text: create table snail_subfamily (
  	subfamily_id int NOT NULL PRIMARY KEY AUTO_INCREMENT,
  	name varchar(255) NOT NULL,
  	taxonomy_year int NOT NULL
  );
  
  create table snail_subfamily_taxonomer (
  	subfamily_id int NOT NULL,
  	taxonomer_id int NOT NULL,
  	FOREIGN KEY(subfamily_id) REFERENCES snail_subfamily(subfamily_id) ON DELETE CASCADE,
  	FOREIGN KEY(taxonomer_id) REFERENCES snail_taxonomer(taxonomer_id) ON DELETE CASCADE
  );
  