不能这么写吗?TABLE transactions 报错建立不成功。可是之前成功过
CREATE TABLE Customers(birth_day DATE, first_name VARCHAR(20), last_name VARCHAR(20), c_id INT,
CONSTRAINT PK_Customers PRIMARY KEY (c_id));
CREATE TABLE Employees(birth_day DATE, first_name VARCHAR(20), last_name VARCHAR(20), e_id INT,
CONSTRAINT PK_Employees PRIMARY KEY (e_id));
CREATE TABLE Transactions(e_id*
INT, c_id*
INT, date DATE, t_id INT,
CONSTRAINT PK_Transactions PRIMARY KEY (t_id),
CONSTRAINT FK_Transactions FOREIGN KEY(e_id*
) REFERENCES Employees(e_id),
CONSTRAINT FK_Transactions FOREIGN KEY(c_id*
) REFERENCES Customers(c_id));
删过库和表,重新弄也没什么效果
您好,题主。参考给你改得sql语句:
CREATE TABLE Transactions(e_id INT, c_id INT, date DATE, t_id INT,
CONSTRAINT PK_Transactions PRIMARY KEY (t_id),
CONSTRAINT FK_Transactions_eid FOREIGN KEY(e_id) REFERENCES Employees(e_id),
CONSTRAINT FK_Transactions_cid FOREIGN KEY(c_id) REFERENCES Customers(c_id));
需要注意的是,字段定义时* 型号可以不要,主要是你定义外键引用的名字是重复了FK_Transactions,e_id 和c_id都用了同一个名字,这样数据库中不允许的。