO_INCREMENT NOT NULL

I would greatly appreciate any help.

Thank you. :slight_smile:

2

looks like it :slight_smile:

3

Great !

One thing cleared :slight_smile:

4

Ok I think I have found the problem.

I was doing this:

id NOT NULL AUTO_INCREMENT INT PRIMARY KEY

But it seems that at least th Data Type MUST Follow the name of the field … then the order of the others doesn’t matter !! I say that because this worked:

id INT AUTO_INCREMENT PRIMARY KEY NOT NULL

Am I right ?

5

what happened when you tested it? :wink:

6

i don’t think so, because it worked fine when i tested it

CREATE TABLE test_foo
( id INT NOT NULL AUTO_INCREMENT PRIMARY KEY 
, foo VARCHAR(99)
);

CREATE TABLE test_bar
( id INT PRIMARY KEY AUTO_INCREMENT NOT NULL 
, bar VARCHAR(99)
);

you might have something else in your CREATE TABLE statement that we can’t see that’s causing the error

7

OK I have now tested it and I get the following:

Error 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘NOT NULL AUTO_INCREMENT PRIMARY KEY INT, name TEXT, address TEXT) DEFAULT CHARAC’ at line 2

Does that mean It has a specific order that must be followed ? :injured:

8

Hehe I was scared to test it, I thought If I did > it will destroy all the work that I had done up to that point.