Yii condition <IS NULL>

How to find row by column with null value?

It doesn't work:

$criteria->condition = '`se开发者_开发百科ller_id` IS NULL';

$criteria->addCondition('seller_id IS NULL');
$data= MODEL::model()->find($criteria);

tried this? **seller_id** is the mapped column name in Yii, it may not be same as the actual column name in your database.