Remove old parameter in URL (PHP)

[Da Fox]

I'm using PHP to create a pagination for a table.I'm using the following code to create the pagination link\[code\]<a class='page-numbers' href='http://stackoverflow.com/questions/3713922/$href&pagenum=$i'>$i</a>\[/code\]With $href\[code\]$href = http://stackoverflow.com/questions/3713922/$_SERVER['REQUEST_URI'];\[/code\]It works well, however, it messes with the address bar, adding each time a new pagenum parameter.So it becomes pagenum=1&pagenum=3&pagenum=4....How to improve that?