create database Market;
use et;
create table customers_info(
c_num int(11) primary key not null unique auto_increment,
c_name varchar(50),
c_contact varchar(50),
c_city varchar(50),
c_birth datetime
);
create table orders(
o_num int(11) primary key not null unique auto_increment,
o_date date,
c_id int(11),
CONSTRAINT customers_fk FOREIGN KEY(c_id)REFERENCES customers_info(c_num)
);
报错:
ERROR 1215 (HY000):cannot add foreign key constraint这个要怎么改?谢谢了
use et;
create table customers_info(
c_num int(11) primary key not null unique auto_increment,
c_name varchar(50),
c_contact varchar(50),
c_city varchar(50),
c_birth datetime
);
create table orders(
o_num int(11) primary key not null unique auto_increment,
o_date date,
c_id int(11),
CONSTRAINT customers_fk FOREIGN KEY(c_id)REFERENCES customers_info(c_num)
);
报错:
ERROR 1215 (HY000):cannot add foreign key constraint这个要怎么改?谢谢了
go
use et;
go
create table customers_info(
c_num int identity(1,1) primary key not null ,
c_name varchar(50),
c_contact varchar(50),
c_city varchar(50),
c_birth datetime
);
create table orders(
o_num int identity(1,1) primary key not null ,
o_date date,
c_id int,
CONSTRAINT customers_fk FOREIGN KEY(c_id)REFERENCES customers_info(c_num)
);