SQL错误:1364字段'XXXX'没有默认值

So I have, table courses:

我有，餐桌课程:

CREATE  TABLE IF NOT EXISTS `AppDziennik`.`courses` (
  `id_course` INT NOT NULL AUTO_INCREMENT ,
  `name` VARCHAR(80) NOT NULL ,
  `teachers_id_teacher` INT NOT NULL ,
  `end_date` DATE NULL ,
  `about` VARCHAR(255) NULL ,
  `start_date` DATE NULL ,
  PRIMARY KEY (`id_course`) ,
  UNIQUE INDEX `id_course_UNIQUE` (`id_course` ASC) ,
  CONSTRAINT `fk_courses_teachers1`
    FOREIGN KEY (`teachers_id_teacher` )
    REFERENCES `AppDziennik`.`teachers` (`id_teacher` )
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB
CREATE