Question

drop table reservation;
drop table title_copy;
drop table title;
drop table rental;
drop table member;


create table member(
    member_id number,
    last_name varchar2(25) not null,
    first_name varchar2(25),
    address varchar2(100),
    city varchar2(30),
    phone varchar2(15),
    join_date date DEFAULT SYSDATE not null,
        constraint pk_member primary key(member_id));

commit;

    create table title(
    Title_id number,
    Title varchar2(60) not null,
    Description varchar2(400) not null,
    Rating varchar2(4),
    Category varchar2(20),
    Release_Date date,
        constraint pk_title primary key(Title_id),
        constraint ck_title check(Category = 'Drama''Comedy''Action''Child''Scifi' AND Rating = 'Available''Destroyed''Rented''Reserved'));


commit;

create table title_copy(
    Copy_id number,
    Title_id number,
    Status varchar2(15) not null,
        constraint pk_title_copy primary key(Copy_id,Title_id));


commit;

create table rental(
    Book_Date date,
    Member_id number,
    Copy_id number,
    Act_Ret_Date date,
    Exp_Ret_Date date DEFAULT sysdate+2,
    Title_id number,
        constraint pk_rental primary key(Book_Date,Member_id,Copy_id,Title_id));

commit;


create table reservation(
    Res_Date date,
    Member_id number,
    Title_id number,
        constraint pk_reservation primary key(Res_date,Member_id,Title_id));

commit;     






alter table title_copy  
    add constraint fk_title_copy foreign key(Title_id)
    references title(Title_id);


alter table rental
    add constraint fk_rental2 foreign key(Member_id)
    references member(Member_id);


alter table reservation
    add constraint fk_reservation1 foreign key(Title_id)
    references title(Title_id);


alter table reservation
    add constraint fk_reservation2 foreign key(Member_id)
    references Member(Member_id);


alter table rental
        add constraint fk_rental1 foreign key(Copy_id)
        references title_copy(Copy_id);

alter table rental
        add constraint fk_rental foreign key(Title_id)
        references title_copy(Title_id);





desc member;
desc title;
desc title_copy;
desc rental;
desc reservation;

select constraint_name, constraint_type
from user_constraints
where table_name in ('MEMBER','TITLE','TITLE_COPY','RENTAL','RESERVATION');

我一直收到错误＆＃34;列列表中没有匹配的唯一键或主键＃34;并指的是......

references title_copy(Copy_id);

和

references title_copy(Title_id);

从我试图设置外键约束时起......

alter table rental
        add constraint fk_rental1 foreign key(Copy_id)
        references title_copy(Copy_id);

alter table rental
        add constraint fk_rental foreign key(Title_id)
        references title_copy(Title_id);

Answer 1

检查出来：

https://stackoverflow.com/a/10809656/4633893

如果您的主键是复合键（因为它在标题副本[“主键（Copy_id，Title_id）”]中），那么您不能只有一个外键引用该复合键的一部分（按照评论开始编辑），除非复合键的字段定义为UNIQUE。

Answer 2

你想：

alter table rental
    add constraint fk_rental1 foreign key(Copy_id,Title_id)
    references title_copy(Copy_id,Title_id);

Copy_id和Title_id都不是title_copy的PK。它有一个单一的化合物PK {Copy_id，Title_id}。

（如果这些列中的每一列在title_copy中都是唯一的，则声明它们;然后您可以单独向每个列声明FK。）

获取错误＆＃34;在SQL中没有匹配列列表＆＃34;的唯一键或主键

2 个答案: