drop table emp cascade;
create table emp (
	code integer primary key,
	depcode integer references dep(code),
	name text not null,
	gender integer check(gender in(1, 2)) -- 1:male, 2:female
);
insert into emp values(564001, 1002, '鈴木義男', 1);
insert into emp values(564002, 1003, '斎藤洋子', 2);
insert into emp values(564003, 1001, '山田美樹', 2);