外键连接

Question

所以我有餐桌客户和餐桌预订

我想在脚本中添加一个外键，以便 来自客户的CustID可以在预订中建立一个列并进行连接。

create table customers(
CustID INT NOT NULL,
CustomerName VARCHAR2(25),
CustomerAddress VARCHAR2(50),
CustomerPhone NUMBER(10),
CONSTRAINT pk_cust PRIMARY KEY (CustID) );

和

create table bookings(
BookID INT NOT NULL,
HotelName VARCHAR2(10),
RoomType VARCHAR2(20),
RoomNumber NUMBER(3),
CustID INT,
PRIMARY KEY (BookID),
CONSTRAINT fk_CustBook FOREIGN KEY (CustID)
REFERENCES customers(CustID)
StartDate VARCHAR2(25),
EndDate VARCHAR2(25),
Duration VARCHAR2(25));

误差;

StartDate VARCHAR2(25),
*
ERROR at line 10:
ORA-00907: missing right parenthesis

Answer 1

create table bookings(
BookID INT NOT NULL,
HotelName VARCHAR2(10),
RoomType VARCHAR2(20),
RoomNumber NUMBER(3),
CustID INT,
StartDate VARCHAR2(25),
EndDate VARCHAR2(25),
Duration VARCHAR2(25),
PRIMARY KEY (BookID),
CONSTRAINT fk_CustBook FOREIGN KEY (CustID)
REFERENCES customers(CustID));

完成声明列后，必须声明主键和其他约束。

Answer 2

create table bookings(
BookID INT NOT NULL,
HotelName VARCHAR2(10),
RoomType VARCHAR2(20),
RoomNumber NUMBER(3),
CustID INT,
PRIMARY KEY (BookID),
CONSTRAINT fk_CustBook FOREIGN KEY (CustID)
REFERENCES customers1 (CustID),
StartDate VARCHAR2(25),
EndDate VARCHAR2(25),
Duration VARCHAR2(25));

仔细查看 - 你必须在这个CONSTRAINT fk_CustBook FOREIGN KEY（CustID）之后添加逗号 参考客户1（CustID），