Command::update not adding quotes to values

I’ve this command in a migration

$this->db->createCommand()->update('{{%dispositivo_push}}', ['id_f1' => $myval], ['id_f2' => $var1);

id_f1 and id_f2 are integer fields, and when executing the query it produces this:

UPDATE `cb_dispositivo_push` SET `id_f1`=1 WHERE (`id_f2`=1)

Which generates a weird error in MySQL:
Exception: SQLSTATE[22007]: Invalid datetime format: 1292 Truncated incorrect DOUBLE value: 'comunicazioni'

I found out it solves by adding single quotes around the two 1s, which is a best MySQL pratice IIRC. I was wondering why Yii is not including them. I’m on 2.0.15.1.