如何根据SQL中的caracters相似度比较字符串？

Question

I'm working on redirecting people if they type a "not really wrong url".

For example I have a good URL http://www.website.com/category/foo-bar-if-bar-foo/. This one works so if a user enter to my website with it, I can retrieve the article corresponding.

But if someone enter to my website with a not really wrong url like http://www.website.com/category/foo-bar-foo/ because an another website has referenced a wrong url, I should redirect him to the right one instead of having a 404 status code...

So how should I do this? and Most important, should I do this ?

I actually use Eloquent with Laravel 4.2.

Thank you in advance.

EDIT

I was wrong about stackoverflow, thanks for your comment. It uses the unique ID of a post.

EDIT 2

I Looked at SOUNDEX function in SQL, it's really good if there is a small difference like a character or two missing. But if my url is as broken as my example, it's not working anymore obviously. But thanks it's gonna be usefull.

Answer 1

Just thinking off the top of my head, you could create a SQL table (with Full-Text indexing enabled) containing all your paths (it might already exist).

In the event that a 404 is triggered, hijack that and do a MATCH (Full Text Search) and return the path with the highest scoring MATCH (you can also consider using a score threshold to prevent nonsensical matches).