題組內容
二、假設我們有一個投資公司的資料庫包含以下屬性:B-Broker, O-Office of
a broker, I-Investor, S-Stock, Q-Quantity of stock owned by an investor,
D-dividend paid by a stock。整體 schema R =(B, O, I, S, Q, D)。假設此
資料庫有以下 functional dependency, I → B, IS → Q, B → O, S → D。