Add Condition To Controller Query

I am very sorry for that kind of easy question but i cannot find any matching issue to my simple question.

I am using the following code in my controller and i would like to add a condition like my keyword to search

within the column called ‘url’ … i need a generated query like

select * from redirects where url =’%test%’;

Thanks for your replies.

$keyword = 'test';  


  


$criteria=new CDbCriteria();


$criteria->order = 'url asc';


$count=Redirects::model()->count($criteria);


$pages=new CPagination($count);





// results per page


$pages->pageSize=100;


$pages->applyLimit($criteria);





$models=Redirects::model()->findAll($criteria);





$this->render('listing', array('redirects' => $models,'pages' => $pages ));



$criteria->addSearchCondition('url', $keyword);



CDbCriteria::addSearchCondition().