yii2的表前缀

在comment中

'components' => [    'db' => [        'class' => 'yii\db\Connection',        'dsn' => 'mysql:host=localhost;dbname=yii',        'username' => 'root',        'password' => 'root',        'charset' => 'utf8',        'tablePrefix'=>'yii_' ],model层中 
public static function tableName(){    return '{{%user}}';}