Change Wordpress URL from example.com/wordpress to example.com/blog -

it seems issue has been talked large number of times, reason, can't seem work.

goal: change wordpress site example.com/wordpress example.com/blog

here i've tried:

1. changed wordpress root folder "wordpress" "blog"
2. then, in phpmyadmin, changed siteurl , home url's example.com/blog

when did not work, went theme's functions.php file , added:

update_option('siteurl','http://example.com/blog'); update_option('home','http://example.com/blog'); 

immediately after opening

<?php 

tag.

is there missing?

you need update urls in database too.

take @ script: http://interconnectit.com/products/search-and-replace-for-wordpress-databases/