运行代码时，我在 Java Derby 数据库中收到此外键错误

Question

运行代码时，我在 Java Derby 数据库中收到此外键错误

CREATE TABLE PURCHASE (
    $PURCHASEID INT NOT NULL GENERATED ALWAYS AS IDENTITY,$
    $PURCHASEDATE DATE,$
    $PURCHASEQUANTITY INT,$
    $CHICPRICE DOUBLE,$
    $CUSTNIC VARCHAR(14) NOT NULL,$
    $PRIMARY KEY (PURCHASEID)$
       $ FOREIGN KEY (CUSTNIC) REFERENCES CUSTOMER(CUSTNIC)$
);

[异常，错误代码 30,000，SQLState 42X01] 语法错误：在第 8 行第 9 列遇到“FOREIGN”。第 8 行第 9 列

Answer 1

如果在主键后加逗号，它应该可以正常工作

CREATE TABLE PURCHASE (
    $PURCHASEID INT NOT NULL GENERATED ALWAYS AS IDENTITY,$
    $PURCHASEDATE DATE,$
    $PURCHASEQUANTITY INT,$
    $CHICPRICE DOUBLE,$
    $CUSTNIC VARCHAR(14) NOT NULL,$
    $PRIMARY KEY (PURCHASEID),$
       $ FOREIGN KEY (CUSTNIC) REFERENCES CUSTOMER(CUSTNIC)$
);

Answer 2

试试这个

CREATE TABLE PURCHASE (
    $PURCHASEID INT NOT NULL GENERATED ALWAYS AS IDENTITY,$
    $PURCHASEDATE DATE,$
    $PURCHASEQUANTITY INT,$
    $CHICPRICE DOUBLE,$
    $CUSTNIC VARCHAR(14) NOT NULL,$
    $PRIMARY KEY (PURCHASEID)$
       $FOREIGN KEY (CUSTNIC) REFERENCES CUSTOMER(CUSTNIC)$
);

Answer 3

尝试创建表，然后添加外键约束

alter table PURCHASE add FOREIGN KEY (CUSTNIC) 
REFERENCES CUSTOMER (CUSTNIC)  

并且在 FOREIGN 之前似乎有一个“，”缺失