SQL 服务器外键引用

Question

CREATE TABLE users 
(
    id INTEGER PRIMARY KEY IDENTITY,
    name VARCHAR (128),
    email VARCHAR (128),
    pass VARCHAR (128),
    paid BIT,
    rank FLOAT,
    status INT,
    active BIT
);

CREATE TABLE books 
(
    id INTEGER PRIMARY KEY IDENTITY,
    FOREIGN KEY (owner) REFERENCES users (id),
    FOREIGN KEY (holder) REFERENCES users (id),
    name VARCHAR (128),
    author VARCHAR (128),
    year INTEGER,
    rank FLOAT,
    publisher VARCHAR (128)
);

错误列表：

Msg 1769, Level 16, State 1, Line 18
Foreign key 'owner' references invalid column 'owner' in referencing table 'books'.

Msg 1750, Level 16, State 0, Line 18
Could not create constraint. See previous errors.

Answer 1

您需要定义列来引用它们。您可以像这样将所有定义放在一行中：

CREATE TABLE books (
    id INTEGER PRIMARY KEY IDENTITY,
    owner INTEGER REFERENCES users(id),
    holder INTEGER REFERENCES users(id),
    name VARCHAR(128),
    author VARCHAR(128),
    year INTEGER,
    rank FLOAT,
    publisher VARCHAR (128)
);

Answer 2

您必须声明 var 所有者和持有者
SQL 脚本：

CREATE TABLE books (
id INTEGER PRIMARY KEY IDENTITY,
ownder INTEGER,
holder INTEGER,
name VARCHAR (128),
author VARCHAR (128),
year INTEGER,
rank FLOAT,
publisher VARCHAR (128)
FOREIGN KEY (owner) REFERENCES users (id),
FOREIGN KEY (holder) REFERENCES users (id),
);

Answer 3

CREATE TABLE users (
id INTEGER PRIMARY KEY AUTO_INCREMENT,
name VARCHAR (128),
email VARCHAR (128),
pass VARCHAR (128),
paid BIT,
rank FLOAT,
status INT,
active BIT
);


CREATE TABLE books (
id INTEGER PRIMARY KEY AUTO_INCREMENT,
FOREIGN KEY (owner) REFERENCES users (id),
FOREIGN KEY (holder) REFERENCES users (id),
owner INTEGER,
holder INTEGER,
name VARCHAR (128),
author VARCHAR (128),
year INTEGER,
rank FLOAT,
publisher VARCHAR (128)
);

SQL 服务器外键引用

SQL Server foreign key reference

sql

database

sql-server

reference