SQL 整数类型

Question

我正在尝试创建这个简单的表格：

CREATE TABLE BOOKLENDED
(
LIBRARY_CARD_NUMBER  INTEGER  NOT NULL ,
FOREIGN KEY (LIBRARY_CARD_NUMBER) REFERENCES BORROWER (LIBRARY_CARD_NUMBER),

SEQUENCE INTEGER UNIQUE,

ISBN_NUMBER INT  NOT NULL,
FOREIGN KEY (ISBN_NUMBER) REFERENCES BOOK(ISBN_NUMBER),

LIBRARIAN_ID INTEGER
RETURN_DATE DATE NOT NULL,
CHECKOUT_DATE DATE  NOT NULL
)

我遇到了这个错误：

7：意外标记：语句 [CREATE TABLE BOOKLENDED ( LIBRARY_CARD_NUMBER INTEGER NOT NULL , FOREIGN KEY (LIBRARY_CARD_NUMBER) REFERENCES BORROWER (LIBRARY_CARD_NUMBER)，

序列整数]

Answer 1

您试图一次给出两个约束（NOT NULL,FOREIGN KEY）。相反，您可以在末尾添加FOREIGN KEY：尝试以下操作

CREATE TABLE BOOKLENDED
(
LIBRARY_CARD_NUMBER  INTEGER  NOT NULL ,
SEQUENCE INTEGER,
ISBN_NUMBER INT  NOT NULL,
LIBRARIAN_ID INTEGER,
RETURN_DATE DATE NOT NULL,
CHECKOUT_DATE DATE  NOT NULL,
UNIQUE (SEQUENCE),
FOREIGN KEY (LIBRARY_CARD_NUMBER) REFERENCES BORROWER (LIBRARY_CARD_NUMBER),
FOREIGN KEY (ISBN_NUMBER) REFERENCES BOOK(ISBN_NUMBER)
);