mysql - 无法在分配的表中添加外键约束

Question

create table assigned(
        num int,
        tripdate date,
        PRIMARY KEY(num),
        FOREIGN KEY(num) REFERENCES seats(num),
        FOREIGN KEY(tripdate) REFERENCES trip(tripdate)
);

create table trip(
        num int,
        tripdate date,
        meal varchar(50),
        PRIMARY KEY(num,tripdate),
        FOREIGN KEY(num) REFERENCES ticket(num)
);

create table seats(
        aircraft_seats_id varchar(50),
        num int,
        class varchar(50),
        PRIMARY KEY(aircraft_seats_id,num), 
        FOREIGN KEY(aircraft_seats_id) REFERENCES aircraft(crafts_id)
);

创建餐 table 座位( 飞机座位号 varchar(50), 数字整数， 类 varchar(50), 主键(aircraft_seats_id,num), 外键(aircraft_seats_id)引用飞机(crafts_id) )；

分配的表中出现错误，无法添加外键约束

Answer 1

您的陈述中有一个拼写错误。您不能指定与主键和外键相同的名称。注意:外键只是引用另一个表中的主键。