$this->addColumn('{{%trainer}}', 'studio_id', $this->integer()->notNull());
$this->addForeignKey('fk-trainer-studio', '{{%trainer}}', 'studio_id', '{{%studio}}', 'id', 'CASCADE', 'RESTRICT');
add foreign key fk-trainer-studio: {{%trainer}} (studio_id) references {{%studio}} (id) ...Exception:
SQLSTATE[23000]: Integrity constraint violation: 1452
Cannot add or update a child row: a foreign key constraint fails
(`db`.`#sql-6cb_105`, CONSTRAINT `fk-trainer-studio` FOREIGN KEY (`studio_id`) REFERENCES `studio` (`id`) ON DELETE CASCADE)