尝试使用外键创建表。我不断收到ORA-00904
错误。我究竟做错了什么。是因为尚未创建外键表吗?
CREATE TABLE ingredients(
ingredient_id number(2,0),
ingredient VARCHAR2(55) NOT NULL,
quantity_required VARCHAR2(15) NOT NULL,
optional_ingredient VARCHAR2(30) NOT NULL,
CONSTRAINT pk_ingr_id PRIMARY KEY(ingredient_id),
CONSTRAINT fk_ingredient_list FOREIGN KEY(id) REFERENCES ingredient_list(id)
);