JPA/Hibernate MappingException: Foreign key must have same number

CREATE TABLE IF NOT EXISTS `atutor`.`tests` (
  `test_pk` INT NULL DEFAULT 1,
  `name` VARCHAR(60) NOT NULL,
  `date` DATE NOT NULL,
  `group` VARCHAR(10) NOT NULL,
  `discipline_fk` INT NULL,
  PRIMARY KEY (`name`, `date`, `group`),
  INDEX `fk_test_disciplines_fk_idx` (`discipline_fk` ASC),
  UNIQUE INDEX `test_pk_UNIQUE` (`test_pk` ASC),
  CONSTRAINT `fk_test_disciplines_fk`
    FOREIGN KEY (`discipline_fk`)
    REFERENCES `atutor`.`disciplines` (`discipline_pk`)
    ON DELETE CASCADE
    ON UPDATE NO ACTION)
ENGINE = InnoDB;
 
 
-- -----------------------------------------------------
-- Table `atutor`.`questions`
-- -----------------------------------------------------
DROP TABLE IF EXISTS `atutor`.`questions` ;
 
CREATE TABLE IF NOT EXISTS `atutor`.`questions` (
  `name` VARCHAR(100) NOT NULL,
  `question_pk` INT NULL DEFAULT 1,
  PRIMARY KEY (`name`),
  UNIQUE INDEX `question_pk_UNIQUE` (`question_pk` ASC))
ENGINE = InnoDB;
 
 
-- -----------------------------------------------------
-- Table `atutor`.`test_question`
-- -----------------------------------------------------
DROP TABLE IF EXISTS `atutor`.`test_question` ;
 
CREATE TABLE IF NOT EXISTS `atutor`.`test_question` (
  `test_fk` INT NULL,
  `question_fk` INT NULL,
  INDEX `fk_test_question_question_id_idx` (`question_fk` ASC),
  CONSTRAINT `fk_test_question_question_id`
    FOREIGN KEY (`question_fk`)
    REFERENCES `atutor`.`questions` (`question_pk`)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION,
  CONSTRAINT `fk_test_question_test_id`
    FOREIGN KEY (`test_fk`)
    REFERENCES `atutor`.`tests` (`test_pk`)
    ON DELETE CASCADE
    ON UPDATE NO ACTION)
ENGINE = InnoDB;