申論題

CREATE TABLE Customer
cid INT NOT NULL AUTOINCREMENT,
cnameVARCHAR(10),
balance INT NOT NULL,
margin INT NOT NULL,
PRIMARY KEY (cid);

CREATE TABLE StockTRade
id INT NOT NULL AUTOINCREMENT,
sid INT NOT NULL,
price INT NOT NULL,
share INT NOT NULL,
cid INT NOT NULL,
PRIMARY KEY (id),
FOREIGN KEY (cid) REFERENCES
Customer (cid);