Question

我在pgAdmin 4中创建了几个表，但由于某种原因我不断将错误称为标题，你能发现原因吗？我没有看到任何问题，我已经查看了类似于我的其他代码示例完全编译。它也可以在IDEone（http://ideone.com/ZBn2Nr）中运行。

谢谢！

Create table item
    (iname varchar(30) primary key,
    itype varchar(30));

Create table Cafe
    (license numeric(5,0) primary key,
    cname varchar(30),
    address varchar(30));

Create table Client
    (cid numeric(5,0) primary key,
    name varchar(30),
    phone numeric(9,0));

Create table Likes
    (cid numeric(5,0),
    iname varchar(30),
    primary key(cid,iname),
    foreign key(cid) references Client,
    foreign key(iname) references item);

Create table Sells
    (license numeric(5,0),
    iname varchar(30),
    price float check(price > 0),
    primary key(license,iname),
    foreign key(license) references Cafe,
    foreign key(iname) references item);

Create table Receipt
    (cid numeric(5,0),
    rno numeric(5,0),
    license numeric(5,0),
    rdate date,
    primary key(cid,rno),
    foreign key(cid) references Client,
    foreign key(license) references Cafe);

Create table Buys
    (cid numeric(5,0),
    rno numeric(5,0),
    iname varchar(30),
    amount int check(amount > 0),
    primary key(cid,rno,iname),
    foreign key(cid) references Client,
    foreign key(rno) references Receipt,
    foreign key(iname) references item);

Answer 1

如果未在references子句中指定列列表，则它将扩展为引用表的主键。

例如：

foreign key(rno) references Receipt

扩展为

foreign key(rno) references Receipt(cid,rno)

因此列数不匹配

在PostgreSql中获取“外键不同意的引用和引用列数”

1 个答案: