Finding related pages using PHP

[thing3b]

In a MySQL database I have many long text articles.

I am looking for a way to provide the user with a list of related pages when they view any of the articles.

I came up with a few methods, but none seem to suit me. Do people have any other ideas they can throw my way?

The methods I have decided against are:

Manually adding related links to each article

User entry is to slow

Selecting by user entered categories / user entered tags / user entered keywords ( or other user inputed data )

User entry is to slow

Naive bayesian classifier

Designed more for having "running" categories, rather than just finding 1 or 2 related items. I do not want things sorted into predefined categories.

[siMKin]

I don't think there's any automatic way to do this. If you ask a script to find related articles and will just start matching on it's own, it would probably come up with totally unrelated articles that match because of the writing style of the author. Like, for example, if someone, like, uses the word 'like' a lot ;-) this would in the end create a lot of matches with other articles in which the word appears a lot.
If manually tagging the articles with keywords is not an option, maybe you could create one master-record with keywords which you use to match the articles in an automated way. This would prevent unwanted matches on keywords such as 'like'. The only downside is that you would have to create a very good master-record.
Personally i'd just go for manually tagging each article.

[topr8]

Manually adding related links to each article

User entry is to slow

i do this manually, have a table in the db that you use to relate articles to each other or set up some kind of category structure, that way you can dynamically create some kind of related article list