The way you do this is in the .htaccess file. The way I would remove my PHP extensions would be like this...

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ $1.php [L,QSA]

Hope that helps, somewhat.

There are many previous threads with this information.

You must first change the link on your page to point to the correct URLs.

Next install a rewrite. While the example posted above would work it is very inefficient because every request hitting your server invokes two very slow disk reads. Remove the two RewriteCond lines and change the ^(.*)$ pattern to ^([^/.]+)$ or similar so it simply tests for "extensionless" requests.

A fatal flaw of the previous code is that a request for the URL

example.com/

is mapped to the file

/.php

The final part of the puzzle is to redirect client .html and .php URL requests to the extensionless URL.

However, for the example in the original post this solution cannot be directly used here because there is no way for mod_rewrite to know to add or remove the "-89" part. You are better off retaining the ID number in the new URLs, otherwise you will have to have a database to look up the URL mappings.

Thanks Guys,

But; is it effect on current ranking & page rank?

You won't lose indexing with a proper 301 . . . .

rewriteRule ^abc-89.html$ /abc [R=301,L]

... but you'd have to do that for every URL, impractical on a large site.

@g1smd: awesome display of restraint. :-)

I tried my best. ;) I'm really trying to sharpen my htaccess skills, so forvive my poor code. This has worked for me on several occasions, I thought it would be okay.

What would you recommend g1smd?

RewriteEngine On
RewriteRule ^([^/.]+)$ $1.php [L,QSA]

Thanks..

I'd rewrite to a PHP script and have all the logic in that PHP script (with data in an array for a small site, or in a database for a large site). The PHP script would send the correct headers back.

The array method was discussed about a month ago, with code included.

Cool, cheers!

But; is it effect on current ranking & page rank

The answer to both of these is yes. Changing the url structure will effect both your ranking and PR. Both will probably come back after Google sorts it all out. A time is a complete guess.