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                * 第一范式:屬性不可分割。 * 第二范式:每個數據表必須擁有主鍵,并且唯一標識整個數據表。 * 第三范式:消除數據冗余,信息只在一個數據表存儲,不能存儲在多張數據表。然后通過外鍵進行關聯。
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