how to store check box value in database for yii2

this is my _form field

<?= $form->field($model, ‘profile’)->inline()->checkBoxList([‘professional’=>‘Professional’,‘jobseeker’=>‘Jobseeker’,‘student’=>‘Student’]); ?>

it show checkboxs correctly.but iam select checkboxs means it shows error the profile must be a string.plz any one help how to solve this problem .And how to store multiple selcted checkbox values in same coloumn for database