Specifically, we're going to create a threaded discussion forum. Why do we want a THREADED discussion forum? Well, it's simple: a threaded discussion forum allows a visitor to make multiple replies to the same topic in an ordered fashion. This gives us a discussion tree, with the topic being at the heart of it.

The Code

Our Forum is going to have four main pages:

• Index.php - To let users view a list of all the parent thread (topic) titles.
  
• Viewarticle.php - To let users view a full parent message and replies.
  
• Postre.php - To let users reply to a parent thread.
  
• Post.php - To let users create a new thread (or topic).

We will need some additional files:

• Tutstyle.css - CSS style definitions.
  
• fns_all.php - Contains all the functions used in the forum.
  
• config.php - Contains the database connection settings.

We will also create an "images" folder in the same directory.

Here's the table for our forum:

CREATE TABLE `test` (
  `uid` int(5) unsigned NOT NULL auto_increment,
  `parent` int(5) NOT NULL default '0',
   `name` varchar(90) NOT NULL default '',
  `title` varchar(100) NOT NULL default '',
  `message` text NOT NULL,
  `date` datetime NOT NULL default '0000-00-00 00:00:00',
  PRIMARY KEY  (`uid`)

The field called "uid" is a unique, autonumber field, which will identify each thread in the discussion forum. The field "parent" represents the ID of the parent thread for the current thread (if any), and will be 0 for all new threads. This structure gives us the ability to add as many replies to a thread as we like.

Copy and paste the table structure in your phpAdmin client: