Joomla custom link

Ok I have a three tier menu and have SEF l开发者_StackOverflowinks turned on. I have a link like this http://www.site.com/something/column/banning. How would I get it to be like this http://www.site.com/banning, without changing the menus structure

That is not possible by default, as an admin. You will either have to create your own plugin/extension or change the code, or install an extension which allows you to manage and map URIs like sh404SEF. See the SEF category at Joomla Extensions.